diff --git a/docker/lib/dependabot/common/file_parser_helper.rb b/docker/lib/dependabot/common/file_parser_helper.rb
new file mode 100644
index 0000000000..454aac9cb3
--- /dev/null
+++ b/docker/lib/dependabot/common/file_parser_helper.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+require "docker_registry2"
+
+require "dependabot/dependency"
+require "dependabot/errors"
+require "dependabot/docker/utils/credentials_finder"
+
+module Dependabot
+  module Docker
+    module FileParserHelper
+      private
+
+      def version_from(parsed_info)
+        return parsed_info.fetch("tag") if parsed_info.fetch("tag")
+
+        version_from_digest(
+          registry: parsed_info.fetch("registry"),
+          image: parsed_info.fetch("image"),
+          digest: parsed_info.fetch("digest")
+        )
+      end
+
+      def source_from(parsed_info)
+        source = {}
+
+        %w(registry tag digest).each do |part|
+          value = parsed_info.fetch(part)
+          source[part.to_sym] = value if value
+        end
+
+        source
+      end
+
+      def version_from_digest(registry:, image:, digest:)
+        return unless digest
+
+        repo = docker_repo_name(image, registry)
+        client = docker_registry_client(registry)
+        client.tags(repo, auto_paginate: true).fetch("tags").find do |tag|
+          digest == client.digest(repo, tag)
+        rescue DockerRegistry2::NotFound
+          # Shouldn't happen, but it does. Example of existing tag with
+          # no manifest is "library/python", "2-windowsservercore".
+          false
+        end
+      rescue DockerRegistry2::RegistryAuthenticationException,
+             RestClient::Forbidden
+        raise if standard_registry?(registry)
+
+        raise PrivateSourceAuthenticationFailure, registry
+      end
+
+      def docker_repo_name(image, registry)
+        return image unless standard_registry?(registry)
+        return image unless image.split("/").count < 2
+
+        "library/#{image}"
+      end
+
+      def docker_registry_client(registry)
+        if registry
+          credentials = registry_credentials(registry)
+
+          DockerRegistry2::Registry.new(
+            "https://#{registry}",
+            user: credentials&.fetch("username", nil),
+            password: credentials&.fetch("password", nil)
+          )
+        else
+          DockerRegistry2::Registry.new("https://registry.hub.docker.com")
+        end
+      end
+
+      def registry_credentials(registry_url)
+        credentials_finder.credentials_for_registry(registry_url)
+      end
+
+      def credentials_finder
+        @credentials_finder ||= Utils::CredentialsFinder.new(credentials)
+      end
+
+      def standard_registry?(registry)
+        return true if registry.nil?
+
+        registry == "registry.hub.docker.com"
+      end
+    end
+  end
+end
diff --git a/docker/lib/dependabot/common/file_updater_helper.rb b/docker/lib/dependabot/common/file_updater_helper.rb
new file mode 100644
index 0000000000..6e4d89a628
--- /dev/null
+++ b/docker/lib/dependabot/common/file_updater_helper.rb
@@ -0,0 +1,92 @@
+# frozen_string_literal: true
+
+require "dependabot/file_updaters"
+require "dependabot/file_updaters/base"
+require "dependabot/errors"
+
+module Dependabot
+  module Docker
+    module FileUpdaterHelper
+      private
+
+      def update_digest_and_tag(file)
+        old_declaration_regex = digest_and_tag_regex(old_digest(file))
+
+        file.content.gsub(old_declaration_regex) do |old_dec|
+          old_dec.
+            gsub("@#{old_digest(file)}", "@#{new_digest(file)}").
+            gsub(":#{dependency.previous_version}",
+                 ":#{dependency.version}")
+        end
+      end
+
+      def update_tag(file)
+        return unless old_tag(file)
+
+        old_declaration =
+          if private_registry_url(file) then "#{private_registry_url(file)}/"
+          else ""
+          end
+        old_declaration += "#{dependency.name}:#{old_tag(file)}"
+
+        old_declaration_regex = tag_regex(old_declaration)
+
+        file.content.gsub(old_declaration_regex) do |old_dec|
+          old_dec.gsub(":#{old_tag(file)}", ":#{new_tag(file)}")
+        end
+      end
+
+      def fetch_file_source(file, reqs)
+        reqs.
+          find { |req| req[:file] == file.name }.
+          fetch(:source)
+      end
+
+      def fetch_property_in_file_source(file, reqs, property)
+        fetch_file_source(file, reqs).fetch(property)
+      end
+
+      def specified_with_digest?(file)
+        fetch_file_source(file, dependency.requirements)[:digest]
+      end
+
+      def new_digest(file)
+        return unless specified_with_digest?(file)
+
+        fetch_property_in_file_source(file, dependency.requirements, :digest)
+      end
+
+      def old_digest(file)
+        return unless specified_with_digest?(file)
+
+        fetch_property_in_file_source(
+          file,
+          dependency.previous_requirements,
+          :digest
+        )
+      end
+
+      def digest(file, reqs)
+        return unless specified_with_digest?(file)
+
+        fetch_property_in_file_source(file, reqs, :digest)
+      end
+
+      def new_tag(file)
+        fetch_property_in_file_source(file, dependency.requirements, :tag)
+      end
+
+      def old_tag(file)
+        fetch_property_in_file_source(
+          file,
+          dependency.previous_requirements,
+          :tag
+        )
+      end
+
+      def private_registry_url(file)
+        fetch_file_source(file, dependency.requirements)[:registry]
+      end
+    end
+  end
+end
diff --git a/docker/lib/dependabot/docker.rb b/docker/lib/dependabot/docker.rb
index 430a0ed51d..5411d80cee 100644
--- a/docker/lib/dependabot/docker.rb
+++ b/docker/lib/dependabot/docker.rb
@@ -10,6 +10,8 @@
 require "dependabot/docker/requirement"
 require "dependabot/docker/version"
 
+require_relative "docker_compose"
+
 require "dependabot/pull_request_creator/labeler"
 Dependabot::PullRequestCreator::Labeler.
   register_label_details("docker", name: "docker", colour: "21ceff")
diff --git a/docker/lib/dependabot/docker/file_parser.rb b/docker/lib/dependabot/docker/file_parser.rb
index 13d3b0b99d..8b6cf7e846 100644
--- a/docker/lib/dependabot/docker/file_parser.rb
+++ b/docker/lib/dependabot/docker/file_parser.rb
@@ -1,18 +1,16 @@
 # frozen_string_literal: true
 
-require "docker_registry2"
-
-require "dependabot/dependency"
 require "dependabot/file_parsers"
 require "dependabot/file_parsers/base"
-require "dependabot/errors"
-require "dependabot/docker/utils/credentials_finder"
+require "dependabot/common/file_parser_helper"
 
 module Dependabot
   module Docker
     class FileParser < Dependabot::FileParsers::Base
       require "dependabot/file_parsers/base/dependency_set"
 
+      include Dependabot::Docker::FileParserHelper
+
       # Details of Docker regular expressions is at
       # https://github.com/docker/distribution/blob/master/reference/regexp.go
       DOMAIN_COMPONENT =
@@ -72,88 +70,6 @@ def dockerfiles
         dependency_files
       end
 
-      def version_from(parsed_from_line)
-        return parsed_from_line.fetch("tag") if parsed_from_line.fetch("tag")
-
-        version_from_digest(
-          registry: parsed_from_line.fetch("registry"),
-          image: parsed_from_line.fetch("image"),
-          digest: parsed_from_line.fetch("digest")
-        )
-      end
-
-      def source_from(parsed_from_line)
-        source = {}
-
-        if parsed_from_line.fetch("registry")
-          source[:registry] = parsed_from_line.fetch("registry")
-        end
-
-        if parsed_from_line.fetch("tag")
-          source[:tag] = parsed_from_line.fetch("tag")
-        end
-
-        if parsed_from_line.fetch("digest")
-          source[:digest] = parsed_from_line.fetch("digest")
-        end
-
-        source
-      end
-
-      def version_from_digest(registry:, image:, digest:)
-        return unless digest
-
-        repo = docker_repo_name(image, registry)
-        client = docker_registry_client(registry)
-        client.tags(repo, auto_paginate: true).fetch("tags").find do |tag|
-          digest == client.digest(repo, tag)
-        rescue DockerRegistry2::NotFound
-          # Shouldn't happen, but it does. Example of existing tag with
-          # no manifest is "library/python", "2-windowsservercore".
-          false
-        end
-      rescue DockerRegistry2::RegistryAuthenticationException,
-             RestClient::Forbidden
-        raise if standard_registry?(registry)
-
-        raise PrivateSourceAuthenticationFailure, registry
-      end
-
-      def docker_repo_name(image, registry)
-        return image unless standard_registry?(registry)
-        return image unless image.split("/").count < 2
-
-        "library/#{image}"
-      end
-
-      def docker_registry_client(registry)
-        if registry
-          credentials = registry_credentials(registry)
-
-          DockerRegistry2::Registry.new(
-            "https://#{registry}",
-            user: credentials&.fetch("username", nil),
-            password: credentials&.fetch("password", nil)
-          )
-        else
-          DockerRegistry2::Registry.new("https://registry.hub.docker.com")
-        end
-      end
-
-      def registry_credentials(registry_url)
-        credentials_finder.credentials_for_registry(registry_url)
-      end
-
-      def credentials_finder
-        @credentials_finder ||= Utils::CredentialsFinder.new(credentials)
-      end
-
-      def standard_registry?(registry)
-        return true if registry.nil?
-
-        registry == "registry.hub.docker.com"
-      end
-
       def check_required_files
         # Just check if there are any files at all.
         return if dependency_files.any?
diff --git a/docker/lib/dependabot/docker/file_updater.rb b/docker/lib/dependabot/docker/file_updater.rb
index 30054001c5..6c5924cae3 100644
--- a/docker/lib/dependabot/docker/file_updater.rb
+++ b/docker/lib/dependabot/docker/file_updater.rb
@@ -3,10 +3,13 @@
 require "dependabot/file_updaters"
 require "dependabot/file_updaters/base"
 require "dependabot/errors"
+require "dependabot/common/file_updater_helper"
 
 module Dependabot
   module Docker
     class FileUpdater < Dependabot::FileUpdaters::Base
+      include Dependabot::Docker::FileUpdaterHelper
+
       FROM_REGEX = /FROM/i.freeze
 
       def self.updated_files_regex
@@ -59,74 +62,14 @@ def updated_dockerfile_content(file)
         updated_content
       end
 
-      def update_digest_and_tag(file)
-        old_declaration_regex = /^#{FROM_REGEX}\s+.*@#{old_digest(file)}/
-
-        file.content.gsub(old_declaration_regex) do |old_dec|
-          old_dec.
-            gsub("@#{old_digest(file)}", "@#{new_digest(file)}").
-            gsub(":#{dependency.previous_version}",
-                 ":#{dependency.version}")
-        end
+      def digest_and_tag_regex(digest)
+        /^#{FROM_REGEX}\s+.*@#{digest}/
       end
 
-      def update_tag(file)
-        return unless old_tag(file)
-
-        old_declaration =
-          if private_registry_url(file) then "#{private_registry_url(file)}/"
-          else ""
-          end
-        old_declaration += "#{dependency.name}:#{old_tag(file)}"
-        escaped_declaration = Regexp.escape(old_declaration)
-
-        old_declaration_regex =
-          %r{^#{FROM_REGEX}\s+(docker\.io/)?#{escaped_declaration}(?=\s|$)}
-
-        file.content.gsub(old_declaration_regex) do |old_dec|
-          old_dec.gsub(":#{old_tag(file)}", ":#{new_tag(file)}")
-        end
-      end
-
-      def specified_with_digest?(file)
-        dependency.
-          requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source)[:digest]
-      end
-
-      def new_digest(file)
-        return unless specified_with_digest?(file)
-
-        dependency.requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source).fetch(:digest)
-      end
-
-      def old_digest(file)
-        return unless specified_with_digest?(file)
-
-        dependency.previous_requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source).fetch(:digest)
-      end
-
-      def new_tag(file)
-        dependency.requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source)[:tag]
-      end
-
-      def old_tag(file)
-        dependency.previous_requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source)[:tag]
-      end
+      def tag_regex(declaration)
+        escaped_declaration = Regexp.escape(declaration)
 
-      def private_registry_url(file)
-        dependency.requirements.
-          find { |r| r[:file] == file.name }.
-          fetch(:source)[:registry]
+        %r{^#{FROM_REGEX}\s+(docker\.io/)?#{escaped_declaration}(?=\s|$)}
       end
     end
   end
diff --git a/docker/lib/dependabot/docker/update_checker.rb b/docker/lib/dependabot/docker/update_checker.rb
index 0358e09d66..e4ca11701b 100644
--- a/docker/lib/dependabot/docker/update_checker.rb
+++ b/docker/lib/dependabot/docker/update_checker.rb
@@ -53,7 +53,7 @@ def updated_requirements
       private
 
       def latest_version_resolvable_with_full_unlock?
-        # Full unlock checks aren't relevant for Dockerfiles
+        # Full unlock checks aren't relevant for Dockerfiles/docker-compose.yml
         false
       end
 
