Rust internals

Everything on this page is merged on the main branch with tests and has been run by hand on macOS. Windows and Linux pass continuous integration only.

Control plane

• Task contracts in vekrun-types: Task, a fourteen-state enum (draft, ready, queued, claimed, running, waiting-on-dependency, waiting-for-approval, verifying, integrating, blocked, failed, cancelled, completed, archived), the legal transition table, Lease, AuditEvent, PolicyDecision. Property tests reject arbitrary illegal transitions.
• Store: SQLite through a migration runner; transactional transitions; an append-only journal enforced by triggers; leases with deadlines. A task that finishes lands in verifying, never in completed by its own report.
• Hierarchy: manager and worker roles; delegation depth and concurrent-agent caps; a child task’s budget and tool authority are bounded by its parent’s, property-tested; managers wait for children.
• Verification and integration: a verifier that receives objective, criteria, change set and artifacts, never the implementer’s self-assessment; a report contract that refuses a pass without evidence; bounded repair tasks with escalation; an integrator that previews the merge through git merge-tree and requires approval before touching protected state.
• Snapshots: uncommitted state captured before risky turns and integration; previewed, selective, undoable restore that skips files with unsaved editor changes.
• Agent Inbox: one prioritised list over approvals, escalations, decisions, reviews and blocked tasks, across every session.

Policy engine and credentials

A capability enum, deny by default, one decision and one audit row per request. Policy inputs are never prompt text: repository content, instruction files, tool results, terminal output and model replies are data. Credentials live in the OS keychain behind a secret-free index with a migration ledger; keys are deleted when a provider is removed; nothing crosses into the webview. Before an agent command runs, an isolation check reports what the host can enforce; operations that need isolation the OS cannot provide fail closed. Per-call approval is mandatory and no auto-approve control exists until OS-enforced sandboxes land.

Terminal

PTY sessions are owned in Rust with output coalescing and pause/resume as back-pressure, adopted after a measured spike: a raw channel plus coalescing, with xterm.js rendering as the throughput ceiling (about 12 MB/s), and a Rust-side terminal model tapped off the coalescer at about 245 MB/s that backs the read_terminal tool and the OSC policy. Shell integration marks (OSC 133) provide exit codes, durations and cwd. Hyperlinks open only after the real URL is shown; OSC 52 clipboard writes are refused by design. SSH uses russh with strict host keys and an in-process server test. Session restore rebuilds layout and scrollback under an honest divider and never claims a dead process is alive.

Provider gateway

Streaming adapters for Anthropic, OpenAI-compatible endpoints and Gemini, each with deterministic mocks and opt-in live tests; a capability registry that records “unknown” rather than inventing context sizes or prices; routing profiles (explicit, quality, latency, cost, balanced, custom); a budget hierarchy global > project > team > agent > task where a child cannot expand a limit; a usage ledger; retries with backoff on transient errors; fallbacks only when policy allows. Ollama and LM Studio detection reports installed and reachable separately.

Files and Git

Git runs through the user’s installed git for anything that writes (commit, switch, branch, stash, worktree) so hooks and credential helpers apply; reads use a Rust Git library. Nothing is forced; destructive actions need confirmation and are audited. The file service lists under git check-ignore, refuses paths outside the project, caps reads, refuses binaries, and writes only when the hash the editor last read still matches the disk, otherwise it reports a conflict. Monaco is bundled locally with its workers; nothing loads from a CDN.

See Architecture for the component map and Progress for milestone status.