fix: unwedge terraform-apply on RDS engine version drift - #261
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The aws module's `terraform-apply` has been failing on every merge:
InvalidParameterCombination: Cannot upgrade postgres from 17.9 to 17.6
main.tf pinned engine_version = "17.6", but RDS auto-applied a minor upgrade to
17.9 on the live instance. Terraform then tried to "downgrade" it, AWS rejected
it, and the whole aws-module apply aborted — which is why #256's Amplify changes
(SSR service role, NEXT_PUBLIC_API_BASE_URL) never actually applied.
Set engine_version to the live 17.9 and disable auto_minor_version_upgrade so
the version can't drift above the pin again; version bumps are now intentional.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
nourshoreibah
marked this pull request as ready for review
June 30, 2026 23:39
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Why
terraform-applyfor theawsmodule has been failing on every merge to main (e.g. the #256 Amplify run):main.tfpinnedengine_version = "17.6", but RDS auto-applied a minor upgrade to 17.9 on the live instance. Terraform then plans a "downgrade" 17.9 → 17.6, AWS rejects it, and the entire aws-module apply aborts. That's why #256's Amplify changes (SSRiam_service_role_arn,NEXT_PUBLIC_API_BASE_URL) never landed — the apply died on RDS before reaching the Amplify update.What
engine_version = "17.9"— match the live instance, stop the downgrade attempt.auto_minor_version_upgrade = false— keep the version from drifting above the pin again, so apply stays green. Version bumps become an intentional edit-then-apply (tradeoff: minor patches are no longer automatic).Effect
Once merged,
terraform-applyshould succeed and finally apply the pending Amplify SSR config from #256. The Amplify app (dbcy90q4o31f7) still shows the default "Welcome" placeholder — after this + that apply, a push tomainshould trigger the first real SSR build.Verification
terraform fmtclean.terraform-planon this PR — confirm it shows only the RDS in-place update (engine_version17.6→17.9 metadata +auto_minor_version_upgradefalse) and no destroy.🤖 Generated with Claude Code