@@ -69,8 +69,8 @@ def version_up_to_date?
         # If the tag isn't up-to-date then we can definitely update
         return false if version_tag_up_to_date? == false
 
-        # Otherwise, if the Dockerfile specifies a digest check that that is
-        # up-to-date
+        # Otherwise, if the Dockerfile/docker-compose.yml specifies 
+        # a digest, check that digest is up to date
         digest_up_to_date?
       end
 
diff --git a/docker/lib/dependabot/docker_compose.rb b/docker/lib/dependabot/docker_compose.rb
new file mode 100644
index 0000000000..75abfae0ba
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+# These all need to be required so the various classes can be registered in a
+# lookup table of package manager names to concrete classes.
+require "dependabot/docker_compose/file_fetcher"
+require "dependabot/docker_compose/file_parser"
+require "dependabot/docker_compose/update_checker"
+require "dependabot/docker_compose/file_updater"
+require "dependabot/docker_compose/metadata_finder"
+require "dependabot/docker_compose/requirement"
+require "dependabot/docker_compose/version"
+
+require "dependabot/pull_request_creator/labeler"
+Dependabot::PullRequestCreator::Labeler.
+  register_label_details("docker_compose", name: "docker", colour: "21ceff")
+
+require "dependabot/dependency"
+Dependabot::Dependency.register_production_check(
+  "docker_compose",
+  ->(_) { true }
+)
diff --git a/docker/lib/dependabot/docker_compose/file_fetcher.rb b/docker/lib/dependabot/docker_compose/file_fetcher.rb
new file mode 100644
index 0000000000..aff6e22838
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/file_fetcher.rb
@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require "dependabot/file_fetchers"
+require "dependabot/file_fetchers/base"
+
+module Dependabot
+  module DockerCompose
+    class FileFetcher < Dependabot::FileFetchers::Base
+      FILENAME_REGEX = /docker-compose(?>\.override)?\.yml/i.freeze
+
+      def self.required_files_in?(filenames)
+        filenames.any? { |f| f.match?(FILENAME_REGEX) }
+      end
+
+      def self.required_files_message
+        "Repo must contain a docker-compose.yaml file."
+      end
+
+      private
+
+      def fetch_files
+        fetched_files = []
+        fetched_files += correctly_encoded_docker_compose_files
+
+        return fetched_files if fetched_files.any?
+
+        if incorrectly_encoded_docker_compose_files.none?
+          raise(
+            Dependabot::DependencyFileNotFound,
+            File.join(directory, "docker-compose.yml")
+          )
+        else
+          raise(
+            Dependabot::DependencyFileNotParseable,
+            incorrectly_encoded_docker_compose_files.first.path
+          )
+        end
+      end
+
+      def docker_compose_files
+        @docker_compose_files ||=
+          repo_contents(raise_errors: false).
+          select { |f| f.type == "file" && f.name.match?(FILENAME_REGEX) }.
+          map { |f| fetch_file_from_host(f.name) }
+      end
+
+      def correctly_encoded_docker_compose_files
+        docker_compose_files.select { |f| f.content.valid_encoding? }
+      end
+
+      def incorrectly_encoded_docker_compose_files
+        docker_compose_files.reject { |f| f.content.valid_encoding? }
+      end
+    end
+  end
+end
+
+Dependabot::FileFetchers.register(
+  "docker_compose",
+  Dependabot::DockerCompose::FileFetcher
+)
diff --git a/docker/lib/dependabot/docker_compose/file_parser.rb b/docker/lib/dependabot/docker_compose/file_parser.rb
new file mode 100644
index 0000000000..8e69630c76
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/file_parser.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+require "yaml"
+
+require "dependabot/file_parsers"
+require "dependabot/file_parsers/base"
+require "dependabot/common/file_parser_helper"
+
+module Dependabot
+  module DockerCompose
+    class FileParser < Dependabot::FileParsers::Base
+      require "dependabot/file_parsers/base/dependency_set"
+
+      include Dependabot::Docker::FileParserHelper
+
+      # Details of Docker regular expressions is at
+      # https://github.com/docker/distribution/blob/master/reference/regexp.go
+      DOMAIN_COMPONENT =
+        /(?:[[:alnum:]]|[[:alnum:]][[[:alnum:]]-]*[[:alnum:]])/.freeze
+      DOMAIN = /(?:#{DOMAIN_COMPONENT}(?:\.#{DOMAIN_COMPONENT})+)/.freeze
+      REGISTRY = /(?<registry>#{DOMAIN}(?::\d+)?)/.freeze
+
+      NAME_COMPONENT = /(?:[a-z\d]+(?:(?:[._]|__|[-]*)[a-z\d]+)*)/.freeze
+      IMAGE = %r{(?<image>#{NAME_COMPONENT}(?:/#{NAME_COMPONENT})*)}.freeze
+
+      TAG = /:(?<tag>[\w][\w.-]{0,127})/.freeze
+      DIGEST = /@(?<digest>[^\s]+)/.freeze
+      NAME = /\s+AS\s+(?<name>[\w-]+)/.freeze
+      FROM_IMAGE =
+        %r{^(#{REGISTRY}/)?#{IMAGE}#{TAG}?#{DIGEST}?#{NAME}?}.freeze
+
+      def parse
+        dependency_set = DependencySet.new
+
+        composefiles.each do |composefile|
+          yaml = YAML.safe_load(composefile.content)
+          yaml["services"].each do |_, service|
+            parsed_from_image =
+              FROM_IMAGE.match(service["image"]).named_captures
+            if parsed_from_image["registry"] == "docker.io"
+              parsed_from_image["registry"] = nil
+            end
+
+            version = version_from(parsed_from_image)
+            next unless version
+
+            dependency_set << Dependency.new(
+              name: parsed_from_image["image"],
+              version: version,
+              package_manager: "docker_compose",
+              requirements: [
+                requirement: nil,
+                groups: [],
+                file: composefile.name,
+                source: source_from(parsed_from_image)
+              ]
+            )
+          end
+        end
+
+        dependency_set.dependencies
+      end
+
+      private
+
+      def composefiles
+        # The DockerCompose file fetcher only fetches docker-compose.yml files,
+        # so no need to filter here
+        dependency_files
+      end
+
+      def check_required_files
+        # Just check if there are any files at all.
+        return if dependency_files.any?
+
+        raise "No docker-compose.yml file!"
+      end
+    end
+  end
+end
+
+Dependabot::FileParsers.register(
+  "docker_compose",
+  Dependabot::DockerCompose::FileParser
+)
diff --git a/docker/lib/dependabot/docker_compose/file_updater.rb b/docker/lib/dependabot/docker_compose/file_updater.rb
new file mode 100644
index 0000000000..a1bde5dcdb
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/file_updater.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+require "dependabot/file_updaters"
+require "dependabot/file_updaters/base"
+require "dependabot/errors"
+require "dependabot/common/file_updater_helper"
+
+module Dependabot
+  module DockerCompose
+    class FileUpdater < Dependabot::FileUpdaters::Base
+      include Dependabot::Docker::FileUpdaterHelper
+
+      IMAGE_REGEX = /image:\s*/.freeze
+
+      def self.updated_files_regex
+        [/docker-compose\.yml/i]
+      end
+
+      def updated_dependency_files
+        updated_files = []
+
+        dependency_files.each do |file|
+          next unless requirement_changed?(file, dependency)
+
+          updated_files <<
+            updated_file(
+              file: file,
+              content: updated_dockercompose_file_content(file)
+            )
+        end
+
+        updated_files.reject! { |f| dependency_files.include?(f) }
+        raise "No files changed!" if updated_files.none?
+
+        updated_files
+      end
+
+      private
+
+      def dependency
+        # docker-compose.yml files will only ever be updating
+        # a single dependency
+        dependencies.first
+      end
+
+      def check_required_files
+        # Just check if there are any files at all.
+        return if dependency_files.any?
+
+        raise "No docker-compose.yml file!"
+      end
+
+      def updated_dockercompose_file_content(file)
+        updated_content =
+          if specified_with_digest?(file)
+            update_digest_and_tag(file)
+          else
+            update_tag(file)
+          end
+
+        raise "Expected content to change!" if updated_content == file.content
+
+        updated_content
+      end
+
+      def digest_and_tag_regex(digest)
+        /^\s*#{IMAGE_REGEX}\s+.*@#{digest}/
+      end
+
+      def tag_regex(declaration)
+        escaped_declaration = Regexp.escape(declaration)
+
+        %r{^\s*#{IMAGE_REGEX}\s+(docker\.io/)?#{escaped_declaration}(?=\s|$)}
+      end
+    end
+  end
+end
+
+Dependabot::FileUpdaters.register(
+  "docker_compose",
+  Dependabot::DockerCompose::FileUpdater
+)
diff --git a/docker/lib/dependabot/docker_compose/metadata_finder.rb b/docker/lib/dependabot/docker_compose/metadata_finder.rb
new file mode 100644
index 0000000000..e551e22ee0
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/metadata_finder.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+require "dependabot/metadata_finders"
+require "dependabot/metadata_finders/base"
+require "dependabot/docker/metadata_finder"
+
+Dependabot::MetadataFinders.
+  register("docker_compose", Dependabot::Docker::MetadataFinder)
diff --git a/docker/lib/dependabot/docker_compose/requirement.rb b/docker/lib/dependabot/docker_compose/requirement.rb
new file mode 100644
index 0000000000..c281cc7338
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/requirement.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require "dependabot/utils"
+require "dependabot/docker/requirement"
+
+Dependabot::Utils.
+  register_requirement_class("docker_compose", Dependabot::Docker::Requirement)
diff --git a/docker/lib/dependabot/docker_compose/update_checker.rb b/docker/lib/dependabot/docker_compose/update_checker.rb
new file mode 100644
index 0000000000..867dd959eb
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/update_checker.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "dependabot/update_checkers"
+require "dependabot/update_checkers/base"
+require "dependabot/docker_compose/version"
+require "dependabot/docker_compose/requirement"
+require "dependabot/docker/update_checker"
+
+module Dependabot
+  module DockerCompose
+    class UpdateChecker < Dependabot::Docker::UpdateChecker
+    end
+  end
+end
+
+Dependabot::UpdateCheckers.register(
+  "docker_compose",
+  Dependabot::DockerCompose::UpdateChecker
+)
diff --git a/docker/lib/dependabot/docker_compose/version.rb b/docker/lib/dependabot/docker_compose/version.rb
new file mode 100644
index 0000000000..b771cfdf10
--- /dev/null
+++ b/docker/lib/dependabot/docker_compose/version.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require "dependabot/utils"
+require "dependabot/docker/version"
+
+Dependabot::Utils.
+  register_version_class("docker_compose", Dependabot::Docker::Version)
diff --git a/docker/spec/dependabot/docker/common/shared_examples_for_docker_update_checkers.rb b/docker/spec/dependabot/docker/common/shared_examples_for_docker_update_checkers.rb
new file mode 100644
index 0000000000..283f804338
--- /dev/null
+++ b/docker/spec/dependabot/docker/common/shared_examples_for_docker_update_checkers.rb
@@ -0,0 +1,652 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/dependency"
+require "dependabot/update_checkers/base"
+require_common_spec "update_checkers/shared_examples_for_update_checkers"
+
+RSpec.shared_examples "a Docker update checker" do
+  it_behaves_like "an update checker"
+
+  let(:checker) do
+    described_class.new(
+      dependency: dependency,
+      dependency_files: [],
+      credentials: credentials,
+      ignored_versions: ignored_versions
+    )
+  end
+  let(:ignored_versions) { [] }
+  let(:credentials) do
+    [{
+      "type" => "git_source",
+      "host" => "github.com",
+      "username" => "x-access-token",
+      "password" => "token"
+    }]
+  end
+
+  let(:dependency) do
+    Dependabot::Dependency.new(
+      name: dependency_name,
+      version: version,
+      requirements: [{
+        requirement: nil,
+        groups: [],
+        file: file_name,
+        source: source
+      }],
+      package_manager: package_manager
+    )
+  end
+  let(:dependency_name) { "ubuntu" }
+  let(:version) { "17.04" }
+  let(:source) { { tag: version } }
+  let(:repo_url) { "https://registry.hub.docker.com/v2/library/ubuntu/" }
+  let(:registry_tags) { fixture("docker", "registry_tags", tags_fixture_name) }
+  let(:tags_fixture_name) { "ubuntu_no_latest.json" }
+
+  before do
+    auth_url = "https://auth.docker.io/token?service=registry.docker.io"
+    stub_request(:get, auth_url).
+      and_return(status: 200, body: { token: "token" }.to_json)
+
+    stub_request(:get, repo_url + "tags/list").
+      and_return(status: 200, body: registry_tags)
+  end
+
+  describe "#can_update?" do
+    subject { checker.can_update?(requirements_to_unlock: :own) }
+
+    context "given an outdated dependency" do
+      let(:version) { "17.04" }
+      it { is_expected.to be_truthy }
+    end
+
+    context "given an up-to-date dependency" do
+      let(:version) { "17.10" }
+      it { is_expected.to be_falsey }
+    end
+
+    context "given a purely numeric version" do
+      let(:version) { "1234567890" }
+      it { is_expected.to be_truthy }
+    end
+
+    context "given a non-numeric version" do
+      let(:version) { "artful" }
+      it { is_expected.to be_falsey }
+
+      context "and a digest" do
+        let(:source) { { digest: "old_digest" } }
+        let(:headers_response) do
+          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+        end
+
+        before do
+          stub_request(:head, repo_url + "manifests/artful").
+            and_return(status: 200, headers: JSON.parse(headers_response))
+        end
+
+        context "that is out-of-date" do
+          let(:source) { { digest: "old_digest" } }
+          it { is_expected.to be_truthy }
+
+          context "but the response doesn't include a new digest" do
+            let(:headers_response) do
+              fixture(
+                "docker",
+                "registry_manifest_headers",
+                "ubuntu_17.10.json"
+              ).gsub(/^\s*"docker_content_digest.*?,/m, "")
+            end
+
+            it { is_expected.to be_falsey }
+          end
+        end
+
+        context "that is up-to-date" do
+          let(:source) do
+            {
+              digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86ca97"\
+                      "eba880ebf600d68608"
+            }
+          end
+
+          it { is_expected.to be_falsey }
+        end
+      end
+    end
+
+    context "when the 'latest' version is just a more precise one" do
+      let(:dependency_name) { "python" }
+      let(:version) { "3.6" }
+      let(:tags_fixture_name) { "python.json" }
+      let(:headers_response) do
+        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+      end
+      let(:repo_url) { "https://registry.hub.docker.com/v2/library/python/" }
+
+      before do
+        stub_request(:get, repo_url + "tags/list").
+          and_return(status: 200, body: registry_tags)
+        stub_request(:head, repo_url + "manifests/3.6").
+          and_return(status: 200, headers: JSON.parse(headers_response))
+        stub_request(:head, repo_url + "manifests/3.6.3").
+          and_return(status: 200, headers: JSON.parse(headers_response))
+      end
+
+      it { is_expected.to be_falsey }
+    end
+  end
+
+  describe "#latest_version" do
+    subject { checker.latest_version }
+
+    it { is_expected.to eq("17.10") }
+
+    context "when the dependency has a non-numeric version" do
+      let(:version) { "artful" }
+      it { is_expected.to eq("artful") }
+
+      context "that starts with a number" do
+        let(:version) { "309403913c7f0848e6616446edec909b55d53571" }
+        it { is_expected.to eq("309403913c7f0848e6616446edec909b55d53571") }
+      end
+    end
+
