diff --git a/.github/workflows/github-actions-check-pydantic.yaml b/.github/workflows/check-python-code.yaml
similarity index 81%
rename from .github/workflows/github-actions-check-pydantic.yaml
rename to .github/workflows/check-python-code.yaml
index 406d77f76..97d37eb4b 100644
--- a/.github/workflows/github-actions-check-pydantic.yaml
+++ b/.github/workflows/check-python-code.yaml
@@ -1,4 +1,4 @@
-name: Check Pydantic models
+name: Check Python package code
 
 on:
   pull_request_target:
@@ -6,6 +6,12 @@ on:
       - 'packages/**'
       - 'pyproject.toml'
       - 'uv.lock'
+  push:
+    branches: [main, dev]
+    paths:
+      - 'packages/**'
+      - 'pyproject.toml'
+      - 'uv.lock'
 
 jobs:
   check:
diff --git a/.github/workflows/check-python-package-versions.yaml b/.github/workflows/check-python-package-versions.yaml
new file mode 100644
index 000000000..4b0fdf41e
--- /dev/null
+++ b/.github/workflows/check-python-package-versions.yaml
@@ -0,0 +1,15 @@
+name: Check Python package version numbers
+
+on:
+  pull_request_target:
+    paths:
+      - '**/pyproject.toml'
+      - 'packages/**/__about__.py'
+
+jobs:
+  check:
+    if: github.event.pull_request.head.repo.full_name == github.repository
+    uses: ./.github/workflows/reusable/check-python-package-versions.yaml'
+    with:
+      before_commit: ${{ github.event.pull_request.base.sha }}
+      after_commit: ${{ github.event.pull_request.head.sha }}
diff --git a/.github/workflows/github-actions-copy-latest-docs-to-staging.yaml b/.github/workflows/copy-latest-docs-to-staging.yaml
similarity index 100%
rename from .github/workflows/github-actions-copy-latest-docs-to-staging.yaml
rename to .github/workflows/copy-latest-docs-to-staging.yaml
diff --git a/.github/workflows/github-actions-copy-pr-docs-to-staging.yaml b/.github/workflows/copy-pr-docs-to-staging.yaml
similarity index 100%
rename from .github/workflows/github-actions-copy-pr-docs-to-staging.yaml
rename to .github/workflows/copy-pr-docs-to-staging.yaml
diff --git a/.github/workflows/github-actions-enforce-change-type-label.yaml b/.github/workflows/enforce-change-type-label.yaml
similarity index 100%
rename from .github/workflows/github-actions-enforce-change-type-label.yaml
rename to .github/workflows/enforce-change-type-label.yaml
diff --git a/.github/workflows/github-actions-publish-docs-gh-pages.yaml b/.github/workflows/publish-docs-gh-pages.yaml
similarity index 100%
rename from .github/workflows/github-actions-publish-docs-gh-pages.yaml
rename to .github/workflows/publish-docs-gh-pages.yaml
diff --git a/.github/workflows/reusable/check-python-package-versions.yaml b/.github/workflows/reusable/check-python-package-versions.yaml
new file mode 100644
index 000000000..7c88177b2
--- /dev/null
+++ b/.github/workflows/reusable/check-python-package-versions.yaml
@@ -0,0 +1,84 @@
+name: Check Python package versions
+
+on:
+  workflow_call:
+    inputs:
+      before_commit:
+        description: >-
+            The base Git commit to compare against, i.e., the base of the PR or the previous commit
+            in a push.
+        type: string
+        required: true
+      after_commit:
+        description: >-
+            The Git commit representing the head of the change to be checked, i.e. the head of the
+            PR or the latest commit in a push.
