fix(build): recompute a stale package snapshot, not just a missing one #190
2026-08-31
fix(build): recompute a stale package snapshot, not just a missing one
The guard asked only whether the snapshot files exist. They describe S3 and CRAN state at the moment they were written, and the cache volume is per-agent, so an agent that ran an earlier pipeline keeps serving that pipeline's answer indefinitely. arm64/alpine324 reported '0 remaining' for both 4.4 and 4.6 from a snapshot listing 43 r-minor-sensitive packages, while the install-deps step of the same pipeline had just computed 6871 on another agent. Both numbers appear in one log: line 49 says 6871, line 99 says 43. That is why the slot looked finished in minutes while its own index step dropped 2407 and 2436 packages as missing. Keyed on the pipeline when the CI exposes an identifier, so a new pipeline recomputes once per agent and its shards share the result; otherwise an age check with a two hour default. Verified across five cases: missing, same pipeline, new pipeline, recent without a CI variable, and aged out.