Infrastructure Decisions · judgement tool

Do I need Redis?

Rate limiting, shared sessions, pub/sub and caching are the real triggers — and your existing Postgres may already cover several. Get a verdict with each factor tagged official fact / calculation / StackSays rule / estimate.

A judgement tool, not a tool ranking · thresholds are StackSays rules, not industry standards · official facts verified 2026-07-17 · share the URL to share your answers

How to read this: every factor below is tagged by where it comes from — official fact official/documented · calculation math on your inputs · StackSays rule our decision logic · StackSays estimate our judgement. The verdict cut-points are StackSays rules, not an industry threshold — there is no universal traffic number for these decisions.

Your situation

The recommendation updates as you answer. Share the URL to share it.

Want a cachehot reads / expensive responsesNeed rate limitingthrottle requests per user/IPShared session / token storestate shared across serverless instancesPub/sub or presencerealtime fan-out, online counts, leaderboardsSimple job queuelightweight background jobsAlready run Postgreswhich can cover several of these

Recommendation

Not yet

Based on the factors you set — 0 pushing toward adopting, 1 against.

Why it might be premature

-14 Postgres can cover it — Your existing Postgres can cover caching, sessions and light queues (SKIP LOCKED, unlogged tables) — adding Redis may be premature (our judgement)StackSays estimate

When to reassess

Add Redis when a specific need above (rate limiting, cross-instance state, pub/sub) appears that Postgres serves awkwardly — not on a traffic number.

Minimal implementation

A hosted serverless Redis (e.g. Upstash) with pay-per-request billing avoids running infrastructure. Use it for the one need that triggered this, not as a default.

Risk of not doing it

Reinventing rate limiting / sessions on the DB with more contention; harder realtime features.

Cost & complexity once adopted

Another datastore to operate and pay for. Serverless Redis lowers the ops cost; the design cost is deciding what belongs in it vs Postgres.

This is a judgement tool, not a leaderboard. The StackSays rule and StackSays estimate factors are StackSays logic and opinion; the official fact factors link to official sources below. No industry-standard threshold is implied — the answer is driven by the conditions you set.

Official facts cited

Source	Verified
Redis use cases (official)	2026-07-17
Postgres SKIP LOCKED (official — queue-in-Postgres)	2026-07-17

Only the factors tagged “official fact” rest on these sources; rules and estimates are StackSays logic and are labeled as such.

Next decision

When should I add caching? →Do I need a message queue? →