diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 000000000..e0a1c6a47
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,16 @@
+version: 2
+updates:
+  - package-ecosystem: pip
+    directory: "/.github/workflows"
+    schedule:
+      interval: daily
+      time: "12:00"
+      timezone: "UTC"
+    reviewers: [meltano-engineering]
+    labels: [deps]
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: weekly
+    reviewers: [meltano-engineering]
+    labels: [deps]
diff --git a/.github/workflows/constraints.txt b/.github/workflows/constraints.txt
new file mode 100644
index 000000000..73244c442
--- /dev/null
+++ b/.github/workflows/constraints.txt
@@ -0,0 +1,3 @@
+pip==22.1.1
+poetry==1.1.13
+virtualenv==20.14.1
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 000000000..e44c23ee9
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,112 @@
+name: Test
+
+on:
+  pull_request: {}
+  push:
+    branches: [main]
+  workflow_dispatch:
+    inputs: {}
+
+jobs:
+  tests:
+    name: Test on ${{ matrix.python-version }} (${{ matrix.tox-env }}${{ matrix.external && ', external' || '' }}) / ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    continue-on-error: ${{ matrix.external || false }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+        - { tox-env: py, python-version: "3.7", os: "ubuntu-latest" }
+        - { tox-env: py, python-version: "3.8", os: "ubuntu-latest" }
+        - { tox-env: py, python-version: "3.9", os: "ubuntu-latest" }
+        - { tox-env: py, python-version: "3.10", os: "ubuntu-latest" }
+        #TODO: resolve by mapping CI vars to creds: 
+        # https://github.com/meltano/sdk/issues/683
+        # - { tox-env: py, python-version: "3.10", os: "ubuntu-latest", external: true }
+        - { tox-env: doctest, python-version: "3.10", os: "ubuntu-latest" }
+        - { tox-env: lint, python-version: "3.8", os: "ubuntu-latest" }
+
+    steps:
+    - name: Check out the repository
+      uses: actions/checkout@v3.0.2
+
+    - name: Install Poetry
+      env:
+        PIP_CONSTRAINT: .github/workflows/constraints.txt
+      run: |
+        pipx install poetry
+        poetry --version
+
+    - name: Setup Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v3.1.2
+      with:
+        python-version: ${{ matrix.python-version }}
+        architecture: x64
+        cache: 'poetry'
+
+    - name: Upgrade pip
+      env:
+        PIP_CONSTRAINT: .github/workflows/constraints.txt
+      run: |
+        pip install pip
+        pip --version
+
+    - name: Install Dependencies
+      run: |
+        poetry env use "${{ matrix.python-version }}"
+        poetry install
+
+    - name: Run tox
+      run: |
+        poetry run tox -e ${{ matrix.tox-env }} --${{ matrix.external && ' -m "external"' || '' }}${{ matrix.doctest && ' --doctest-modules singer_sdk' }}
+
+    - name: Upload coverage data
+      if: always() && (matrix.tox-env == 'py')
+      uses: actions/upload-artifact@v3.1.0
+      with:
+        name: coverage-data
+        path: ".coverage.*"
+
+  coverage:
+    runs-on: ubuntu-latest
+    needs: tests
+    steps:
+    - name: Check out the repository
+      uses: actions/checkout@v3.0.2
+
+    - name: Install Poetry
+      run: |
+        pipx install --pip-args=--constraint=.github/workflows/constraints.txt poetry
+        poetry --version
+
+    - name: Set up Python
+      uses: actions/setup-python@v3.1.2
+      with:
+        python-version: '3.10'
+        cache: 'poetry'
+
+    - name: Upgrade pip
+      run: |
+        pip install --constraint=.github/workflows/constraints.txt pip
+        pip --version
+
+    - name: Download coverage data
+      uses: actions/download-artifact@v3.0.0
+      with:
+        name: coverage-data
+
+    - name: Install Dependencies
+      run: |
+        poetry env use "3.10"
+        poetry install
+
+    - name: Combine coverage data and display human readable report
+      run: |
+        poetry run tox -e combine_coverage
+
+    - name: Create coverage report
+      run: |
+        poetry run tox -e coverage_xml
+
+    - name: Upload coverage report
+      uses: codecov/codecov-action@v3.1.0
diff --git a/poetry.lock b/poetry.lock
index e07bf818f..9679e74c9 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -155,18 +155,6 @@ python-versions = ">=3.6"
 colorama = {version = "*", markers = "platform_system == \"Windows\""}
 importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
 
-[[package]]
-name = "codecov"
-version = "2.1.12"
-description = "Hosted coverage reports for GitHub, Bitbucket and Gitlab"
-category = "dev"
-optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-
-[package.dependencies]
-coverage = "*"
-requests = ">=2.7.9"
-
 [[package]]
 name = "colorama"
 version = "0.4.4"
@@ -195,11 +183,14 @@ six = ">=1.10"
 
 [[package]]
 name = "coverage"
-version = "6.2"
+version = "6.4"
 description = "Code coverage measurement for Python"
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
+
+[package.dependencies]
+tomli = {version = "*", optional = true, markers = "python_version < \"3.11\" and extra == \"toml\""}
 
 [package.extras]
 toml = ["tomli"]
@@ -1271,7 +1262,7 @@ docs = ["sphinx", "sphinx-rtd-theme", "sphinx-copybutton", "myst-parser"]
 [metadata]
 lock-version = "1.1"
 python-versions = "<3.11,>=3.7.1"
-content-hash = "395e4f269bcddfbbc4d001181884b7efa5ba15cfdbad49e0292332bfcc7aacfe"
+content-hash = "38c18624435cc7280369dba0dee6840489de217e59b3a2869b51557d1725d8be"
 