+    context "when versions at different specificities look equal" do
+      let(:dependency_name) { "ruby" }
+      let(:version) { "2.4.0-slim" }
+      let(:tags_fixture_name) { "ruby_25.json" }
+      before do
+        tags_url = "https://registry.hub.docker.com/v2/library/ruby/tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("2.5.0-slim") }
+    end
+
+    context "when the latest version is being ignored" do
+      let(:ignored_versions) { [">= 17.10"] }
+      it { is_expected.to eq("17.04") }
+    end
+
+    context "when there are also date-like versions" do
+      let(:tags_fixture_name) { "windows-servercore.json" }
+      let(:version) { "10.0.16299.1087" }
+
+      it { is_expected.to eq("10.0.18362.175") }
+
+      context "and we're using one" do
+        let(:version) { "1803" }
+        it { is_expected.to eq("1903") }
+      end
+    end
+
+    context "when there is a latest tag" do
+      let(:tags_fixture_name) { "ubuntu.json" }
+      let(:headers_response) do
+        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+      end
+      let(:version) { "12.10" }
+
+      before do
+        stub_request(:head, repo_url + "manifests/17.10").
+          and_return(
+            status: 200,
+            body: "",
+            headers: JSON.parse(headers_response)
+          )
+
+        # Stub the latest version to return a different digest
+        ["17.04", "latest"].each do |version|
+          stub_request(:head, repo_url + "manifests/#{version}").
+            and_return(
+              status: 200,
+              body: "",
+              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
+            )
+        end
+      end
+
+      it { is_expected.to eq("17.04") }
+    end
+
+    context "when the dependency's version has a prefix" do
+      let(:version) { "artful-20170826" }
+      it { is_expected.to eq("artful-20170916") }
+    end
+
+    context "when the dependency's version starts with a 'v'" do
+      let(:version) { "v1.5.0" }
+      let(:tags_fixture_name) { "kube_state_metrics.json" }
+      it { is_expected.to eq("v1.6.0") }
+    end
+
+    context "when the dependency has SHA suffices that should be ignored" do
+      let(:tags_fixture_name) { "sha_suffices.json" }
+      let(:version) { "7.2-0.1" }
+      it { is_expected.to eq("7.2-0.3.1") }
+
+      context "for an older version of the prefix" do
+        let(:version) { "7.1-0.1" }
+        it { is_expected.to eq("7.1-0.3.1") }
+      end
+    end
+
+    context "when the docker registry times out" do
+      before do
+        stub_request(:get, repo_url + "tags/list").
+          to_raise(RestClient::Exceptions::OpenTimeout).then.
+          to_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("17.10") }
+
+      context "every time" do
+        before do
+          stub_request(:get, repo_url + "tags/list").
+            to_raise(RestClient::Exceptions::OpenTimeout)
+        end
+
+        it "raises" do
+          expect { checker.latest_version }.
+            to raise_error(RestClient::Exceptions::OpenTimeout)
+        end
+
+        context "for a private registry" do
+          let(:dependency_name) { "ubuntu" }
+          let(:dependency) do
+            Dependabot::Dependency.new(
+              name: dependency_name,
+              version: version,
+              requirements: [{
+                requirement: nil,
+                groups: [],
+                file: file_name,
+                source: { registry: "registry-host.io:5000" }
+              }],
+              package_manager: package_manager
+            )
+          end
+          let(:repo_url) { "https://registry-host.io:5000/v2/ubuntu/" }
+          let(:tags_fixture_name) { "ubuntu_no_latest.json" }
+
+          it "raises" do
+            expect { checker.latest_version }.
+              to raise_error(Dependabot::PrivateSourceTimedOut)
+          end
+        end
+      end
+    end
+
+    context "when the dependency's version has a suffix" do
+      let(:dependency_name) { "ruby" }
+      let(:version) { "2.4.0-slim" }
+      let(:tags_fixture_name) { "ruby.json" }
+      before do
+        tags_url = "https://registry.hub.docker.com/v2/library/ruby/tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("2.4.2-slim") }
+    end
+
+    context "when the dependency's version has a prefix and a suffix" do
+      let(:dependency_name) { "adoptopenjdk/openjdk11" }
+      let(:version) { "jdk-11.0.2.7-alpine-slim" }
+      let(:tags_fixture_name) { "openjdk11.json" }
+      let(:repo_url) do
+        "https://registry.hub.docker.com/v2/adoptopenjdk/openjdk11/"
+      end
+      let(:headers_response) do
+        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+      end
+      before do
+        stub_request(:get, repo_url + "tags/list").
+          and_return(status: 200, body: registry_tags)
+
+        stub_request(:head, repo_url + "manifests/#{version}").
+          and_return(
+            status: 200,
+            body: "",
+            headers: JSON.parse(headers_response)
+          )
+
+        # Stub the latest version to return a different digest
+        ["jdk-11.0.2.9", "latest"].each do |version|
+          stub_request(:head, repo_url + "manifests/#{version}").
+            and_return(
+              status: 200,
+              body: "",
+              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
+            )
+        end
+
+        # Stub an oddly-formatted version to come back as a pre-release
+        stub_request(:head, repo_url + "manifests/jdk-11.28").
+          and_return(
+            status: 200,
+            body: "",
+            headers: JSON.parse(headers_response.gsub("3ea1ca1", "11171a2"))
+          )
+      end
+
+      it { is_expected.to eq("jdk-11.0.2.9-alpine-slim") }
+    end
+
+    context "when the dependency has a namespace" do
+      let(:dependency_name) { "moj/ruby" }
+      let(:tags_fixture_name) { "ruby.json" }
+      before do
+        tags_url = "https://registry.hub.docker.com/v2/moj/ruby/tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("2.4.2") }
+
+      context "and dockerhub 401s" do
+        before do
+          tags_url = "https://registry.hub.docker.com/v2/moj/ruby/tags/list"
+          stub_request(:get, tags_url).
+            and_return(
+              status: 401,
+              body: "",
+              headers: { "www_authenticate" => "basic 123" }
+            )
+        end
+
+        it "raises a to PrivateSourceAuthenticationFailure error" do
+          error_class = Dependabot::PrivateSourceAuthenticationFailure
+          expect { checker.latest_version }.
+            to raise_error(error_class) do |error|
+              expect(error.source).to eq("registry.hub.docker.com")
+            end
+        end
+      end
+    end
+
+    context "when the latest version is a pre-release" do
+      let(:dependency_name) { "python" }
+      let(:version) { "3.5" }
+      let(:tags_fixture_name) { "python.json" }
+      before do
+        tags_url = "https://registry.hub.docker.com/v2/library/python/tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("3.6.3") }
+
+      context "and the current version is a pre-release" do
+        let(:version) { "3.7.0a1" }
+        it { is_expected.to eq("3.7.0a2") }
+      end
+    end
+
+    context "when the latest tag points to an older version" do
+      let(:tags_fixture_name) { "dotnet.json" }
+      let(:headers_response) do
+        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+      end
+      let(:version) { "2.0-sdk" }
+      let(:latest_versions) { %w(2-sdk 2.1-sdk 2.1.401-sdk) }
+
+      before do
+        stub_request(:head, repo_url + "manifests/2.2-sdk").
+          and_return(
+            status: 200,
+            body: "",
+            headers: JSON.parse(headers_response)
+          )
+
+        # Stub the latest version to return a different digest
+        [*latest_versions, "latest"].each do |version|
+          stub_request(:head, repo_url + "manifests/#{version}").
+            and_return(
+              status: 200,
+              body: "",
+              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
+            )
+        end
+      end
+
+      it { is_expected.to eq("2.1.401-sdk") }
+
+      context "and a suffix" do
+        let(:version) { "2.0-runtime" }
+        it { is_expected.to eq("2.1.3-runtime") }
+      end
+
+      context "with a paginated response" do
+        let(:pagination_headers) do
+          fixture("docker", "registry_pagination_headers", "next_link.json")
+        end
+        let(:end_pagination_headers) do
+          fixture("docker", "registry_pagination_headers", "no_next_link.json")
+        end
+        before do
+          stub_request(:get, repo_url + "tags/list").
+            and_return(
+              status: 200,
+              body: fixture("docker", "registry_tags", "dotnet_page_1.json"),
+              headers: JSON.parse(pagination_headers)
+            )
+          last = "ukD72mdD/mC8b5xV3susmJzzaTgp3hKwR9nRUW1yZZ6dLc5kfZtKLT2ICo63"\
+                 "WYvt2jq2VyIS3LWB%2Bo9HjGuiYQ6hARJz1jTFdW4jEMKPIg4kRwXypd7HXj"\
+                 "/SnA9iMm3YvNsd4LmPQrO4fpYZgnZZ8rzIIYqex6%2B3A3/mKcTsNKkKDV9V"\
+                 "R3ic6RJjYFCMOEk5/eqsfLaCDYEbtCNoxE2fBDwlzIl/W14f/F%2Bb%2BtQR"\
+                 "Gh3eUKE9nBJpVvAfibAEs215m4ePJm%2BNuVktVjHOYlRG3U03ekr1T7CPD1"\
+                 "Q%2B65wVYi0y2nCIl1/V40nkgG2WX5viYDxUuk3nEdnf55GUocnt38sDZzqB"\
+                 "nyglM9jvbxBzlO8="
+          stub_request(:get, repo_url + "tags/list?last=#{last}").
+            and_return(
+              status: 200,
+              body: fixture("docker", "registry_tags", "dotnet_page_2.json"),
+              headers: JSON.parse(end_pagination_headers)
+            )
+        end
+
+        it { is_expected.to eq("2.1.401-sdk") }
+      end
+
+      context "when the latest tag 404s" do
+        before do
+          stub_request(:head, repo_url + "manifests/latest").
+            to_return(status: 404).then.
+            to_return(
+              status: 200,
+              body: "",
+              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
+            )
+        end
+
+        it { is_expected.to eq("2.1.401-sdk") }
+
+        context "every time" do
+          before do
+            stub_request(:head, repo_url + "manifests/latest").
+              to_return(status: 404)
+          end
+
+          it { is_expected.to eq("2.2-sdk") }
+        end
+      end
+    end
+
+    context "when the dependency's version has a suffix with periods" do
+      let(:dependency_name) { "python" }
+      let(:version) { "3.6.2-alpine3.6" }
+      let(:tags_fixture_name) { "python.json" }
+      before do
+        tags_url = "https://registry.hub.docker.com/v2/library/python/tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      it { is_expected.to eq("3.6.3-alpine3.6") }
+    end
+
+    context "when the dependency has a private registry" do
+      let(:dependency_name) { "ubuntu" }
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: dependency_name,
+          version: version,
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: file_name,
+            source: { registry: "registry-host.io:5000" }
+          }],
+          package_manager: package_manager
+        )
+      end
+      let(:tags_fixture_name) { "ubuntu_no_latest.json" }
+
+      context "without authentication credentials" do
+        before do
+          tags_url = "https://registry-host.io:5000/v2/ubuntu/tags/list"
+          stub_request(:get, tags_url).
+            and_return(
+              status: 401,
+              body: "",
+              headers: { "www_authenticate" => "basic 123" }
+            )
+        end
+
+        it "raises a to PrivateSourceAuthenticationFailure error" do
+          error_class = Dependabot::PrivateSourceAuthenticationFailure
+          expect { checker.latest_version }.
+            to raise_error(error_class) do |error|
+              expect(error.source).to eq("registry-host.io:5000")
+            end
+        end
+      end
+
+      context "with authentication credentials" do
+        let(:credentials) do
+          [{
+            "type" => "git_source",
+            "host" => "github.com",
+            "username" => "x-access-token",
+            "password" => "token"
+          }, {
+            "type" => "docker_registry",
+            "registry" => "registry-host.io:5000",
+            "username" => "grey",
+            "password" => "pa55word"
+          }]
+        end
+
+        before do
+          tags_url = "https://registry-host.io:5000/v2/ubuntu/tags/list"
+          stub_request(:get, tags_url).
+            and_return(status: 200, body: registry_tags)
+        end
+
+        it { is_expected.to eq("17.10") }
+
+        context "that don't have a username or password" do
+          let(:credentials) do
+            [{
+              "type" => "git_source",
+              "host" => "github.com",
+              "username" => "x-access-token",
+              "password" => "token"
+            }, {
+              "type" => "docker_registry",
+              "registry" => "registry-host.io:5000"
+            }]
+          end
+
+          it { is_expected.to eq("17.10") }
+        end
+      end
+    end
+  end
+
+  describe "#latest_resolvable_version" do
+    subject { checker.latest_resolvable_version }
+
+    before { allow(checker).to receive(:latest_version).and_return("delegate") }
+    it { is_expected.to eq("delegate") }
+  end
+
+  describe "#updated_requirements" do
+    subject { checker.updated_requirements }
+
+    context "when specified with a tag" do
+      let(:source) { { tag: version } }
+
+      it "updates the tag" do
+        expect(checker.updated_requirements).
+          to eq(
+            [{
+              requirement: nil,
+              groups: [],
+              file: file_name,
+              source: { tag: "17.10" }
+            }]
+          )
+      end
+    end
+
+    context "when specified with a digest" do
+      let(:source) { { digest: "old_digest" } }
+
+      before do
+        new_headers =
+          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+        stub_request(:head, repo_url + "manifests/17.10").
+          and_return(status: 200, body: "", headers: JSON.parse(new_headers))
+      end
+
+      it "updates the digest" do
+        expect(checker.updated_requirements).
+          to eq(
+            [{
+              requirement: nil,
+              groups: [],
+              file: file_name,
+              source: {
+                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                        "ca97eba880ebf600d68608"
+              }
+            }]
+          )
+      end
+    end
+
+    context "when specified with a digest and a tag" do
+      let(:source) { { digest: "old_digest", tag: "17.04" } }
+
+      before do
+        new_headers =
+          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
+        stub_request(:head, repo_url + "manifests/17.10").
+          and_return(status: 200, body: "", headers: JSON.parse(new_headers))
+      end
+
+      it "updates the tag and the digest" do
+        expect(checker.updated_requirements).
+          to eq(
+            [{
+              requirement: nil,
+              groups: [],
+              file: file_name,
+              source: {
+                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                        "ca97eba880ebf600d68608",
+                tag: "17.10"
+              }
+            }]
+          )
+      end
+    end
+  end
+end
diff --git a/docker/spec/dependabot/docker/file_fetcher_spec.rb b/docker/spec/dependabot/docker/file_fetcher_spec.rb
index 6dfdbddf6e..ff397bc016 100644
--- a/docker/spec/dependabot/docker/file_fetcher_spec.rb
+++ b/docker/spec/dependabot/docker/file_fetcher_spec.rb
@@ -50,7 +50,9 @@
         )
     end
 
