Arcan

Rust-first agent runtime and daemon focused on harness quality, typed streaming events, and replayable state.

Install

cargo install arcan

Workspace

• crates/arcan-core: protocol, state, runtime contracts, orchestrator loop
• crates/arcan-harness: sandbox and filesystem guardrails, hashline edit primitives
• crates/arcan-store: append-only session event repositories
• crates/arcan-provider: LLM provider implementations (Anthropic Claude)
• crates/arcand: agent loop, SSE server, and HTTP routing
• crates/arcan-lago: Lago event-sourced persistence bridge
• crates/arcan: installable binary (cargo install arcan)

Usage

# Launch interactive TUI (default command).
# Re-attaches to the most recent session automatically.
cargo run -p arcan

# Run daemon explicitly
cargo run -p arcan -- serve

# Run daemon with Anthropic Claude
ANTHROPIC_API_KEY=sk-ant-... cargo run -p arcan -- serve

# Launch TUI explicitly
arcan chat

# CLI options
arcan --port 3000 --data-dir .arcan

Dev Watch Mode (Daemon + TUI)

# one-time install
cargo install cargo-watch

# starts daemon in watch mode, waits for /health, then opens TUI
./scripts/harness/dev-tui-watch.sh

Environment overrides:

# custom port/session/data directory
PORT=3200 SESSION=dev-1 DATA_DIR=/tmp/arcan-dev ./scripts/harness/dev-tui-watch.sh

# use real provider env vars instead of mock mode
ARCAN_MOCK=0 ./scripts/harness/dev-tui-watch.sh

Docs

• docs/architecture.md
• docs/roadmap.md
• docs/vision-and-status.md
• docs/lago-integration.md

Verify

cargo check
cargo test
cargo clippy