Libraries & downloads

QuantumLedger ships as four Python packages. The client side is open source (Apache-2.0); the hosted server is source-available (BUSL-1.1). You only need the pieces relevant to what you're doing.

quantumledger — the SDK & CLI

Install: pip install quantumledger · extras: [aer], [qiskit_runtime], [braket], [azure] · License: Apache-2.0 · Package dir: packages/ql-sdk

The open-source client. What it gives you:

• the @ql.capture decorator / context manager to record quantum jobs;
• an offline local ledger (quantumledger.store.LocalLedger, SQLite, no account);
• the ql command-line tool — see the CLI reference;
• vendor connectors (a plugin system) for Aer, IBM Qiskit Runtime, Braket, Azure, IonQ;
• content-hash-idempotent push to a hosted store (ql push).

pip install "quantumledger[aer]"

quantumledger-core — the provenance engine

Install: pip install quantumledger-core · extra: [postgres] · License: Apache-2.0 · Package dir: packages/ql-core

The shared foundation used by both the SDK and the server:

• the SQLAlchemy provenance data model (Backend, CalibrationSnapshot, Circuit, Compilation, Run, Result, ReproductionEvent);
• canonical JSON hashing + Merkle run_hash and the DB-trigger immutability layer;
• the deterministic simulator + drift engine;
• reproduce / scoring / diff (Hellinger fidelity, TVD, Jensen–Shannon, the diff engine);
• the open qlprov/* JSON schemas (see Open schemas).

Runs on SQLite (offline / small self-host) or PostgreSQL (hosted) from one schema.

quantumledger-crawler — the corpus crawler

Install: pip install quantumledger-crawler · License: Apache-2.0 · Package dir: packages/ql-crawler

Collects public-QPU calibration data, normalizes it to qlprov/calibration/1.0, applies terms-of-service redistribution policies, deduplicates, and ingests it into the public corpus. Ships a FixtureSource (offline) and a LiveSource skeleton for real vendor APIs. See Corpus & leaderboard.

quantumledger-server — the hosted platform

Install: pip install quantumledger-server (or use the docker-compose in deploy/) · License: BUSL-1.1 (source-available) · Package dir: server

The FastAPI application: ingestion + read API, the server-rendered web UI, Result Cards + badge service, the reproduce engine, the compliance rule engine, Ed25519 attestations, accounts/entitlements/RBAC, and admin. See Deployment & self-hosting and the API reference.

Which do I need?

Next: CLI reference.