-    let(:dockerfile_fixture) { fixture("github", "contents_dockerfile.json") }
+    let(:dockerfile_fixture) do
+      fixture("github", "contents_dockerfile.json")
+    end
 
     it "fetches the Dockerfile" do
       expect(file_fetcher_instance.files.count).to eq(1)
@@ -93,8 +95,12 @@
         )
     end
 
-    let(:dockerfile_fixture) { fixture("github", "contents_dockerfile.json") }
-    let(:dockerfile_2_fixture) { fixture("github", "contents_dockerfile.json") }
+    let(:dockerfile_fixture) do
+      fixture("github", "contents_dockerfile.json")
+    end
+    let(:dockerfile_2_fixture) do
+      fixture("github", "contents_dockerfile.json")
+    end
 
     it "fetches both Dockerfiles" do
       expect(file_fetcher_instance.files.count).to eq(2)
diff --git a/docker/spec/dependabot/docker/update_checker_spec.rb b/docker/spec/dependabot/docker/update_checker_spec.rb
index b813a4ab4f..13fdcc8c6d 100644
--- a/docker/spec/dependabot/docker/update_checker_spec.rb
+++ b/docker/spec/dependabot/docker/update_checker_spec.rb
@@ -1,652 +1,12 @@
 # frozen_string_literal: true
 
 require "spec_helper"
-require "dependabot/dependency"
 require "dependabot/docker/update_checker"
-require_common_spec "update_checkers/shared_examples_for_update_checkers"
+require "dependabot/docker/common/shared_examples_for_docker_update_checkers.rb"
 
 RSpec.describe Dependabot::Docker::UpdateChecker do
-  it_behaves_like "an update checker"
+  it_behaves_like "a Docker update checker"
 
