Howl

Howl is a C ABI embeddable terminal stack.

The product boundary is the ABI: hosts embed PTY, VT, and render libraries through public C headers, while each host owns platform UX, event loops, wake policy, presentation cadence, runtime orchestration, and backend resources.

Repositories

• howl-pty: PTY-backed child transport, lifecycle, resize, input/output, wait/kick, and control signals.
• howl-vt: terminal parser/state, visible-surface truth, selection, input encoding, and host-facing protocol consequences.
• howl-render: backend-agnostic render contracts, geometry, text shaping, prepared surfaces, and submit/retire state.
• howl-linux-host: reference Linux desktop host using SDL/OpenGL.

See libs.yaml for the owner tree and project-memory.md for timestamped project memory.

Build

Run the repo-wide gates from the workspace root:

zig build check
zig build test

Package-specific gates can also be run from each subrepo:

zig build check
zig build test

Boundary

• Hosts depend on howl-pty, howl-vt, howl-render, and vendored host contracts only.
• PTY owns process transport, not terminal semantics.
• VT owns terminal truth, not backend presentation.
• Render owns backend-agnostic render contracts, not host upload or present.
• Hosts own platform integration.

Status

Howl is a young private product. Public C ABI clarity is prioritized over compatibility shims or preserving stale names.