+        type: string
+        required: true
+
+jobs:
+  get-index-url:
+    uses: ./.github/workflows/reusable/get-code-artifact-index-url.yaml
+
+  check-python-package-versions:
+    needs: get-index-url
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install jq
+        run: sudo apt-get update && sudo apt-get install -y jq
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v4
+        with:
+          version: "latest"
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.10"
+
+      - name: Check out code before change
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.before_commit }}
+
+      - name: Capture package versions before change
+        run: uv run python scripts/package-versions.py collect > /tmp/package-versions-before.json
+
+      - name: Check out code after change
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.after_commit }}
+
+      - name: Capture package versions after change
+        run: uv run python scripts/package-versions.py collect > /tmp/package-versions-after.json
+
+      - name: Compare package versions before and after change
+        run: |
+          uv run python scripts/package-versions.py compare \
+            /tmp/package-versions-before.json \
+            /tmp/package-versions-after.json \
+            >/tmp/package-version-diff.json
+
+      - name: Print changed versions
+        run: cat /tmp/package-version-diff.json
+
+      - name: Fail if any of the new versions already exist in the repo
+        run: |
+          jq -c '.[]' /tmp/package-version-diff.json | while read -r entry; do
+            package=$(echo "$entry" | jq -r '.package')
+            after=$(echo "$entry" | jq -r '.after')
+            exit_code=0
+            output=$(uv run pip download "${package}==${after}" --index-url "${{ needs.get-index-url.outputs.index_url }}simple/" --no-deps -d /tmp --quiet 2>&1) | exit_code=$?
+            if [[ $exit_code -eq 0 || (
+              "${output,,}" != *"could not find a version"* &&
+              "${output,,}" != *"no matching distributions"*
+            ) ]]; then
+              echo "Package ${package} version ${after} already exists in the repository. Failing the workflow."
+              echo "    pip exit code: ${exit_code}."
+              echo "    pip stderr: ${output}."
+              exit 1
+            else
+              echo "Package ${package} version ${after} is new, as expected. Continuing."
+            fi
+          done
diff --git a/.github/workflows/reusable/get-code-artifact-index-url.yaml b/.github/workflows/reusable/get-code-artifact-index-url.yaml
new file mode 100644
index 000000000..e8dec13f0
--- /dev/null
+++ b/.github/workflows/reusable/get-code-artifact-index-url.yaml
@@ -0,0 +1,57 @@
+name: Get CodeArtifact Python package index URL
+
+on:
+  workflow_call:
+    inputs:
+      account_id:
+        description: The AWS account ID that owns the CodeArtifact domain
+        type: string
+        required: false
+        default: 505071440022
+      aws_region:
+        description: The AWS region where the CodeArtifact repository is hosted
+        type: string
+        required: false
+        default: us-west-2
+      role_name:
+        description: The name of the IAM role to assume for accessing CodeArtifact
+        type: string
+        required: false
+        default: GithubActions_Schema_CodeArtifact_ReadOnly
+      domain:
+        description: The CodeArtifact domain name
+        type: string
+        required: false
+        default: overture-pypi
+      repository:
+        description: The CodeArtifact repository name
+        type: string
+        required: false
+        default: overture
+    outputs:
+      index_url:
+        description: The CodeArtifact Python index URL
+        value: ${{ jobs.get-code-artifact-index-url.outputs.index_url }}
+
+jobs:
+  get-code-artifact-index-url:
+    runs-on: ubuntu-latest
+    outputs:
+      index_url: ${{ steps.get-code-artifact-index-url.outputs.index_url }}
+    steps:
+      - name: Configure AWS credentials
+        uses: aws-actions/configure-aws-credentials@v4
+        with:
+          aws-region: ${{ inputs.aws_region }}
+          role-to-assume: arn:aws:iam::${{ inputs.account_id }}:role/${{ inputs.role_name }}
+          role-session-name: GitHubActions_${{github.workflow}}_${{github.job}}_${{github.run_id}}
+
+      - name: Get CodeArtifact authorization token
+        id: get-code-artifact-auth-token
+        run: |
+          AUTH_TOKEN=$(aws codeartifact get-authorization-token \
+            --domain ${{ inputs.domain }} \
+            --domain-owner ${{ inputs.account_id }} \
+            --query authorizationToken \
+            --output text)
+          echo "https://aws:${AUTH_TOKEN}@$${{ inputs.domain }}-${{ inputs.account_id }}.d.codeartifact.${{ inputs.aws_region }}.amazonaws.com/simple/" >> $GITHUB_OUTPUT
diff --git a/.github/workflows/scripts/package-versions.py b/.github/workflows/scripts/package-versions.py
new file mode 100755
index 000000000..4507d2672
--- /dev/null
+++ b/.github/workflows/scripts/package-versions.py
@@ -0,0 +1,134 @@
+#!/usr/bin/env python3
+
+from importlib import metadata
+from pathlib import Path
+import json
+import sys
+
+
+def collect():
+    """
+    Collect Python package versions and print them as a JSON array.
