strata

StrataDB {version}

StrataDB is an embedded database: it runs inside the process against a local directory, like SQLite or DuckDB — no server, no port, no connection string. One database holds five data primitives on one branch-aware, time-travelling substrate. This skill matches strata {version}; the binary and the wheel are self-describing (see "Deeper reference" below).

Open a database (Python)

import stratadb

db = stratadb.open("./mydb")       # durable directory (created if absent)
db = stratadb.open(cache=True)     # ephemeral, in-memory
db = stratadb.from_env()           # path from $STRATA_DB

Never rely on the current directory — stratadb.open() with no target raises invalid_argument.cli.no_database. Use a context manager or db.close().

Choose a primitive

Data shape	Use	Namespace
Opaque value by key	key-value	db.kv — values are bytes; str encodes as UTF-8
Structured record, addressed by field	JSON documents	db.json — read/write inside a doc by path ("$.name")
Embeddings, similarity search	vectors	db.vectors — collections fix dimension + metric
Ordered, append-only history	events	db.events — hash-chained; count is len()
Relationships, traversal, analytics	graph	db.graphs — both edge endpoints must exist first

db.kv.put("greeting", "hello");  db.kv.get("greeting")        # b"hello"
db.json.set("user:1", "$", {"name": "Ada"});  db.json.get("user:1", "$.name")
db.vectors.create_collection("notes", dimension=384)
db.vectors.upsert("notes", "n1", vec, metadata={"kind": "note"})
db.vectors.query("notes", query_vec, k=5)
db.events.append("deploy", {"ok": True})
db.graphs.create("g"); db.graphs.add_node("g", "a"); db.graphs.add_node("g", "b")
db.graphs.add_edge("g", "a", "link", "b")

Branches and time travel

Every primitive is branch-aware. A fork is cheap and isolates writes; the default branch is named default (not main):

db.branches.fork("default", "experiment")
exp = db.at(branch="experiment")       # scoped view over the same handle
exp.kv.put("k", "risky-value")
db.kv.get("k")                         # None on default — isolated