Eric Allam
5ba8557a51
## Summary v3 (the engine that ran the SDK v3 era, internally `RunEngineVersion.V1`) is end-of-life. Following the removal of the v3 execution apps ([#4194](https://github.com/triggerdotdev/trigger.dev/pull/4194)) and the legacy dev websocket ([#4198](https://github.com/triggerdotdev/trigger.dev/pull/4198)), this removes the remaining v3 execution stack from the server. Clients still on v3 (an old SDK or CLI that has not upgraded) keep getting a clear "upgrade to v4" response. Triggers, batch triggers, reschedules, and deploys that resolve to v3 are rejected with a graceful 4xx pointing at the migration guide, never a 5xx, so a stale client cannot affect server health. Self-hosted instances still running v3 should stay on the 4.5.x release line until they migrate. ## What is removed - The MarQS queue and its shared/dev queue consumers. - The v3 socket.io namespaces (coordinator, provider, shared-queue) and the v3 run lifecycle services (attempt, checkpoint, and batch-resume). - The graphile-worker background job system; all live jobs already run on `@trigger.dev/redis-worker`. - The `DEPRECATE_V3_ENABLED` flag: v3 is now rejected unconditionally, so the flag is gone. - Unused v3 exports from `@trigger.dev/core` (the `v3/zodNamespace` subpath and the legacy socket message catalogs) and the now-dead MarQS environment variables. ## What stays The v4 engine is untouched. The graceful v3 rejection boundary stays, `determineEngineVersion` still detects a v3 project so it can reject it, and the batch service plus batch-completion worker stay for current clients. Live queue concurrency limits and metrics now read from the v4 run engine instead of MarQS, and a brand-new dev environment now defaults to v4. ## Dependency cleanup Removes webapp dependencies left unused by this change: `seedrandom` and `semver` (only the removed v3 code used them) plus a set that was already dead, their orphaned `@types` packages, and two dead files. Adds a `knip:deps` script and a `knip.json` config so unused dependencies can be found the same way going forward.
Server Changes
This directory tracks changes to server-only components (webapp, supervisor, etc.) that are not captured by changesets. Changesets only track published npm packages — server changes would otherwise go undocumented.
When to add a file
Server-only PRs: If your PR only changes apps/webapp/, apps/supervisor/, or other server components (and does NOT change anything in packages/), add a .server-changes/ file.
Mixed PRs (both packages and server): Just add a changeset as usual. No .server-changes/ file needed — the changeset covers it.
Package-only PRs: Just add a changeset as usual.
File format
Create a markdown file with a descriptive name:
.server-changes/fix-batch-queue-stalls.md
With this format:
---
area: webapp
type: fix
---
Speed up batch queue processing by removing stalls and fixing retry race
Fields
- area (required):
webapp|supervisor - type (required):
feature|fix|improvement|breaking
Description
The body text (below the frontmatter) is a one-line description of the change. Keep it concise — it will appear in release notes.
Writing guidance
These entries are public-facing - they ship verbatim in user-visible release notes. A few rules to keep them clean:
- Write for the user, not the reviewer. Lead with what the user notices or has to do. If a reader who doesn't know the codebase can't tell what changed for them, rewrite it.
- One sentence is usually enough. The body is the bullet in the changelog. If you need a paragraph, you're probably describing the implementation rather than the change.
- Describe behavior, not implementation. Skip internal scopes, middleware names, library specifics, framework internals. Users care about what's different for them, not how it's wired.
- Never name internal tools or infra. Observability stacks, internal services, infra components, monitoring backends, CI surfaces, AWS specifics - none of these belong in user-facing notes.
Before / after:
- ❌ "The image verification step now parses the manifest's layer media types and returns a new result the finalizer rejects." (describes the wiring; a user can't act on it)
- ✅ "Deploying with an outdated CLI could produce an image that fails to start on every run. These deploys are now stopped before going live, with a message asking you to upgrade the CLI and re-deploy." (what the user sees and does)
Lifecycle
- Engineer adds a
.server-changes/file in their PR - Files accumulate on
mainas PRs merge - The changeset release PR includes these in its summary
- After the release merges, CI cleans up the consumed files
Examples
New feature:
---
area: webapp
type: feature
---
TRQL query language and the Query page
Bug fix:
---
area: webapp
type: fix
---
Fix schedule limit counting for orgs with custom limits
Improvement:
---
area: webapp
type: improvement
---
Use the replica for API auth queries to reduce primary load