Shared foundation library for the Arc ecosystem.
arclib provides the common building blocks used across Arc projects (ArcHub, MyClerk, ArcShell, ArcMail):
- Crypto — ChaCha20-Poly1305 (AEAD); X25519 and ML-KEM-768 (post-quantum) key exchange; Ed25519 and ML-DSA-65 (post-quantum) signatures; hybrid identity keys; HKDF-SHA256, X9.63-KDF, Argon2; HMAC-SHA256, SHA-256, CRC-16/32; key rotation and key wrapping; an at-rest SQLite cipher; ZSTD compression.
- Protocol — the MyClerk Protocol layer: tiered message framing (tiers 0–5), opcodes/categories/extensions, fragmentation, a hybrid post-quantum handshake (X25519 + ML-KEM-768), Tier-5 sessions with automatic key rotation, and mutual identity authentication. MyClerk is published as an IETF Internet-Draft; arclib is its reference implementation.
- Transport — MyClerk over WebSocket (sessions, handshake, dispatch).
- LLM — a generic LLM-over-MyClerk contract plus Ollama and OpenAI-compatible clients.
- DB — database abstraction for PostgreSQL, SQLite, MariaDB/MySQL with encrypted fields.
- And more — rate limiting, WebAuthn/Passkeys, JSON5, structured logging, config loader, MessagePack.
Go is the reference implementation; the Kotlin (kt/) and JavaScript/TypeScript (js/) mirrors
track it against shared cross-validation test vectors for byte-identical output. The most recent
additions (hybrid post-quantum handshake, Tier-5 sessions, identity authentication) land in Go
first; the mirrors follow.
go get arcan-it.de/arclib
arcan-it.de/arclib — hosted on GitHub.
Current version: v1.4.0.
arclib is dual-licensed:
- The
crypto/package is licensed under the Apache License 2.0 (seecrypto/LICENSE) — permissively reusable. - Everything else is licensed under the Business Source License 1.1 (see
LICENSE).
Under BSL 1.1, production use is free for organizations with annual revenue below EUR 1,000,000; larger organizations require a commercial license. Each released version automatically converts to the Apache License 2.0 four years after its release.
The Business Source License is not an OSI-approved open-source license, but every version becomes Apache-2.0 on its change date. For commercial licensing, contact Arcan Consulting.