diff --git a/.appveyor.yml b/.appveyor.yml
index 341823c..cafd74f 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -1,6 +1,6 @@
 environment:
   matrix:
-  - julia_version: 1.3
+  - julia_version: 1.6
   - julia_version: nightly
 
 platform:
diff --git a/.cirrus.yml b/.cirrus.yml
index c005d8c..41d6f75 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -4,7 +4,7 @@ task:
   name: FreeBSD
   env:
     matrix:
-      - JULIA_VERSION: 1.3
+      - JULIA_VERSION: 1.6
       - JULIA_VERSION: nightly
   allow_failures: $JULIA_VERSION == 'nightly'
   install_script:
diff --git a/.gitignore b/.gitignore
index eb7c30a..6b141a5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@ doc/_build/
 deps/deps.jl
 build.log
 deps/usr/*
+Manifest.toml
diff --git a/.travis.yml b/.travis.yml
index 0afcda1..16ecc27 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,7 @@ os:
     - osx
 
 julia:
-    - 1.3
+    - 1.6
     - nightly
 
 matrix:
diff --git a/Project.toml b/Project.toml
index 91750a8..b707069 100644
--- a/Project.toml
+++ b/Project.toml
@@ -9,10 +9,13 @@ Zlib_jll = "83775a58-1f1d-513f-b197-d71354ab007a"
 
 [compat]
 Zlib_jll = "1.2.11"
-julia = "1.3.0"
+julia = "1.6.0"
 
 [extras]
+LibArchive_jll = "1e303b3e-d4db-56ce-88c4-91e52606a1a8"
+PyCall = "438e738f-606a-5dbb-bf0a-cddfbfd45ab0"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+p7zip_jll = "3f19e933-33d8-53b3-aaab-bd5110c3b7a0"
 
 [targets]
-test = ["Test"]
+test = ["LibArchive_jll", "PyCall", "Test", "p7zip_jll"]
diff --git a/test/external_unzippers.jl b/test/external_unzippers.jl
new file mode 100644
index 0000000..f95e513
--- /dev/null
+++ b/test/external_unzippers.jl
@@ -0,0 +1,84 @@
+# Used to test that zip files written by ZipFile.jl can be read by other programs.
+# This defines a vector of functions in `unzippers`
+# These functions take a zipfile path and a directory path and extract the zipfile into the directory
+using Test
+using ZipFile
+import p7zip_jll
+import LibArchive_jll
+import PyCall
+
+
+
+"""
+Extract the zip file at zippath into the directory dirpath
+Use p7zip
+"""
+function unzip_p7zip(zippath, dirpath)
+    # pipe output to devnull because p7zip is noisy
+    p7zip_jll.p7zip() do exe
+        run(pipeline(`$(exe) x -y -o$(dirpath) $(zippath)`, devnull))
+    end
+    nothing
+end
+
+"""
+Extract the zip file at zippath into the directory dirpath
+Use bsdtar from libarchive
+"""
+function unzip_bsdtar(zippath, dirpath)
+    LibArchive_jll.bsdtar() do exe
+        run(`$(exe) -x -f $(zippath) -C $(dirpath)`)
+    end
+    nothing
+end
+
+"""
+Extract the zip file at zippath into the directory dirpath
+Use zipfile.py from python standard library
+"""
+function unzip_python(zippath, dirpath)
+    zipfile = PyCall.pyimport("zipfile")
+    PyCall.@pywith zipfile.ZipFile(zippath) as f begin
+        isnothing(f.testzip()) || error(string(f.testzip()))
+        f.extractall(dirpath)
+    end
+    nothing
+end
+
+
+# This is modified to only check for `unzip` from 
+# https://github.com/samoconnor/InfoZIP.jl/blob/1247b24dd3183e00baa7890c1a2c7f6766c3d774/src/InfoZIP.jl#L6-L14
+function have_infozip()
+    try
+        occursin(r"^UnZip.*by Info-ZIP", read(`unzip`, String))
+    catch
+        return false
+    end
+end
+
+"""
+Extract the zip file at zippath into the directory dirpath
+Use unzip from the infamous builtin Info-ZIP
+"""
+function unzip_infozip(zippath, dirpath)
+    try
+        run(`unzip -qq $(zippath) -d $(dirpath)`)
+    catch
+        # unzip errors if the zip file is empty for some reason
+    end
+    nothing
+end
+
+
+unzippers = [
+    unzip_p7zip,
+    unzip_bsdtar,
+    unzip_python,
+]
+
+if have_infozip()
+    push!(unzippers, unzip_infozip)
+else
+    @info "system Info-ZIP unzip not found, skipping `unzip_infozip` tests"
+end
+
diff --git a/test/runtests.jl b/test/runtests.jl
index 5ce1221..189b45d 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -177,6 +177,37 @@ r = ZipFile.Reader(filename)
 close(r)
 close(dir)
 
+# This defines a vector of functions in `unzippers`
+# These functions take a zipfile path and a directory path
+# They extract the zipfile into the directory
+include("external_unzippers.jl") 
+
+@testset "Writer compat with $(unzipper)" for unzipper in unzippers
+    for filename in readdir(tmp)
+        endswith(filename, ".zip") || continue
+        zippath = joinpath(tmp, filename)
+        mktempdir() do tmpout
+            # Unzip into an output directory
+            unzipper(zippath, tmpout)
+            # Read zippath with ZipFile.Reader
+            # Check file names and data match
+            local dir = ZipFile.Reader(zippath)
+            for f in dir.files
+                local name = f.name
+                local extracted_path = joinpath(tmpout, name)
+                @test isfile(extracted_path)
+                @test read(f) == read(extracted_path)
+            end
+            # Check number of extracted files match
+            local total_files = sum(walkdir(tmpout)) do (root, dirs, files)
+                length(files)
+            end
+            @test length(dir.files) == total_files
+            close(dir)
+        end
+    end
+end
+
 
 if !Debug
     rm(tmp, recursive=true)