start here. scale forever.
Four coasters. Four databases. The ones you'll actually use — and when to reach for each.
The set
Coaster 1 — Postgres · "The default." Joins, ACID, JSONB, pgvector for AI embeddings, full-text search. Start here.
Coaster 2 — Redis · "The cache." GET/SET in sub-millisecond, TTL, pub/sub, session state, rate limits. When Postgres is too slow.
Coaster 3 — MongoDB · "Flex schema." BSON documents, find(), $lookup, sharding, aggregation pipelines.
Coaster 4 — pgvector · "AI-native." Embeddings, cosine distance, HNSW index, RAG retrieval. The one you'll need in 2026.
Every backend starts with "which database?"
Now the answer is on your desk.
The details
4 glossy hardboard coasters, 3.75" × 3.75". Cork-backed, heat resistant. Dye sublimation print.
Pairs with
Backend Architecture Map desk mat.
Part of the quux coaster collection. quux.shop