PRO

Effect Quorum Reads with Read Repair

Eventual consistency with an actual mechanism: N replicas, write to W, read from R, R + W > N, so every read set overlaps every write set and the newest version is always among the answers; the reader takes the highest version, so a partitioned replica's stale copy cannot win a quorum read. Divergence heals instead of lingering: a read that observes disagreeing versions writes the winner back to the stale replicas on a detached fiber (read repair off the read path), replicas reject version regressions so repair can never move a copy backward, and losing quorum is a typed QuorumUnreachable refusal rather than a wrong answer. Pinned to effect 4.0.0-beta.98.

Install
npx shadcn@latest add https://ui.aryank.space/r/effect-quorum-read-repair.json

Installs from ui.aryank.space. To add it by hand, copy the files in Files below, or register the @compronents namespace via the docs.

Visualization
read
r3 (was partitioned)
Effect<Versioned | undefined, ReplicaDown>
r1
client
unknown
r3.get(key) // whichever replica you hit is the truth you get

The write landed on r1 and r2 while r3 was partitioned. r3 is back now, still holding yesterday, and this read happened to route there. The client gets theme=light, acts on it, and overwrites the user's change: staleness became a lost update because one copy was trusted alone.

Files

Dependencies