-  let(:checker) do
-    described_class.new(
-      dependency: dependency,
-      dependency_files: [],
-      credentials: credentials,
-      ignored_versions: ignored_versions
-    )
-  end
-  let(:ignored_versions) { [] }
-  let(:credentials) do
-    [{
-      "type" => "git_source",
-      "host" => "github.com",
-      "username" => "x-access-token",
-      "password" => "token"
-    }]
-  end
-
-  let(:dependency) do
-    Dependabot::Dependency.new(
-      name: dependency_name,
-      version: version,
-      requirements: [{
-        requirement: nil,
-        groups: [],
-        file: "Dockerfile",
-        source: source
-      }],
-      package_manager: "docker"
-    )
-  end
-  let(:dependency_name) { "ubuntu" }
-  let(:version) { "17.04" }
-  let(:source) { { tag: version } }
-  let(:repo_url) { "https://registry.hub.docker.com/v2/library/ubuntu/" }
-  let(:registry_tags) { fixture("docker", "registry_tags", tags_fixture_name) }
-  let(:tags_fixture_name) { "ubuntu_no_latest.json" }
-
-  before do
-    auth_url = "https://auth.docker.io/token?service=registry.docker.io"
-    stub_request(:get, auth_url).
-      and_return(status: 200, body: { token: "token" }.to_json)
-
-    stub_request(:get, repo_url + "tags/list").
-      and_return(status: 200, body: registry_tags)
-  end
-
-  describe "#can_update?" do
-    subject { checker.can_update?(requirements_to_unlock: :own) }
-
-    context "given an outdated dependency" do
-      let(:version) { "17.04" }
-      it { is_expected.to be_truthy }
-    end
-
-    context "given an up-to-date dependency" do
-      let(:version) { "17.10" }
-      it { is_expected.to be_falsey }
-    end
-
-    context "given a purely numeric version" do
-      let(:version) { "1234567890" }
-      it { is_expected.to be_truthy }
-    end
-
-    context "given a non-numeric version" do
-      let(:version) { "artful" }
-      it { is_expected.to be_falsey }
-
-      context "and a digest" do
-        let(:source) { { digest: "old_digest" } }
-        let(:headers_response) do
-          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-        end
-
-        before do
-          stub_request(:head, repo_url + "manifests/artful").
-            and_return(status: 200, headers: JSON.parse(headers_response))
-        end
-
-        context "that is out-of-date" do
-          let(:source) { { digest: "old_digest" } }
-          it { is_expected.to be_truthy }
-
-          context "but the response doesn't include a new digest" do
-            let(:headers_response) do
-              fixture(
-                "docker",
-                "registry_manifest_headers",
-                "ubuntu_17.10.json"
-              ).gsub(/^\s*"docker_content_digest.*?,/m, "")
-            end
-
-            it { is_expected.to be_falsey }
-          end
-        end
-
-        context "that is up-to-date" do
-          let(:source) do
-            {
-              digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86ca97"\
-                      "eba880ebf600d68608"
-            }
-          end
-
-          it { is_expected.to be_falsey }
-        end
-      end
-    end
-
-    context "when the 'latest' version is just a more precise one" do
-      let(:dependency_name) { "python" }
-      let(:version) { "3.6" }
-      let(:tags_fixture_name) { "python.json" }
-      let(:headers_response) do
-        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-      end
-      let(:repo_url) { "https://registry.hub.docker.com/v2/library/python/" }
-
-      before do
-        stub_request(:get, repo_url + "tags/list").
-          and_return(status: 200, body: registry_tags)
-        stub_request(:head, repo_url + "manifests/3.6").
-          and_return(status: 200, headers: JSON.parse(headers_response))
-        stub_request(:head, repo_url + "manifests/3.6.3").
-          and_return(status: 200, headers: JSON.parse(headers_response))
-      end
-
-      it { is_expected.to be_falsey }
-    end
-  end
-
-  describe "#latest_version" do
-    subject { checker.latest_version }
-
-    it { is_expected.to eq("17.10") }
-
-    context "when the dependency has a non-numeric version" do
-      let(:version) { "artful" }
-      it { is_expected.to eq("artful") }
-
-      context "that starts with a number" do
-        let(:version) { "309403913c7f0848e6616446edec909b55d53571" }
-        it { is_expected.to eq("309403913c7f0848e6616446edec909b55d53571") }
-      end
-    end
-
-    context "when versions at different specificities look equal" do
-      let(:dependency_name) { "ruby" }
-      let(:version) { "2.4.0-slim" }
-      let(:tags_fixture_name) { "ruby_25.json" }
-      before do
-        tags_url = "https://registry.hub.docker.com/v2/library/ruby/tags/list"
-        stub_request(:get, tags_url).
-          and_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("2.5.0-slim") }
-    end
-
-    context "when the latest version is being ignored" do
-      let(:ignored_versions) { [">= 17.10"] }
-      it { is_expected.to eq("17.04") }
-    end
-
-    context "when there are also date-like versions" do
-      let(:tags_fixture_name) { "windows-servercore.json" }
-      let(:version) { "10.0.16299.1087" }
-
-      it { is_expected.to eq("10.0.18362.175") }
-
-      context "and we're using one" do
-        let(:version) { "1803" }
-        it { is_expected.to eq("1903") }
-      end
-    end
-
-    context "when there is a latest tag" do
-      let(:tags_fixture_name) { "ubuntu.json" }
-      let(:headers_response) do
-        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-      end
-      let(:version) { "12.10" }
-
-      before do
-        stub_request(:head, repo_url + "manifests/17.10").
-          and_return(
-            status: 200,
-            body: "",
-            headers: JSON.parse(headers_response)
-          )
-
-        # Stub the latest version to return a different digest
-        ["17.04", "latest"].each do |version|
-          stub_request(:head, repo_url + "manifests/#{version}").
-            and_return(
-              status: 200,
-              body: "",
-              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
-            )
-        end
-      end
-
-      it { is_expected.to eq("17.04") }
-    end
-
-    context "when the dependency's version has a prefix" do
-      let(:version) { "artful-20170826" }
-      it { is_expected.to eq("artful-20170916") }
-    end
-
-    context "when the dependency's version starts with a 'v'" do
-      let(:version) { "v1.5.0" }
-      let(:tags_fixture_name) { "kube_state_metrics.json" }
-      it { is_expected.to eq("v1.6.0") }
-    end
-
-    context "when the dependency has SHA suffices that should be ignored" do
-      let(:tags_fixture_name) { "sha_suffices.json" }
-      let(:version) { "7.2-0.1" }
-      it { is_expected.to eq("7.2-0.3.1") }
-
-      context "for an older version of the prefix" do
-        let(:version) { "7.1-0.1" }
-        it { is_expected.to eq("7.1-0.3.1") }
-      end
-    end
-
-    context "when the docker registry times out" do
-      before do
-        stub_request(:get, repo_url + "tags/list").
-          to_raise(RestClient::Exceptions::OpenTimeout).then.
-          to_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("17.10") }
-
-      context "every time" do
-        before do
-          stub_request(:get, repo_url + "tags/list").
-            to_raise(RestClient::Exceptions::OpenTimeout)
-        end
-
-        it "raises" do
-          expect { checker.latest_version }.
-            to raise_error(RestClient::Exceptions::OpenTimeout)
-        end
-
-        context "for a private registry" do
-          let(:dependency_name) { "ubuntu" }
-          let(:dependency) do
-            Dependabot::Dependency.new(
-              name: dependency_name,
-              version: version,
-              requirements: [{
-                requirement: nil,
-                groups: [],
-                file: "Dockerfile",
-                source: { registry: "registry-host.io:5000" }
-              }],
-              package_manager: "docker"
-            )
-          end
-          let(:repo_url) { "https://registry-host.io:5000/v2/ubuntu/" }
-          let(:tags_fixture_name) { "ubuntu_no_latest.json" }
-
-          it "raises" do
-            expect { checker.latest_version }.
-              to raise_error(Dependabot::PrivateSourceTimedOut)
-          end
-        end
-      end
-    end
-
-    context "when the dependency's version has a suffix" do
-      let(:dependency_name) { "ruby" }
-      let(:version) { "2.4.0-slim" }
-      let(:tags_fixture_name) { "ruby.json" }
-      before do
-        tags_url = "https://registry.hub.docker.com/v2/library/ruby/tags/list"
-        stub_request(:get, tags_url).
-          and_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("2.4.2-slim") }
-    end
-
-    context "when the dependency's version has a prefix and a suffix" do
-      let(:dependency_name) { "adoptopenjdk/openjdk11" }
-      let(:version) { "jdk-11.0.2.7-alpine-slim" }
-      let(:tags_fixture_name) { "openjdk11.json" }
-      let(:repo_url) do
-        "https://registry.hub.docker.com/v2/adoptopenjdk/openjdk11/"
-      end
-      let(:headers_response) do
-        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-      end
-      before do
-        stub_request(:get, repo_url + "tags/list").
-          and_return(status: 200, body: registry_tags)
-
-        stub_request(:head, repo_url + "manifests/#{version}").
-          and_return(
-            status: 200,
-            body: "",
-            headers: JSON.parse(headers_response)
-          )
-
-        # Stub the latest version to return a different digest
-        ["jdk-11.0.2.9", "latest"].each do |version|
-          stub_request(:head, repo_url + "manifests/#{version}").
-            and_return(
-              status: 200,
-              body: "",
-              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
-            )
-        end
-
-        # Stub an oddly-formatted version to come back as a pre-release
-        stub_request(:head, repo_url + "manifests/jdk-11.28").
-          and_return(
-            status: 200,
-            body: "",
-            headers: JSON.parse(headers_response.gsub("3ea1ca1", "11171a2"))
-          )
-      end
-
-      it { is_expected.to eq("jdk-11.0.2.9-alpine-slim") }
-    end
-
-    context "when the dependency has a namespace" do
-      let(:dependency_name) { "moj/ruby" }
-      let(:tags_fixture_name) { "ruby.json" }
-      before do
-        tags_url = "https://registry.hub.docker.com/v2/moj/ruby/tags/list"
-        stub_request(:get, tags_url).
-          and_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("2.4.2") }
-
-      context "and dockerhub 401s" do
-        before do
-          tags_url = "https://registry.hub.docker.com/v2/moj/ruby/tags/list"
-          stub_request(:get, tags_url).
-            and_return(
-              status: 401,
-              body: "",
-              headers: { "www_authenticate" => "basic 123" }
-            )
-        end
-
-        it "raises a to PrivateSourceAuthenticationFailure error" do
-          error_class = Dependabot::PrivateSourceAuthenticationFailure
-          expect { checker.latest_version }.
-            to raise_error(error_class) do |error|
-              expect(error.source).to eq("registry.hub.docker.com")
-            end
-        end
-      end
-    end
-
-    context "when the latest version is a pre-release" do
-      let(:dependency_name) { "python" }
-      let(:version) { "3.5" }
-      let(:tags_fixture_name) { "python.json" }
-      before do
-        tags_url = "https://registry.hub.docker.com/v2/library/python/tags/list"
-        stub_request(:get, tags_url).
-          and_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("3.6.3") }
-
-      context "and the current version is a pre-release" do
-        let(:version) { "3.7.0a1" }
-        it { is_expected.to eq("3.7.0a2") }
-      end
-    end
-
-    context "when the latest tag points to an older version" do
-      let(:tags_fixture_name) { "dotnet.json" }
-      let(:headers_response) do
-        fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-      end
-      let(:version) { "2.0-sdk" }
-      let(:latest_versions) { %w(2-sdk 2.1-sdk 2.1.401-sdk) }
-
-      before do
-        stub_request(:head, repo_url + "manifests/2.2-sdk").
-          and_return(
-            status: 200,
-            body: "",
-            headers: JSON.parse(headers_response)
-          )
-
-        # Stub the latest version to return a different digest
-        [*latest_versions, "latest"].each do |version|
-          stub_request(:head, repo_url + "manifests/#{version}").
-            and_return(
-              status: 200,
-              body: "",
-              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
-            )
-        end
-      end
-
-      it { is_expected.to eq("2.1.401-sdk") }
-
-      context "and a suffix" do
-        let(:version) { "2.0-runtime" }
-        it { is_expected.to eq("2.1.3-runtime") }
-      end
-
-      context "with a paginated response" do
-        let(:pagination_headers) do
-          fixture("docker", "registry_pagination_headers", "next_link.json")
-        end
-        let(:end_pagination_headers) do
-          fixture("docker", "registry_pagination_headers", "no_next_link.json")
-        end
-        before do
-          stub_request(:get, repo_url + "tags/list").
-            and_return(
-              status: 200,
-              body: fixture("docker", "registry_tags", "dotnet_page_1.json"),
-              headers: JSON.parse(pagination_headers)
-            )
-          last = "ukD72mdD/mC8b5xV3susmJzzaTgp3hKwR9nRUW1yZZ6dLc5kfZtKLT2ICo63"\
-                 "WYvt2jq2VyIS3LWB%2Bo9HjGuiYQ6hARJz1jTFdW4jEMKPIg4kRwXypd7HXj"\
-                 "/SnA9iMm3YvNsd4LmPQrO4fpYZgnZZ8rzIIYqex6%2B3A3/mKcTsNKkKDV9V"\
-                 "R3ic6RJjYFCMOEk5/eqsfLaCDYEbtCNoxE2fBDwlzIl/W14f/F%2Bb%2BtQR"\
-                 "Gh3eUKE9nBJpVvAfibAEs215m4ePJm%2BNuVktVjHOYlRG3U03ekr1T7CPD1"\
-                 "Q%2B65wVYi0y2nCIl1/V40nkgG2WX5viYDxUuk3nEdnf55GUocnt38sDZzqB"\
-                 "nyglM9jvbxBzlO8="
-          stub_request(:get, repo_url + "tags/list?last=#{last}").
-            and_return(
-              status: 200,
-              body: fixture("docker", "registry_tags", "dotnet_page_2.json"),
-              headers: JSON.parse(end_pagination_headers)
-            )
-        end
-
-        it { is_expected.to eq("2.1.401-sdk") }
-      end
-
-      context "when the latest tag 404s" do
-        before do
-          stub_request(:head, repo_url + "manifests/latest").
-            to_return(status: 404).then.
-            to_return(
-              status: 200,
-              body: "",
-              headers: JSON.parse(headers_response.gsub("3ea1ca1", "4da71a2"))
-            )
-        end
-
-        it { is_expected.to eq("2.1.401-sdk") }
-
-        context "every time" do
-          before do
-            stub_request(:head, repo_url + "manifests/latest").
-              to_return(status: 404)
-          end
-
-          it { is_expected.to eq("2.2-sdk") }
-        end
-      end
-    end
-
-    context "when the dependency's version has a suffix with periods" do
-      let(:dependency_name) { "python" }
-      let(:version) { "3.6.2-alpine3.6" }
-      let(:tags_fixture_name) { "python.json" }
-      before do
-        tags_url = "https://registry.hub.docker.com/v2/library/python/tags/list"
-        stub_request(:get, tags_url).
-          and_return(status: 200, body: registry_tags)
-      end
-
-      it { is_expected.to eq("3.6.3-alpine3.6") }
-    end
-
-    context "when the dependency has a private registry" do
-      let(:dependency_name) { "ubuntu" }
-      let(:dependency) do
-        Dependabot::Dependency.new(
-          name: dependency_name,
-          version: version,
-          requirements: [{
-            requirement: nil,
-            groups: [],
-            file: "Dockerfile",
-            source: { registry: "registry-host.io:5000" }
-          }],
-          package_manager: "docker"
-        )
-      end
-      let(:tags_fixture_name) { "ubuntu_no_latest.json" }
-
-      context "without authentication credentials" do
-        before do
-          tags_url = "https://registry-host.io:5000/v2/ubuntu/tags/list"
-          stub_request(:get, tags_url).