+
+    Form of the JSON array:
+
+        [ {"package": "p1", "version": "v1"}, {"package": "p2", "version": "v2"}, ... ]
+    """
+    packages_dir = Path("packages")
+
+    packages = sorted(
+        d.name
+        for d in packages_dir.iterdir()
+        if d.is_dir() and d.name.startswith("overture-schema")
+    )
+
+    package_versions = [
+        {"package": p, "version": metadata.version(p.replace("-", "."))}
+        for p in packages
+    ]
+
+    print(json.dumps(package_versions, indent=2))
+
+
+def compare(before_file: str, after_file: str):
+    """
+    Compare two JSON files containing package versions and print the packages that have a version
+    number change as a JSON array.
+
+    Form of the JSON array:
+
+        [ {"package": "p1", "before": "v1", "after": "v2"}, ... ]
+
+    Note that `before` will be `null` if the package did not exist in the "before" file, and `after`
+    will be `null` if the package did not exist in the "after" file.
+    """
+    before_array = load(before_file)
+    after_array = load(after_file)
+
+    before_dict = {item["package"]: item["version"] for item in before_array}
+    after_dict = {item["package"]: item["version"] for item in after_array}
+
+    combined_keys = sorted(list(set(before_dict.keys()) | set(after_dict.keys())))
+
+    changed_packages = []
+    for package in combined_keys:
+        before_version = before_dict.get(package)
+        after_version = after_dict.get(package)
+        if before_version != after_version:
+            changed_packages.append(
+                {
+                    "package": package,
+                    "before": before_version,
+                    "after": after_version,
+                }
+            )
+
+    print(json.dumps(changed_packages, indent=2))
+
+
+def load(file_path: str) -> list[dict[str, str]]:
+    path = Path(file_path)
+    if not path.exists():
+        print(f"File not found: {file_path}")
+        sys.exit(1)
+
+    with path.open() as f:
+        value = json.load(f)
+
+    if not isinstance(value, list):
+        print(
+            f"File {file_path} contains unexpected root value: expected a `list` but got value {repr(value)} of type `{type(value).__name__}`"
+        )
+        sys.exit(1)
+
+    for i, item in enumerate(value):
+        if not isinstance(item, dict):
+            print(
+                f"File {file_path} contains unexpected item at index {i}: expected `dict` but got value {repr(item)} of type `{type(item).__name__}`"
+            )
+            sys.exit(1)
+        elif sorted(item.keys()) != ["package", "version"]:
+            print(
+                f"File {file_path} contains unexpected item at index {i}: expected keys `['package', 'version']` but got keys {sorted(item.keys())}"
+            )
+            sys.exit(1)
+        elif not isinstance(item["package"], str):
+            print(
+                f"File {file_path} contains unexpected item at index {i}: expected `package` to be of type `str` but got value {repr(item['package'])} of type `{type(item['package']).__name__}`"
+            )
+            sys.exit(1)
+        elif not isinstance(item["version"], str):
+            print(
+                f"File {file_path} contains unexpected item at index {i}: expected `version` to be of type `str` but got value {repr(item['version'])} of type `{type(item['version']).__name__}`"
+            )
+            sys.exit(1)
+
+    return value
+
+
+def usage():
+    print("Usage:")
+    print(f"  ./{sys.argv[0]} collect")
+    print(f"  ./{sys.argv[0]} compare BEFORE_FILE AFTER_FILE")
+    sys.exit(1)
+
+
+def main():
+    if len(sys.argv) < 2:
+        usage()
+
+    cmd = sys.argv[1]
+
+    if cmd == "collect":
+        collect()
+    elif cmd == "compare":
+        if len(sys.argv) != 4:
+            usage()
+        compare(sys.argv[2], sys.argv[3])
+    else:
+        print(f"Unknown command: {cmd}")
+        usage()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/.github/workflows/github-actions-test-schema.yaml b/.github/workflows/test-schema.yaml
similarity index 100%
rename from .github/workflows/github-actions-test-schema.yaml
rename to .github/workflows/test-schema.yaml