Merge Upstream

Merge a specific upstream tag from DataDog/dd-trace-dotnet into the fork.

The user will provide the upstream tag to merge (e.g. v3.35.0). If not provided, determine it automatically:

1. •Find previously merged upstream versions:
   code

   .claude/skills/merge-upstream/find-previous-versions.sh
   

2. •Take the highest version found and increment the minor version (e.g. v3.34.0 → v3.35.0). Then check upstream for the latest patch of that minor version by listing remote tags:
   code

   git ls-remote --tags upstream 'refs/tags/v<major>.<next_minor>.*'
   

   Pick the highest patch version available (e.g. if v3.35.0 and v3.35.1 both exist, suggest v3.35.1). If no tags exist for that minor version, the tag doesn't exist yet — abort.
3. •Always confirm with the user before proceeding — show the previous version found and the proposed next version, and ask the user to confirm or provide a different tag.
4. •Ask the user which branch to base the merge on. Suggest main (recommended) but also offer the current branch (git branch --show-current) as an option. Use the chosen branch as <base> in step 3 below.

Fork context

The upstream project (dd-trace-dotnet) contains both a tracer and a profiler. Our fork only uses the profiler — the tracer is completely removed.

What we strip from upstream on every merge:

• •tracer/ — we don't use the Datadog tracer at all
• •profiler/src/Demos/, profiler/test/, profiler/src/Tools/ — upstream demo/test code we don't need
• •shared/test/ — upstream shared test code
• •.azure-pipelines/, .gitlab/ — upstream CI configs; we use GitHub Actions only
• •.github/ additions from upstream — we keep only our own pyroscope-specific workflows
• •.claude/ additions from upstream — we keep only our own claude configuration
• •.gitlab-ci.yml — upstream CI config; we use GitHub Actions only
• •docs/ — upstream documentation
• •shared/src/Datadog.Trace.ClrProfiler.Native — not used in our fork
• •build/cmake/FindSpdlog.cmake, shared/src/native-lib/spdlog, build/cmake/FindManagedLoader.cmake — we use git submodules for these instead

When resolving conflicts, keep this context in mind: if a conflict involves code paths related to the tracer, Azure CI, upstream demos, or upstream .github workflows, our side (deletion/absence) is correct.

IMPORTANT — git safety rules:

• •Never create PRs or push to the upstream DataDog repo. All PRs must target grafana/pyroscope-dotnet with --base main.
• •Never rebase or rewrite history. The only allowed destructive operations are --amend and --force-push on the merge commit of the branch created in step 2.
• •Only push to the kk/fork-update-* branch created for this merge — never to main.

The scripts bellow should be executed as is, as executable, without passing it to the bash. .claude/skills/merge-upstream/find-previous-versions.sh instead of bash .claude/skills/merge-upstream/find-previous-versions.sh

Steps

1. •

   Ensure upstream remote exists and fetch tags

   code

   git remote add upstream https://github.com/DataDog/dd-trace-dotnet.git
   

   Skip if already present. Fetch upstream tags:

   code

   git fetch upstream --tags
   

2. •

   Verify the target tag exists on the upstream remote

   code

   git ls-remote --tags upstream refs/tags/<tag>
   

   If the output is empty, the tag does not exist upstream — abort and inform the user. Do not rely on git tag -l as it only checks local refs which may be stale or wrong.

3. •

   Create a merge branch from the chosen base

   code

   git checkout -b kk/fork-update-<version> <base>
   

   If the branch already exists, delete it first and recreate:

   code

   git branch -D kk/fork-update-<version>
   git checkout -b kk/fork-update-<version> <base>
   

4. •

   Start the merge (no commit, no fast-forward)

   code

   git merge <tag> --no-commit --no-ff
   

5. •

   Remove directories we don't carry in the fork

   code

   git rm -rf tracer
   git rm -rf profiler/src/Demos/
   git rm -rf shared/src/Datadog.Trace.ClrProfiler.Native
   git rm -rf shared/test
   git rm -rf .azure-pipelines
   git rm -rf .gitlab
   git rm -rf docs
   git rm -rf profiler/test
   git rm -rf profiler/src/Tools
   git rm -f .gitlab-ci.yml
   

6. •

   Remove files we replace with git submodules

   code

   git rm -rf build/cmake/FindSpdlog.cmake
   git rm -rf shared/src/native-lib/spdlog
   git rm -rf build/cmake/FindManagedLoader.cmake
   

7. •

   Clean up files deleted by us but modified upstream (DU conflicts)

   code

   .claude/skills/merge-upstream/resolve-du-conflicts.sh
   

8. •

   Remove any upstream .github and .claude files that were added

   code

   .claude/skills/merge-upstream/remove-upstream-github.sh
   

9. •

   Resolve .github/CODEOWNERS — always keep the fork version If .github/CODEOWNERS has a conflict, always resolve it to the fork (grafana/pyroscope) version. The upstream CODEOWNERS contains DataDog-specific team ownership rules that are irrelevant to the fork. Check out our side and stage it:

   code

   git checkout --ours .github/CODEOWNERS
   git add .github/CODEOWNERS
   

10. •

    Resolve conflicts in CMake files first

• •List all conflicted files: git diff --name-only --diff-filter=U
• •Resolve CMake-related conflicts first (CMakeLists.txt, *.cmake files)
• •Then verify cmake configures successfully:
  code

  .claude/skills/merge-upstream/cmake_configure.sh
  

  Fix any cmake errors before proceeding to other conflicts.

1. •Resolve remaining conflicts

• •For version conflicts in binary/DLL/package references (e.g. NuGet versions, library versions, dependency pinning), always pick the higher version
• •Prefer our fork's changes for pyroscope-specific code
• •Ask the user when unsure which side to keep

1. •

   Verify the build (only the targets we use)

   Note: The build may take significant time (several minutes). Use a generous timeout (e.g. 600000ms). The script always removes the old build directory first.

   code

   .claude/skills/merge-upstream/build.sh
   

   Report any build errors and fix them before committing.

2. •

   Commit the merge

   • •git add -A && git commit with message: merge upstream <tag>
3. •

   Push and create a draft PR

   code

   git push -u origin kk/fork-update-<version>
   gh pr create --draft --repo grafana/pyroscope-dotnet --base <base> --label "upstream-merge" --title "merge upstream <tag>" --body "Merge upstream dd-trace-dotnet <tag> into the fork."
   

4. •

   Generate PR summary After the PR is created, invoke the merge-upstream-summary skill to generate a detailed summary and update the PR description.