architecture — RedDB blog

May 2026 Engineering · 17 · 14 min One WAL, four data models: how cross-modality transactions actually work A deep dive into the shared write-ahead log that lets a document update, a vector insert, a KV write, and a blob commit land in the same transaction. Record layout, the fsync contention tradeoff, and the four mitigations we shipped before the tail latency became someone else's incident.
Engineering · 16 · 10 min Stop stitching Postgres, pgvector, S3, and Redis Every modern app you ship is four databases in a trenchcoat. Here is the bill — in failure surfaces, ops playbooks, and consistency models — that nobody costs out before signing.
Engineering · 14 · 7 min The tradeoffs we made to fit four engines in one Document, vector, KV and blob in the same transaction is not free. Here's the per-modality tuning surface we cut, the plugin story we sacrificed, and the cold-blob latency tail we accepted.
RAG · 12 · 8 min RAG without a second database When your vectors live on the same row as the document they describe, the entire CDC-and-backfill layer of a RAG pipeline disappears — and a class of stale-retrieval bugs goes with it.
Apr 2026 Engineering · 24 · 9 min Why 'best of breed' loses at small scale The ops cost of running four engines instead of one, measured in person-hours at team sizes of 2, 5, and 15 engineers. Multi-model isn't only a scale concern — it's a small-team unlock.
Engineering · 22 · 9 min When you don't need RedDB An honest list of workloads where Postgres + pgvector, SQLite, or a single-purpose store will serve you better than RedDB. If your shape is on this list, save yourself the migration.

RedDB Cloud

Join the private beta.

One-click managed deploy. Free during beta. Founding pricing locked at GA.

Request access →