-            and_return(
-              status: 401,
-              body: "",
-              headers: { "www_authenticate" => "basic 123" }
-            )
-        end
-
-        it "raises a to PrivateSourceAuthenticationFailure error" do
-          error_class = Dependabot::PrivateSourceAuthenticationFailure
-          expect { checker.latest_version }.
-            to raise_error(error_class) do |error|
-              expect(error.source).to eq("registry-host.io:5000")
-            end
-        end
-      end
-
-      context "with authentication credentials" do
-        let(:credentials) do
-          [{
-            "type" => "git_source",
-            "host" => "github.com",
-            "username" => "x-access-token",
-            "password" => "token"
-          }, {
-            "type" => "docker_registry",
-            "registry" => "registry-host.io:5000",
-            "username" => "grey",
-            "password" => "pa55word"
-          }]
-        end
-
-        before do
-          tags_url = "https://registry-host.io:5000/v2/ubuntu/tags/list"
-          stub_request(:get, tags_url).
-            and_return(status: 200, body: registry_tags)
-        end
-
-        it { is_expected.to eq("17.10") }
-
-        context "that don't have a username or password" do
-          let(:credentials) do
-            [{
-              "type" => "git_source",
-              "host" => "github.com",
-              "username" => "x-access-token",
-              "password" => "token"
-            }, {
-              "type" => "docker_registry",
-              "registry" => "registry-host.io:5000"
-            }]
-          end
-
-          it { is_expected.to eq("17.10") }
-        end
-      end
-    end
-  end
-
-  describe "#latest_resolvable_version" do
-    subject { checker.latest_resolvable_version }
-
-    before { allow(checker).to receive(:latest_version).and_return("delegate") }
-    it { is_expected.to eq("delegate") }
-  end
-
-  describe "#updated_requirements" do
-    subject { checker.updated_requirements }
-
-    context "when specified with a tag" do
-      let(:source) { { tag: version } }
-
-      it "updates the tag" do
-        expect(checker.updated_requirements).
-          to eq(
-            [{
-              requirement: nil,
-              groups: [],
-              file: "Dockerfile",
-              source: { tag: "17.10" }
-            }]
-          )
-      end
-    end
-
-    context "when specified with a digest" do
-      let(:source) { { digest: "old_digest" } }
-
-      before do
-        new_headers =
-          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-        stub_request(:head, repo_url + "manifests/17.10").
-          and_return(status: 200, body: "", headers: JSON.parse(new_headers))
-      end
-
-      it "updates the digest" do
-        expect(checker.updated_requirements).
-          to eq(
-            [{
-              requirement: nil,
-              groups: [],
-              file: "Dockerfile",
-              source: {
-                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
-                        "ca97eba880ebf600d68608"
-              }
-            }]
-          )
-      end
-    end
-
-    context "when specified with a digest and a tag" do
-      let(:source) { { digest: "old_digest", tag: "17.04" } }
-
-      before do
-        new_headers =
-          fixture("docker", "registry_manifest_headers", "ubuntu_17.10.json")
-        stub_request(:head, repo_url + "manifests/17.10").
-          and_return(status: 200, body: "", headers: JSON.parse(new_headers))
-      end
-
-      it "updates the tag and the digest" do
-        expect(checker.updated_requirements).
-          to eq(
-            [{
-              requirement: nil,
-              groups: [],
-              file: "Dockerfile",
-              source: {
-                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
-                        "ca97eba880ebf600d68608",
-                tag: "17.10"
-              }
-            }]
-          )
-      end
-    end
-  end
+  let(:package_manager) { "docker" }
+  let(:file_name) { "Dockerfile" }
 end
diff --git a/docker/spec/dependabot/docker_compose/file_fetcher_spec.rb b/docker/spec/dependabot/docker_compose/file_fetcher_spec.rb
new file mode 100644
index 0000000000..f5e13eb5ef
--- /dev/null
+++ b/docker/spec/dependabot/docker_compose/file_fetcher_spec.rb
@@ -0,0 +1,167 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/docker_compose/file_fetcher"
+require_common_spec "file_fetchers/shared_examples_for_file_fetchers"
+
+RSpec.describe Dependabot::DockerCompose::FileFetcher do
+  it_behaves_like "a dependency file fetcher"
+
+  let(:source) do
+    Dependabot::Source.new(
+      provider: "github",
+      repo: "gocardless/bump",
+      directory: directory
+    )
+  end
+  let(:file_fetcher_instance) do
+    described_class.new(source: source, credentials: credentials)
+  end
+  let(:directory) { "/" }
+  let(:github_url) { "https://api.github.com/" }
+  let(:url) { github_url + "repos/gocardless/bump/contents/" }
+  let(:credentials) do
+    [{
+      "type" => "git_source",
+      "host" => "github.com",
+      "username" => "x-access-token",
+      "password" => "token"
+    }]
+  end
+
+  before { allow(file_fetcher_instance).to receive(:commit).and_return("sha") }
+
+  context "with a docker-compose.yml file" do
+    before do
+      stub_request(:get, url + "?ref=sha").
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: fixture("github", "contents_docker_repo.json"),
+          headers: { "content-type" => "application/json" }
+        )
+
+      stub_request(:get, File.join(url, "docker-compose.yml?ref=sha")).
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: composefile_fixture,
+          headers: { "content-type" => "application/json" }
+        )
+    end
+
+    let(:composefile_fixture) do
+      fixture("github", "contents_docker-compose.json")
+    end
+
+    it "fetches the docker-compose.yml file" do
+      expect(file_fetcher_instance.files.count).to eq(1)
+      expect(file_fetcher_instance.files.map(&:name)).
+        to match_array(%w(docker-compose.yml))
+    end
+
+    context "that has an invalid encoding" do
+      let(:composefile_fixture) { fixture("github", "contents_image.json") }
+
+      it "raises a helpful error" do
+        expect { file_fetcher_instance.files }.
+          to raise_error(Dependabot::DependencyFileNotParseable)
+      end
+    end
+  end
+
+  context "with docker-compose.yml override file" do
+    before do
+      stub_request(:get, url + "?ref=sha").
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: fixture("github", "contents_docker_repo_multiple.json"),
+          headers: { "content-type" => "application/json" }
+        )
+      stub_request(:get, File.join(url, "docker-compose.yml?ref=sha")).
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: composefile_fixture,
+          headers: { "content-type" => "application/json" }
+        )
+      stub_request(:get, File.join(url, "docker-compose.override.yml?ref=sha")).
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: composefile_2_fixture,
+          headers: { "content-type" => "application/json" }
+        )
+    end
+
+    let(:composefile_fixture) do
+      fixture("github", "contents_docker-compose.json")
+    end
+    let(:composefile_2_fixture) do
+      fixture("github", "contents_docker-compose.json")
+    end
+
+    it "fetches both docker-compose.yml files" do
+      expect(file_fetcher_instance.files.count).to eq(2)
+      expect(file_fetcher_instance.files.map(&:name)).
+        to match_array(%w(docker-compose.yml docker-compose.override.yml))
+    end
+
+    context "one of which has an invalid encoding" do
+      let(:composefile_2_fixture) { fixture("github", "contents_image.json") }
+
+      it "fetches the first docker-compose.yml file, "\
+         "and ignores the invalid one" do
+        expect(file_fetcher_instance.files.count).to eq(1)
+        expect(file_fetcher_instance.files.map(&:name)).
+          to match_array(%w(docker-compose.yml))
+      end
+    end
+  end
+
+  context "with a custom named docker-compose.yml file" do
+    before do
+      stub_request(:get, url + "?ref=sha").
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: fixture("github", "contents_docker_repo_custom.json"),
+          headers: { "content-type" => "application/json" }
+        )
+
+      stub_request(:get, File.join(url, "docker-compose.override.yml?ref=sha")).
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 200,
+          body: fixture("github", "contents_docker-compose.json"),
+          headers: { "content-type" => "application/json" }
+        )
+    end
+
+    it "fetches the docker-compose.override.yml file" do
+      expect(file_fetcher_instance.files.count).to eq(1)
+      expect(file_fetcher_instance.files.map(&:name)).
+        to match_array(%w(docker-compose.override.yml))
+    end
+  end
+
+  context "with a directory that doesn't exist" do
+    let(:directory) { "/non/existant" }
+
+    before do
+      stub_request(:get, url + "non/existant?ref=sha").
+        with(headers: { "Authorization" => "token token" }).
+        to_return(
+          status: 404,
+          body: fixture("github", "not_found.json"),
+          headers: { "content-type" => "application/json" }
+        )
+    end
+
+    it "raises a helpful error" do
+      expect { file_fetcher_instance.files }.
+        to raise_error(Dependabot::DependencyFileNotFound)
+    end
+  end
+end
diff --git a/docker/spec/dependabot/docker_compose/file_parser_spec.rb b/docker/spec/dependabot/docker_compose/file_parser_spec.rb
new file mode 100644
index 0000000000..b395f4fc97
--- /dev/null
+++ b/docker/spec/dependabot/docker_compose/file_parser_spec.rb
@@ -0,0 +1,591 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/dependency_file"
+require "dependabot/source"
+require "dependabot/docker_compose/file_parser"
+require_common_spec "file_parsers/shared_examples_for_file_parsers"
+
+RSpec.describe Dependabot::DockerCompose::FileParser do
+  it_behaves_like "a dependency file parser"
+
+  let(:files) { [composefile] }
+  let(:composefile) do
+    Dependabot::DependencyFile.new(
+      name: "docker-compose.yml",
+      content: composefile_body
+    )
+  end
+  let(:composefile_body) do
+    fixture("docker_compose", "composefiles", composefile_fixture_name)
+  end
+  let(:composefile_fixture_name) { "tag" }
+  let(:parser) { described_class.new(dependency_files: files, source: source) }
+  let(:source) do
+    Dependabot::Source.new(
+      provider: "github",
+      repo: "gocardless/bump",
+      directory: "/"
+    )
+  end
+
+  describe "parse" do
+    subject(:dependencies) { parser.parse }
+
+    its(:length) { is_expected.to eq(1) }
+
+    describe "the first dependency" do
+      subject(:dependency) { dependencies.first }
+      let(:expected_requirements) do
+        [{
+          requirement: nil,
+          groups: [],
+          file: "docker-compose.yml",
+          source: { tag: "17.04" }
+        }]
+      end
+
+      it "has the right details" do
+        expect(dependency).to be_a(Dependabot::Dependency)
+        expect(dependency.name).to eq("ubuntu")
+        expect(dependency.version).to eq("17.04")
+        expect(dependency.requirements).to eq(expected_requirements)
+      end
+    end
+
+    context "with no tag or digest" do
+      let(:composefile_fixture_name) { "bare" }
+      its(:length) { is_expected.to eq(0) }
+    end
+
+    context "with a namespace" do
+      let(:composefile_fixture_name) { "namespace" }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("my-fork/ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+    end
+
+    context "with a non-numeric version" do
+      let(:composefile_fixture_name) { "non_numeric_version" }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "artful" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("ubuntu")
+          expect(dependency.version).to eq("artful")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+    end
+
+    context "with a digest" do
+      let(:composefile_fixture_name) { "digest" }
+      let(:registry_tags) { fixture("docker", "registry_tags", "ubuntu.json") }
+      let(:digest_headers) do
+        JSON.parse(
+          fixture("docker", "registry_manifest_headers", "ubuntu_12.04.5.json")
+        )
+      end
+
+      let(:repo_url) { "https://registry.hub.docker.com/v2/library/ubuntu/" }
+
+      before do
+        auth_url = "https://auth.docker.io/token?service=registry.docker.io"
+        stub_request(:get, auth_url).
+          and_return(status: 200, body: { token: "token" }.to_json)
+
+        tags_url = repo_url + "tags/list"
+        stub_request(:get, tags_url).
+          and_return(status: 200, body: registry_tags)
+      end
+
+      context "that doesn't match any tags" do
+        let(:registry_tags) do
+          fixture("docker", "registry_tags", "small_ubuntu.json")
+        end
+        before { digest_headers["docker_content_digest"] = "nomatch" }
+
+        before do
+          ubuntu_url = "https://registry.hub.docker.com/v2/library/ubuntu/"
+          stub_request(:head, /#{Regexp.quote(ubuntu_url)}manifests/).
+            and_return(status: 200, body: "", headers: digest_headers)
+        end
+
+        its(:length) { is_expected.to eq(0) }
+      end
+
+      context "that matches a tag" do
+        before do
+          stub_request(:head, repo_url + "manifests/10.04").
+            and_return(status: 404)
+
+          stub_request(:head, repo_url + "manifests/12.04.5").
+            and_return(status: 200, body: "", headers: digest_headers)
+        end
+
+        its(:length) { is_expected.to eq(1) }
+
+        describe "the first dependency" do
+          subject(:dependency) { dependencies.first }
+          let(:expected_requirements) do
+            [{
+              requirement: nil,
+              groups: [],
+              file: "docker-compose.yml",
+              source: {
+                digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8d"\
+                        "fc38288cf73aa07485005"
+              }
+            }]
+          end
+
+          it "has the right details" do
+            expect(dependency).to be_a(Dependabot::Dependency)
+            expect(dependency.name).to eq("ubuntu")
+            expect(dependency.version).to eq("12.04.5")
+            expect(dependency.requirements).to eq(expected_requirements)
+          end
+        end
+
+        context "for a private registry" do
+          let(:composefile_fixture_name) { "private_digest" }
+          let(:repo_url) { "https://registry-host.io:5000/v2/myreg/ubuntu/" }
+
+          context "without no/bad authentication credentials" do
+            before do
+              tags_url = repo_url + "tags/list"
+              stub_request(:get, tags_url).
+                and_return(
+                  status: 401,
+                  body: "",
+                  headers: { "www_authenticate" => "basic 123" }
+                )
+            end
+
+            it "raises a PrivateSourceAuthenticationFailure error" do
+              error_class = Dependabot::PrivateSourceAuthenticationFailure
+              expect { parser.parse }.
+                to raise_error(error_class) do |error|
+                  expect(error.source).to eq("registry-host.io:5000")
+                end
+            end
+          end
+
+          context "with good authentication credentials" do
+            let(:parser) do
+              described_class.new(
+                dependency_files: files,
+                credentials: credentials,
+                source: source
+              )
+            end
+            let(:credentials) do
+              [{
+                "type" => "docker_registry",
+                "registry" => "registry-host.io:5000",
+                "username" => "grey",
+                "password" => "pa55word"
+              }]
+            end
+
+            its(:length) { is_expected.to eq(1) }
+
+            describe "the first dependency" do
+              subject(:dependency) { dependencies.first }
+              let(:expected_requirements) do
+                [{
+                  requirement: nil,
+                  groups: [],
+                  file: "docker-compose.yml",
+                  source: {
+                    registry: "registry-host.io:5000",
