- MAY 2026
Chunking inside the engine: when the DB owns segmentation
Most RAG stacks chunk in Python glue between Postgres and a vector store. The result is a second pipeline that drifts. This post walks through what it looks like when chunking is a declarative rule attached to a column, reranking is a query operator, and the engine — not the application — owns segmentation.
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Hybrid search done right: lexical, vector, and filter in one plan
A walk through the RedDB query planner fusing BM25, vector similarity, and a structured filter into a single execution plan — with EXPLAIN output, the cost model behind it, and what happens on the edge cases that trip up naive two-stage rerankers.
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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.
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Hello from inside the engine
A first note on what we're building and why a multi-model engine matters in 2026.
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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.
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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.
- APR 2026
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.
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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.