Fix read-after-write race in the web cache#240
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DeployexWeb.Cache.set/2 was an asynchronous GenServer.cast while get/1 reads the ETS table directly, so a get right after a set could observe the previous value. This surfaced as a flaky UiSettingsTest failure where the setup wrote the cache and the test read a stale entry. The write is now a synchronous GenServer.call, guaranteeing that any subsequent read observes it. Risk assessment: - Impact: UI settings writes (nav menu toggle) become synchronous. The caller now waits for the cache GenServer, which only does an ETS insert, so the latency is negligible. - Blast radius: DeployexWeb.Cache only; the single caller today is Cache.UiSettings. - Regression risk: very low. A call can time out if the cache server is overloaded, but it handles rare, tiny writes. - Rollback: revert this commit.
thiagoesteves
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Jul 8, 2026
…guide (#244) * Update changelog with 0.9.5 entries and document changelog maintenance Add the missing 0.9.5 entries for the merged PRs: #239, #240, #241 and #242 as bug fixes, and #237 (CloudWatch log group retention) as an enhancement. Document the changelog maintenance rules in AGENTS.md so agents know how to add entries, and remove the outdated note that said the changelog must not be edited manually. Risk assessment: - Impact: documentation only, no runtime behavior changes. - Blast radius: CHANGELOG.md and AGENTS.md. - Regression risk: none, docs-only diff. - Rollback: revert this commit. * Updated changelog
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DeployexWeb.Cache.set/2 was an asynchronous GenServer.cast while get/1 reads the ETS table directly, so a get right after a set could observe the previous value. This surfaced as a flaky UiSettingsTest failure where the setup wrote the cache and the test read a stale entry.
The write is now a synchronous GenServer.call, guaranteeing that any subsequent read observes it.
Risk assessment:
Co-Authored-By: Claude Fable 5 noreply@anthropic.com