Databases

SQLite by default, with no setup and no network. The connection string picks the backend, so moving to Postgres or Mongo is one command.

SQLite

Stored at ~/.claude-memory/memory.db. It comes from Node's builtin node:sqlite, so there is nothing to install and nothing compiles. Memory is partitioned by project path, so one database serves every repo you work in.

Switch database

claude-db use "postgres://user:pass@host:5432/memory"
claude-db use "mongodb+srv://user:pass@cluster.mongodb.net/memory"

use switches the backend and verifies it can be reached before saving. Install the driver you need first, either npm install pg or npm install mongodb, since neither ships by default. CLAUDE_DB_URL overrides the config file when you need a one-off.

Sync two databases

claude-db sync "postgres://user:pass@host:5432/memory"

A two-way merge, so a laptop and a desktop can each keep working offline and reconcile later. export and import cover the same ground as files when you would rather move a dump by hand.

MongoDB Atlas vector index

Atlas can index vector search instead of scanning brute-force, but Atlas indexes are not created by this tool. Add one by hand on the observations collection:

{
  "name": "memory_vector",
  "type": "vectorSearch",
  "fields": [
    { "type": "vector", "path": "embedding", "numDimensions": 256, "similarity": "cosine" },
    { "type": "filter", "path": "project" },
    { "type": "filter", "path": "kind" },
    { "type": "filter", "path": "tags" },
    { "type": "filter", "path": "createdAt" }
  ]
}

numDimensions is 256 for the builtin embedder and 384 once @xenova/transformers is installed. Without this index Mongo still works: vector search falls back to scoring candidates in process.