gatsbyjs/gatsby · error · Error

If you encounter this error, it's probably a Gatsby internal

Error message

If you encounter this error, it's probably a Gatsby internal bug. Please open an issue reporting us this.

What it means

The v2 jobs reducer's END_JOB_V2 case reads state.jobsV2.incomplete.get(jobContentDigest) and destructures `{ job }` from it; if no incomplete job exists for that digest, `job` is undefined and the reducer throws, telling the user this is almost certainly a Gatsby internal bug. The v2 API keys jobs by contentDigest, and END_JOB_V2 should always have a matching START_JOB_V2 predecessor in the same build.

Source

Thrown at packages/gatsby/src/redux/reducers/jobsv2.ts:64

    case `CREATE_JOB_V2`: {
      const { job } = action.payload

      state.incomplete.set(job.contentDigest, {
        job,
      } as IGatsbyIncompleteJobV2)

      return state
    }

    case `END_JOB_V2`: {
      const { jobContentDigest, result } = action.payload
      const { job } = state.incomplete.get(
        jobContentDigest
      ) as IGatsbyIncompleteJobV2

      if (!job) {
        throw new Error(
          `If you encounter this error, it's probably a Gatsby internal bug. Please open an issue reporting us this.`
        )
      }

      state.incomplete.delete(job.contentDigest)

      // inputPaths is used to make sure the job is not stale
      state.complete.set(job.contentDigest, {
        result,
        inputPaths: job.inputPaths,
      } as IGatsbyCompleteJobV2)

      return state
    }

    case `REMOVE_STALE_JOB_V2`: {
      const { contentDigest } = action.payload
      state.incomplete.delete(contentDigest)

View on GitHub (pinned to 8b06340921)

Solutions

Report the issue to Gatsby with a reproduction (the message explicitly asks for this).
Clear .cache and public and rebuild to reset the v2 job maps.
Update to the latest Gatsby patch release in case it is a fixed internal bug.
If you maintain a plugin calling internal v2 job actions directly, ensure END_JOB_V2 only fires after a successful START_JOB_V2 with the same digest.

Defensive patterns

Strategy: try-catch

Try / catch

// This signals a Gatsby internal bug; surface and reset rather than swallow.
try {
  // ... v2 job lifecycle ...
} catch (e) {
  if (/probably a Gatsby internal bug/.test(e.message)) {
    report.error(e)
    // recommend gatsby clean + rebuild
  } else throw e
}

Prevention

Do not call internal v2 redux actions (START_JOB_V2 / END_JOB_V2) directly; use the public createJobV2 API.
Keep Gatsby updated to pick up internal fixes.
Run gatsby clean when job state looks inconsistent.

When it happens

Trigger: Dispatching END_JOB_V2 with a jobContentDigest that is absent from state.incomplete (never started, or already completed and deleted). The incomplete map is mutated (delete on completion), so a duplicate end also misses.

Common situations: Genuinely rare; indicates out-of-order dispatch, replayed actions after a partial cache, or a regression in the v2 job orchestration. End users essentially cannot cause this through normal plugin APIs - it is a guard for invariant violations inside Gatsby's job runner.

Related errors

AI-assisted analysis of gatsbyjs/gatsby@8b06340921 (2026-08-13). Data as JSON: /api/errors/6185c51c69181f51. Report an issue: GitHub.