+                    digest: "sha256:18305429afa14ea462f810146ba44d4363ae76"\
+                            "e4c8dfc38288cf73aa07485005"
+                  }
+                }]
+              end
+
+              it "has the right details" do
+                expect(dependency).to be_a(Dependabot::Dependency)
+                expect(dependency.name).to eq("myreg/ubuntu")
+                expect(dependency.version).to eq("12.04.5")
+                expect(dependency.requirements).to eq(expected_requirements)
+              end
+            end
+
+            context "that don't include a username and password" do
+              let(:credentials) do
+                [{
+                  "type" => "docker_registry",
+                  "registry" => "registry-host.io:5000"
+                }]
+              end
+
+              its(:length) { is_expected.to eq(1) }
+            end
+          end
+
+          context "that uses Amazon ECR" do
+            let(:composefile_fixture_name) { "private_ecr_digest" }
+            let(:repo_url) do
+              "https://695729449481.dkr.ecr.eu-west-2.amazonaws.com/v2/"\
+              "docker-php/"
+            end
+
+            context "without credentials" do
+              before do
+                tags_url = repo_url + "tags/list"
+                stub_request(:get, tags_url).
+                  and_return(
+                    status: 401,
+                    body: "",
+                    headers: { "www_authenticate" => "basic 123" }
+                  )
+              end
+
+              it "raises a PrivateSourceAuthenticationFailure error" do
+                error_class = Dependabot::PrivateSourceAuthenticationFailure
+                expect { parser.parse }.
+                  to raise_error(error_class) do |error|
+                    expect(error.source).
+                      to eq("695729449481.dkr.ecr.eu-west-2.amazonaws.com")
+                  end
+              end
+            end
+
+            context "with credentials" do
+              let(:parser) do
+                described_class.new(
+                  dependency_files: files,
+                  credentials: credentials,
+                  source: source
+                )
+              end
+
+              let(:credentials) do
+                [{
+                  "type" => "docker_registry",
+                  "registry" => "695729449481.dkr.ecr.eu-west-2.amazonaws.com",
+                  "username" => "grey",
+                  "password" => "pa55word"
+                }]
+              end
+
+              context "that are invalid" do
+                before do
+                  stub_request(
+                    :post,
+                    "https://api.ecr.eu-west-2.amazonaws.com/"
+                  ).and_return(
+                    status: 403,
+                    body: fixture("docker", "ecr_responses", "invalid_token")
+                  )
+                end
+
+                it "raises a PrivateSourceAuthenticationFailure error" do
+                  error_class = Dependabot::PrivateSourceAuthenticationFailure
+                  expect { parser.parse }.
+                    to raise_error(error_class) do |error|
+                      expect(error.source).
+                        to eq("695729449481.dkr.ecr.eu-west-2.amazonaws.com")
+                    end
+                end
+              end
+
+              context "that are valid" do
+                before do
+                  stub_request(
+                    :post,
+                    "https://api.ecr.eu-west-2.amazonaws.com/"
+                  ).and_return(
+                    status: 200,
+                    body: fixture("docker", "ecr_responses", "auth_data")
+                  )
+                end
+
+                its(:length) { is_expected.to eq(1) }
+
+                describe "the first dependency" do
+                  subject(:dependency) { dependencies.first }
+                  let(:expected_requirements) do
+                    [{
+                      requirement: nil,
+                      groups: [],
+                      file: "docker-compose.yml",
+                      source: {
+                        registry:
+                          "695729449481.dkr.ecr.eu-west-2.amazonaws.com",
+                        digest: "sha256:18305429afa14ea462f810146ba44d4363ae76"\
+                                "e4c8dfc38288cf73aa07485005"
+                      }
+                    }]
+                  end
+
+                  it "has the right details" do
+                    expect(dependency).to be_a(Dependabot::Dependency)
+                    expect(dependency.name).to eq("docker-php")
+                    expect(dependency.version).to eq("12.04.5")
+                    expect(dependency.requirements).to eq(expected_requirements)
+                  end
+                end
+              end
+            end
+          end
+        end
+      end
+    end
+
+    context "with multiple services" do
+      let(:composefile_fixture_name) { "multiple" }
+
+      its(:length) { is_expected.to eq(2) }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+
+      describe "the second dependency" do
+        subject(:dependency) { dependencies.last }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "3.6.3" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("python")
+          expect(dependency.version).to eq("3.6.3")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+
+      context "that are identical" do
+        let(:composefile_fixture_name) { "multiple_identical" }
+
+        its(:length) { is_expected.to eq(1) }
+
+        describe "the first dependency" do
+          subject(:dependency) { dependencies.first }
+          let(:expected_requirements) do
+            [{
+              requirement: nil,
+              groups: [],
+              file: "docker-compose.yml",
+              source: { tag: "10-alpine" }
+            }]
+          end
+
+          it "has the right details" do
+            expect(dependency).to be_a(Dependabot::Dependency)
+            expect(dependency.name).to eq("node")
+            expect(dependency.version).to eq("10-alpine")
+            expect(dependency.requirements).to eq(expected_requirements)
+          end
+        end
+      end
+    end
+
+    context "with a v1 dockerhub reference and a tag" do
+      let(:composefile_fixture_name) { "v1_tag" }
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("myreg/ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+    end
+
+    context "with a private registry and a tag" do
+      let(:composefile_fixture_name) { "private_tag" }
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              registry: "registry-host.io:5000",
+              tag: "17.04"
+            }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("myreg/ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+
+      context "when the registry has no port" do
+        let(:composefile_fixture_name) { "private_no_port" }
+        its(:length) { is_expected.to eq(1) }
+
+        describe "the first dependency" do
+          subject(:dependency) { dependencies.first }
+          let(:expected_requirements) do
+            [{
+              requirement: nil,
+              groups: [],
+              file: "docker-compose.yml",
+              source: {
+                registry: "aws-account-id.dkr.ecr.region.amazonaws.com",
+                tag: "17.04"
+              }
+            }]
+          end
+
+          it "has the right details" do
+            expect(dependency).to be_a(Dependabot::Dependency)
+            expect(dependency.name).to eq("myreg/ubuntu")
+            expect(dependency.version).to eq("17.04")
+            expect(dependency.requirements).to eq(expected_requirements)
+          end
+        end
+      end
+    end
+
+    context "with a non-standard filename" do
+      let(:composefile) do
+        Dependabot::DependencyFile.new(
+          name: "custom-name",
+          content: composefile_body
+        )
+      end
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "custom-name",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        its(:requirements) { is_expected.to eq(expected_requirements) }
+      end
+    end
+
+    context "with multiple composefiles" do
+      let(:files) { [composefile, dockefile2] }
+      let(:dockefile2) do
+        Dependabot::DependencyFile.new(
+          name: "custom-name",
+          content: composefile_body2
+        )
+      end
+      let(:composefile_body2) do
+        fixture("docker_compose", "composefiles", "namespace")
+      end
+
+      its(:length) { is_expected.to eq(2) }
+
+      describe "the first dependency" do
+        subject(:dependency) { dependencies.first }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+
+      describe "the second dependency" do
+        subject(:dependency) { dependencies.last }
+        let(:expected_requirements) do
+          [{
+            requirement: nil,
+            groups: [],
+            file: "custom-name",
+            source: { tag: "17.04" }
+          }]
+        end
+
+        it "has the right details" do
+          expect(dependency).to be_a(Dependabot::Dependency)
+          expect(dependency.name).to eq("my-fork/ubuntu")
+          expect(dependency.version).to eq("17.04")
+          expect(dependency.requirements).to eq(expected_requirements)
+        end
+      end
+    end
+  end
+end
diff --git a/docker/spec/dependabot/docker_compose/file_updater_spec.rb b/docker/spec/dependabot/docker_compose/file_updater_spec.rb
new file mode 100644
index 0000000000..c0bd065397
--- /dev/null
+++ b/docker/spec/dependabot/docker_compose/file_updater_spec.rb
@@ -0,0 +1,477 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "yaml"
+require "dependabot/dependency"
+require "dependabot/dependency_file"
+require "dependabot/source"
+require "dependabot/docker_compose/file_updater"
+require_common_spec "file_updaters/shared_examples_for_file_updaters"
+
+RSpec.describe Dependabot::DockerCompose::FileUpdater do
+  it_behaves_like "a dependency file updater"
+
+  let(:updater) do
+    described_class.new(
+      dependency_files: files,
+      dependencies: [dependency],
+      credentials: credentials
+    )
+  end
+  let(:files) { [dockerfile] }
+  let(:credentials) do
+    [{
+      "type" => "git_source",
+      "host" => "github.com",
+      "username" => "x-access-token",
+      "password" => "token"
+    }]
+  end
+  let(:dockerfile) do
+    Dependabot::DependencyFile.new(
+      content: dockerfile_body,
+      name: "docker-compose.yml"
+    )
+  end
+  let(:dockerfile_body) do
+    fixture("docker_compose", "composefiles", "multiple")
+  end
+  let(:dependency) do
+    Dependabot::Dependency.new(
+      name: "ubuntu",
+      version: "17.10",
+      previous_version: "17.04",
+      requirements: [{
+        requirement: nil,
+        groups: [],
+        file: "docker-compose.yml",
+        source: { tag: "17.10" }
+      }],
+      previous_requirements: [{
+        requirement: nil,
+        groups: [],
+        file: "docker-compose.yml",
+        source: { tag: "17.04" }
+      }],
+      package_manager: "docker"
+    )
+  end
+
+  describe "#updated_dependency_files" do
+    subject(:updated_files) { updater.updated_dependency_files }
+
+    it "returns DependencyFile objects" do
+      updated_files.each { |f| expect(f).to be_a(Dependabot::DependencyFile) }
+    end
+
+    its(:length) { is_expected.to eq(1) }
+
+    describe "the updated docker-compose.yml" do
+      subject(:updated_dockerfile) do
+        updated_files.find { |f| f.name == "docker-compose.yml" }
+      end
+      let(:yaml_content) do
+        YAML.safe_load updated_dockerfile.content
+      end
+
+      its(:content) { is_expected.to include "image: ubuntu:17.10\n" }
+      its(:content) { is_expected.to include "image: python:3.6.3\n" }
+      it "should contain the expected YAML content" do
+        expect(yaml_content).to eq(
+          "version" => "2",
+          "services" => {
+            "interpreter" => { "image" => "python:3.6.3" },
+            "os" => { "image" => "ubuntu:17.10" }
+          }
+        )
+      end
+    end
+
+    context "when multiple identical lines need to be updated" do
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "multiple_identical")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "node",
+          version: "10.9-alpine",
+          previous_version: "10-alpine",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "10.9-alpine" }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "10-alpine" }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      describe "the updated docker-compose.yml" do
+        subject(:updated_dockerfile) do
+          updated_files.find { |f| f.name == "docker-compose.yml" }
+        end
+
+        its(:content) { is_expected.to include "image: node:10.9-alpine\n" }
+        its(:content) { is_expected.to include "node-2:" }
+      end
+    end
+
+    context "when the dependency has a namespace" do
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "namespace")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "my-fork/ubuntu",
+          version: "17.10",
+          previous_version: "17.04",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.10" }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the updated docker-compose.yml" do
+        subject(:updated_dockerfile) do
+          updated_files.find { |f| f.name == "docker-compose.yml" }
+        end
+
+        its(:content) { is_expected.to include "image: my-fork/ubuntu:17.10\n" }
+        its(:content) do
+          is_expected.to include "command: [/bin/echo, 'Hello world']"
+        end
+      end
+    end
+
+    context "when the dependency is from a private registry" do
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "private_tag")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "myreg/ubuntu",
+          version: "17.10",
+          previous_version: "17.04",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              registry: "registry-host.io:5000",
+              tag: "17.10"
+            }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              registry: "registry-host.io:5000",
+              tag: "17.04"
+            }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the updated docker-compose.yml" do
+        subject(:updated_dockerfile) do
+          updated_files.find { |f| f.name == "docker-compose.yml" }
+        end
+
+        its(:content) do
+          is_expected.
+            to include("image: registry-host.io:5000/myreg/ubuntu:17.10\n")
+        end
+        its(:content) do
+          is_expected.to include "command: [/bin/echo, 'Hello world']"
+        end
+      end
+    end
+
+    context "when the dependency is docker-compose.yml using the v1 API" do
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "v1_tag")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "myreg/ubuntu",
+          version: "17.10",
+          previous_version: "17.04",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.10" }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: { tag: "17.04" }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the updated docker-compose.yml" do
+        subject(:updated_dockerfile) do
+          updated_files.find { |f| f.name == "docker-compose.yml" }
+        end
+
+        its(:content) do
+          is_expected.
+            to include("image: docker.io/myreg/ubuntu:17.10\n")
+        end
+        its(:content) do
+          is_expected.to include "command: [/bin/echo, 'Hello world']"
+        end
+      end
+    end
+
+    context "when the dependency has a digest" do
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "digest")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "ubuntu",
+          version: "17.10",
+          previous_version: "12.04.5",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                      "ca97eba880ebf600d68608"
+            }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8"\
+                      "dfc38288cf73aa07485005"
+            }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      its(:length) { is_expected.to eq(1) }
+
+      describe "the updated docker-compose.yml" do
+        subject(:updated_dockerfile) do
+          updated_files.find { |f| f.name == "docker-compose.yml" }
+        end
+
+        its(:content) do