 [metadata.files]
 alabaster = [
@@ -1377,11 +1368,6 @@ click = [
     {file = "click-8.0.3-py3-none-any.whl", hash = "sha256:353f466495adaeb40b6b5f592f9f91cb22372351c84caeb068132442a4518ef3"},
     {file = "click-8.0.3.tar.gz", hash = "sha256:410e932b050f5eed773c4cda94de75971c89cdb3155a72a0831139a79e5ecb5b"},
 ]
-codecov = [
-    {file = "codecov-2.1.12-py2.py3-none-any.whl", hash = "sha256:585dc217dc3d8185198ceb402f85d5cb5dbfa0c5f350a5abcdf9e347776a5b47"},
-    {file = "codecov-2.1.12-py3.8.egg", hash = "sha256:782a8e5352f22593cbc5427a35320b99490eb24d9dcfa2155fd99d2b75cfb635"},
-    {file = "codecov-2.1.12.tar.gz", hash = "sha256:a0da46bb5025426da895af90938def8ee12d37fcbcbbbc15b6dc64cf7ebc51c1"},
-]
 colorama = [
     {file = "colorama-0.4.4-py2.py3-none-any.whl", hash = "sha256:9f47eda37229f68eee03b24b9748937c7dc3868f906e8ba69fbcbdd3bc5dc3e2"},
     {file = "colorama-0.4.4.tar.gz", hash = "sha256:5941b2b48a20143d2267e95b1c2a7603ce057ee39fd88e7329b0c292aa16869b"},
@@ -1391,53 +1377,47 @@ cookiecutter = [
     {file = "cookiecutter-1.7.3.tar.gz", hash = "sha256:6b9a4d72882e243be077a7397d0f1f76fe66cf3df91f3115dbb5330e214fa457"},
 ]
 coverage = [
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 ]
 cryptography = [
     {file = "cryptography-3.4.8-cp36-abi3-macosx_10_10_x86_64.whl", hash = "sha256:a00cf305f07b26c351d8d4e1af84ad7501eca8a342dedf24a7acb0e7b7406e14"},
diff --git a/pyproject.toml b/pyproject.toml
index b9508407c..0c225a64d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -66,7 +66,6 @@ pyarrow = "^6.0.0"
 pandas = ">=1.2.0"
 numpy = ">=1.20.0"
 tox = "^3.23.1"
-codecov = "^2.1.11"
 freezegun = "^1.1.0"
 viztracer = "^0.14.0"
 flake8-annotations = "^2.6.2"
@@ -76,6 +75,7 @@ pyupgrade = "^2.29.1"
 requests-mock = "^1.9.3"
 sqlalchemy2-stubs = {version = "^0.0.2a19", allow-prereleases = true}
 types-requests = "^2.26.1"
+coverage = {extras = ["toml"], version = "^6.4"}
 
 [tool.black]
 exclude = ".*simpleeval.*"
@@ -87,7 +87,10 @@ src_paths = "singer_sdk"
 known_first_party = ["tests", "samples"]
 
 [tool.pytest.ini_options]
-addopts = '-vvv --ignore=singer_sdk/helpers/_simpleeval.py'
+addopts = '-vvv --ignore=singer_sdk/helpers/_simpleeval.py -m "not external"'
+markers = [
+    "external: Tests relying on external resources",
+]
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]
diff --git a/tests/conftest.py b/tests/conftest.py
index c7eedf770..eff8e32c5 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,9 +1,24 @@
 """Top level test fixtures."""
 
+from __future__ import annotations
+
 import os
+import pathlib
 import shutil
 
 import pytest
+from _pytest.config import Config
+
+
+def pytest_collection_modifyitems(config: Config, items: list[pytest.Item]):
+    rootdir = pathlib.Path(config.rootdir)
+
+    for item in items:
+        rel_path = pathlib.Path(item.fspath).relative_to(rootdir)
+
+        # Mark all tests under tests/external*/ as 'external'
+        if rel_path.parts[1].startswith("external"):
+            item.add_marker("external")
 
 
 @pytest.fixture(scope="class")
diff --git a/tox.ini b/tox.ini
index 950835817..3396271cc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,13 +14,15 @@ whitelist_externals = poetry
 commands_pre =
     poetry install --no-root
 commands =
-    poetry run coverage run -m pytest -x -v
-    poetry run coverage report --show-missing
-    poetry run codecov -e TOXENV
+    poetry run coverage run --parallel -m pytest -x -v {posargs}
 
 [testenv:test]
 # Use default py interpreter
 
+[testenv:doctest]
+commands =
+    poetry run pytest --doctest-modules {posargs:singer_sdk}
+
 [testenv:htmlcov]
 # Launch local web browser with previously-captured pytest coverage results
 whitelist_externals =
@@ -40,6 +42,15 @@ commands =
     poetry run flake8 singer_sdk tests samples
     poetry run mypy singer_sdk --exclude='tests'
 
+[testenv:combine_coverage]
+commands =
+    poetry run coverage combine
+    poetry run coverage report --show-missing
+
+[testenv:coverage_xml]
+commands =
+    poetry run coverage xml
+
 [flake8]
 ignore = W503, C901, ANN101
 max-line-length = 88
@@ -71,3 +82,4 @@ exclude_lines =
     raise NotImplementedError
     if __name__ == .__main__.:
     class .*\bProtocol\):
+fail_under = 85