playbook/antigravity-awesome-skills/skills/vercel-optimize/references/support-topics/fluid-compute-caveats.md

id	title	status	candidateKinds	frameworks	priority	citations	maxBriefChars
fluid-compute-caveats	Fluid compute caveats	active	platform_fluid_compute cold_start	*	80	https://vercel.com/docs/fluid-compute	900

Investigation Brief

Fluid compute is a project-level lever. Use it when the setting is off and metrics show cold-start or warm-instance reuse pressure. Fluid can handle multiple invocations in one function instance; avoid per-request state in module scope.

Evidence To Check

Check project facts, startTypeSplit, cold-vs-warm latency, and routes carrying the cold-start share. When enabling Fluid, audit module-state hazards Fluid surfaces (not creates): module-scoped mutable state, lazy singletons holding per-user data, globals keyed on per-request inputs.

Do Not Recommend When

Do not recommend enabling fluid compute when project facts say it is already on. Do not frame as a file-level code fix.

Verification

State project setting, cold-start rate or fallback slow-route signal, affected route concentration. If enabling, call out module-state audit as follow-up.