+          is_expected.to include "image: ubuntu@sha256:3ea1ca1aa"
+        end
+        its(:content) do
+          is_expected.to include "command: [/bin/echo, 'Hello world']"
+        end
+
+        context "when the dockerfile has a tag as well as a digest" do
+          let(:dockerfile_body) do
+            fixture("docker_compose", "composefiles", "digest_and_tag")
+          end
+
+          its(:content) do
+            is_expected.to include "image: ubuntu:17.10@sha256:3ea1ca1aa"
+          end
+        end
+      end
+
+      context "when the dependency has a private registry" do
+        let(:dockerfile_body) do
+          fixture("docker_compose", "composefiles", "private_digest")
+        end
+        let(:dependency) do
+          Dependabot::Dependency.new(
+            name: "myreg/ubuntu",
+            version: "17.10",
+            previous_version: "17.10",
+            requirements: [{
+              requirement: nil,
+              groups: [],
+              file: "docker-compose.yml",
+              source: {
+                registry: "registry-host.io:5000",
+                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                        "ca97eba880ebf600d68608"
+              }
+            }],
+            previous_requirements: [{
+              requirement: nil,
+              groups: [],
+              file: "docker-compose.yml",
+              source: {
+                registry: "registry-host.io:5000",
+                digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8"\
+                        "dfc38288cf73aa07485005"
+              }
+            }],
+            package_manager: "docker"
+          )
+        end
+
+        its(:length) { is_expected.to eq(1) }
+
+        describe "the updated docker-compose.yml" do
+          subject(:updated_dockerfile) do
+            updated_files.find { |f| f.name == "docker-compose.yml" }
+          end
+
+          its(:content) do
+            is_expected.to include("image: registry-host.io:5000/"\
+                                   "myreg/ubuntu@sha256:3ea1ca1aa")
+          end
+          its(:content) do
+            is_expected.to include "command: [/bin/echo, 'Hello world']"
+          end
+        end
+      end
+    end
+
+    context "when multiple dockerfiles to be updated" do
+      let(:files) { [dockerfile, dockefile2] }
+      let(:dockefile2) do
+        Dependabot::DependencyFile.new(
+          name: "custom-name",
+          content: dockerfile_body2
+        )
+      end
+      let(:dockerfile_body) do
+        fixture("docker_compose", "composefiles", "digest")
+      end
+      let(:dockerfile_body2) do
+        fixture("docker_compose", "composefiles", "digest_and_tag")
+      end
+      let(:dependency) do
+        Dependabot::Dependency.new(
+          name: "ubuntu",
+          version: "17.10",
+          previous_version: "12.04.5",
+          requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                      "ca97eba880ebf600d68608"
+            }
+          }, {
+            requirement: nil,
+            groups: [],
+            file: "custom-name",
+            source: {
+              digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                      "ca97eba880ebf600d68608",
+              tag: "17.10"
+            }
+          }],
+          previous_requirements: [{
+            requirement: nil,
+            groups: [],
+            file: "docker-compose.yml",
+            source: {
+              digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8"\
+                      "dfc38288cf73aa07485005"
+            }
+          }, {
+            requirement: nil,
+            groups: [],
+            file: "custom-name",
+            source: {
+              digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8"\
+                      "dfc38288cf73aa07485005",
+              tag: "12.04.5"
+            }
+          }],
+          package_manager: "docker"
+        )
+      end
+
+      describe "the updated docker-compose.yml" do
+        subject { updated_files.find { |f| f.name == "docker-compose.yml" } }
+        its(:content) do
+          is_expected.to include "image: ubuntu@sha256:3ea1ca1aa"
+        end
+      end
+
+      describe "the updated custom-name file" do
+        subject { updated_files.find { |f| f.name == "custom-name" } }
+
+        its(:content) do
+          is_expected.to include "image: ubuntu:17.10@sha256:3ea1ca1aa"
+        end
+      end
+
+      context "when only one needs updating" do
+        let(:dockerfile_body) do
+          fixture("docker_compose", "composefiles", "bare")
+        end
+
+        let(:dependency) do
+          Dependabot::Dependency.new(
+            name: "ubuntu",
+            version: "17.10",
+            previous_version: "12.04.5",
+            requirements: [{
+              requirement: nil,
+              groups: [],
+              file: "custom-name",
+              source: {
+                digest: "sha256:3ea1ca1aa8483a38081750953ad75046e6cc9f6b86"\
+                        "ca97eba880ebf600d68608"
+              }
+            }],
+            previous_requirements: [{
+              requirement: nil,
+              groups: [],
+              file: "custom-name",
+              source: {
+                digest: "sha256:18305429afa14ea462f810146ba44d4363ae76e4c8"\
+                        "dfc38288cf73aa07485005"
+              }
+            }],
+            package_manager: "docker"
+          )
+        end
+
+        describe "the updated custom-name file" do
+          subject { updated_files.find { |f| f.name == "custom-name" } }
+
+          its(:content) do
+            is_expected.to include "image: ubuntu:17.10@sha256:3ea1ca1aa"
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/docker/spec/dependabot/docker_compose/update_checker_spec.rb b/docker/spec/dependabot/docker_compose/update_checker_spec.rb
new file mode 100644
index 0000000000..68887043c1
--- /dev/null
+++ b/docker/spec/dependabot/docker_compose/update_checker_spec.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/docker_compose/update_checker"
+require "dependabot/docker/common/shared_examples_for_docker_update_checkers.rb"
+
+RSpec.describe Dependabot::DockerCompose::UpdateChecker do
+  it_behaves_like "a Docker update checker"
+
+  let(:package_manager) { "docker_compose" }
+  let(:file_name) { "docker-compose.yml" }
+end
diff --git a/docker/spec/dependabot/docker_compose_spec.rb b/docker/spec/dependabot/docker_compose_spec.rb
new file mode 100644
index 0000000000..e0c3dc81fc
--- /dev/null
+++ b/docker/spec/dependabot/docker_compose_spec.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+require "dependabot/docker_compose"
+require_common_spec "shared_examples_for_autoloading"
+
+RSpec.describe Dependabot::DockerCompose do
+  it_behaves_like "it registers the required classes", "docker_compose"
+end
diff --git a/docker/spec/fixtures/docker_compose/composefiles/bare b/docker/spec/fixtures/docker_compose/composefiles/bare
new file mode 100644
index 0000000000..066287521d
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/bare
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: ubuntu
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/digest b/docker/spec/fixtures/docker_compose/composefiles/digest
new file mode 100644
index 0000000000..93b585ced9
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/digest
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: ubuntu@sha256:18305429afa14ea462f810146ba44d4363ae76e4c8dfc38288cf73aa07485005
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/digest_and_tag b/docker/spec/fixtures/docker_compose/composefiles/digest_and_tag
new file mode 100644
index 0000000000..9e3aeb0882
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/digest_and_tag
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: ubuntu:12.04.5@sha256:18305429afa14ea462f810146ba44d4363ae76e4c8dfc38288cf73aa07485005
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/multiple b/docker/spec/fixtures/docker_compose/composefiles/multiple
new file mode 100644
index 0000000000..fb7e79760b
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/multiple
@@ -0,0 +1,6 @@
+version: '2'
+services:
+  os:
+    image: ubuntu:17.04
+  interpreter:
+    image: python:3.6.3
diff --git a/docker/spec/fixtures/docker_compose/composefiles/multiple_identical b/docker/spec/fixtures/docker_compose/composefiles/multiple_identical
new file mode 100644
index 0000000000..b7b8ead64e
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/multiple_identical
@@ -0,0 +1,6 @@
+version: '2'
+services:
+  node-1:
+    image: node:10-alpine
+  node-2:
+    image: node:10-alpine
diff --git a/docker/spec/fixtures/docker_compose/composefiles/namespace b/docker/spec/fixtures/docker_compose/composefiles/namespace
new file mode 100644
index 0000000000..c1484ab7fc
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/namespace
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: my-fork/ubuntu:17.04
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/non_numeric_version b/docker/spec/fixtures/docker_compose/composefiles/non_numeric_version
new file mode 100644
index 0000000000..97e312804a
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/non_numeric_version
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: ubuntu:artful
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/private_digest b/docker/spec/fixtures/docker_compose/composefiles/private_digest
new file mode 100644
index 0000000000..2017b08be5
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/private_digest
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: registry-host.io:5000/myreg/ubuntu@sha256:18305429afa14ea462f810146ba44d4363ae76e4c8dfc38288cf73aa07485005
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/private_ecr_digest b/docker/spec/fixtures/docker_compose/composefiles/private_ecr_digest
new file mode 100644
index 0000000000..112545b53a
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/private_ecr_digest
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: 695729449481.dkr.ecr.eu-west-2.amazonaws.com/docker-php@sha256:18305429afa14ea462f810146ba44d4363ae76e4c8dfc38288cf73aa07485005
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/private_no_port b/docker/spec/fixtures/docker_compose/composefiles/private_no_port
new file mode 100644
index 0000000000..ca01a020d2
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/private_no_port
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: aws-account-id.dkr.ecr.region.amazonaws.com/myreg/ubuntu:17.04
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/private_tag b/docker/spec/fixtures/docker_compose/composefiles/private_tag
new file mode 100644
index 0000000000..374514ea03
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/private_tag
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: registry-host.io:5000/myreg/ubuntu:17.04
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/tag b/docker/spec/fixtures/docker_compose/composefiles/tag
new file mode 100644
index 0000000000..dce865acc7
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/tag
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: ubuntu:17.04
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/docker_compose/composefiles/v1_tag b/docker/spec/fixtures/docker_compose/composefiles/v1_tag
new file mode 100644
index 0000000000..e8d93a0235
--- /dev/null
+++ b/docker/spec/fixtures/docker_compose/composefiles/v1_tag
@@ -0,0 +1,5 @@
+version: '2'
+services:
+  hello_world:
+    image: docker.io/myreg/ubuntu:17.04
+    command: [/bin/echo, 'Hello world']
diff --git a/docker/spec/fixtures/github/contents_docker-compose.json b/docker/spec/fixtures/github/contents_docker-compose.json
new file mode 100644
index 0000000000..0faed57f5a
--- /dev/null
+++ b/docker/spec/fixtures/github/contents_docker-compose.json
@@ -0,0 +1,18 @@
+{
+  "name": "docker-compose.yml",
+  "path": "docker-compose.yml",
+  "sha": "311f9743315183cc6751313cb251cfeb3de45c1a",
+  "size": 4927,
+  "url": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.yml?ref=master",
+  "html_url": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.yml",
+  "git_url": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+  "download_url": "https://raw.githubusercontent.com/dependabot/dependabot-core/master/docker-compose.yml",
+  "type": "file",
+  "content": 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pbGVkLnppcCBcCiAgICAm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\nb2NhbC9ncmFkbGUvYmluOiRQQVRICg==\n",
+  "encoding": "base64",
+  "_links": {
+    "self": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.yml?ref=master",
+    "git": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+    "html": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.yml"
+  }
+}
diff --git a/docker/spec/fixtures/github/contents_docker_repo.json b/docker/spec/fixtures/github/contents_docker_repo.json
index 5eea29e2e0..af0288d5fc 100644
--- a/docker/spec/fixtures/github/contents_docker_repo.json
+++ b/docker/spec/fixtures/github/contents_docker_repo.json
@@ -111,6 +111,22 @@
       "html": "https://github.com/dependabot/dependabot-core/blob/master/Dockerfile"
     }
   },
+  {
+    "name": "docker-compose.yml",
+    "path": "docker-compose.yml",
+    "sha": "311f9743315183cc6751313cb251cfeb3de45c1a",
+    "size": 4927,
+    "url": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.yml?ref=master",
+    "html_url": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.yml",
+    "git_url": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+    "download_url": "https://raw.githubusercontent.com/dependabot/dependabot-core/master/docker-compose.yml",
+    "type": "file",
+    "_links": {
+      "self": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.yml?ref=master",
+      "git": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+      "html": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.yml"
+    }
+  },
   {
     "name": "Gemfile",
     "path": "Gemfile",
diff --git a/docker/spec/fixtures/github/contents_docker_repo_custom.json b/docker/spec/fixtures/github/contents_docker_repo_custom.json
index 68f8605e94..d963f665d7 100644
--- a/docker/spec/fixtures/github/contents_docker_repo_custom.json
+++ b/docker/spec/fixtures/github/contents_docker_repo_custom.json
@@ -111,6 +111,22 @@
       "html": "https://github.com/dependabot/dependabot-core/blob/master/Dockerfile-base"
     }
   },
+  {
+    "name": "docker-compose.override.yml",
+    "path": "docker-compose.override.yml",
+    "sha": "311f9743315183cc6751313cb251cfeb3de45c1a",
+    "size": 4927,
+    "url": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.override.yml?ref=master",
+    "html_url": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.override.yml",
+    "git_url": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+    "download_url": "https://raw.githubusercontent.com/dependabot/dependabot-core/master/docker-compose.override.yml",
+    "type": "file",
+    "_links": {
+      "self": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.override.yml?ref=master",
+      "git": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+      "html": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.override.yml"
+    }
+  },
   {
     "name": "Gemfile",
     "path": "Gemfile",
diff --git a/docker/spec/fixtures/github/contents_docker_repo_multiple.json b/docker/spec/fixtures/github/contents_docker_repo_multiple.json
index a34a38a029..6ed043c985 100644
--- a/docker/spec/fixtures/github/contents_docker_repo_multiple.json
+++ b/docker/spec/fixtures/github/contents_docker_repo_multiple.json
@@ -127,6 +127,38 @@
       "html": "https://github.com/dependabot/dependabot-core/blob/master/Dockerfile-base"
     }
   },
+  {
+    "name": "docker-compose.yml",
+    "path": "docker-compose.yml",
+    "sha": "311f9743315183cc6751313cb251cfeb3de45c1a",
+    "size": 4927,
+    "url": "https://api.github.com/repos/dependabot/dependabot-core/contents/docker-compose.yml?ref=master",
+    "html_url": "https://github.com/dependabot/dependabot-core/blob/master/docker-compose.yml",
+    "git_url": "https://api.github.com/repos/dependabot/dependabot-core/git/blobs/311f9743315183cc6751313cb251cfeb3de45c1a",
+    "download_url": "https://raw.githubusercontent.com/dependabot/dependabot-core/master/docker-compose.yml",
+    "type": "file",
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