feat!: split trace/contrib integrations into individual Go modules

[Abhijeet Prasad (AbhiPrasad)]

AI Summary

Split every trace/contrib integration into its own Go module (mirroring the architecture of DataDog/dd-trace-go) and overhaul the release pipeline to correctly handle an arbitrary number of nested modules.

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⚠️ Breaking Change: Integration imports

Integration provider SDKs are no longer transitive dependencies of the root module. Users must now explicitly depend on the specific integration modules they use.

Before

go get github.com/braintrustdata/braintrust-sdk-go

This single dependency transitively pulled in every integration provider SDK
(OpenAI, Anthropic, Google GenAI, etc.), even if you only used one.

After

# Root SDK (required)
go get github.com/braintrustdata/braintrust-sdk-go

# Add only the integrations you need
go get github.com/braintrustdata/braintrust-sdk-go/trace/contrib/openai
go get github.com/braintrustdata/braintrust-sdk-go/trace/contrib/anthropic
go get github.com/braintrustdata/braintrust-sdk-go/trace/contrib/genai
# ... etc.

If you want every integration at once (previous behavior), use the trace/contrib/all convenience module:

go get github.com/braintrustdata/braintrust-sdk-go/trace/contrib/all

Available integration modules

Module path	Provider
trace/contrib/openai	OpenAI (official Go SDK)
trace/contrib/anthropic	Anthropic
trace/contrib/genai	Google GenAI
trace/contrib/genkit	Firebase Genkit
trace/contrib/adk	Google ADK
trace/contrib/langchaingo	LangChain Go
trace/contrib/cloudwego/eino	CloudWeGo Eino
trace/contrib/github.com/sashabaranov/go-openai	sashabaranov/go-openai
trace/contrib/all	Meta-module (imports all of the above)

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New release process

Releases are now fully automated via GitHub Actions across three stages.
Full details in docs/PUBLISHING.md.

How it works

1. Prepare (manual trigger) — run the "Prepare Release" workflow with a
   version like v1.2.3. It creates a release/vX.Y.Z branch, pins the root
   module version and any nested-module interdependencies in every nested
   go.mod, and opens a PR.

2. Review & merge — the PR should only contain go.mod / go.sum
   version-pin updates. Merge through the normal protected-branch process.

3. Tag & publish (automatic) — merging triggers:

   • Tag Release — runs make ci on the merge commit, then creates tags
     for the root module (vX.Y.Z) and every nested module
     (<module-path>/vX.Y.Z).
   • Release — triggered by the root tag push, runs goreleaser and warms
     the Go module proxy cache.

Key improvements in the release pipeline

• Dependency-ordered tagging — a new internal Go tool (internal/nestedmodules)
  topologically sorts nested modules so that a module is always tagged after any
  other nested modules it depends on (e.g., trace/contrib/all depends on
  trace/contrib/openai, so openai is tagged first).
• Atomic tag push — all tags are pushed in a single git push --atomic,
  ensuring the publish workflow only fires after every tag exists on the remote.
  This prevents partial-release races.
• Merge-commit checkout — the Tag Release workflow now checks out the actual
  merge commit SHA (github.event.pull_request.merge_commit_sha) instead of
  main, avoiding a race where a later commit lands between merge and tag.
• Resilient proxy indexing — Go proxy cache warming now retries up to 10
  times with backoff instead of a fire-and-forget curl.

Adding a new integration

1. Add the module path to scripts/nested_modules.txt.
2. Add a replace directive in its go.mod pointing to the repo root.
3. The check-nested-modules Make target will catch any manifest drift.

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[Matt Perpick (clutchski)]

is this fast and quiet :) pre-commit hooks must be fast and silent if everything is fine

[Matt Perpick (clutchski)]

I think i support this. we should also verify that we now depend on the lowest version of things we possibly can.

[Matt Perpick (clutchski)]

Note! This should only be silent if everything is fine. It can print output if it fails see verify-fmt

[Abhijeet Prasad (AbhiPrasad)]

okay this should be ready for review and merge now! Cleaned up a bunch from the initial implementation. I've also updated all the integrations to be pinned to the minimum possible version that needs to be supported.

[Matt Perpick (clutchski)]

Approved. Just make sure it's a clear upgrade path for users.