Spawn

A production-grade game engine written in Rust.

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Spawn

Rust game engine with archetype ECS, wgpu rendering, Rapier physics, and Lua scripting.

Status: v0.1.0 — Phase 1 complete. All 14 crates implement their core APIs against written specifications (docs/specs/), with 639 tests across the workspace. The engine integration loop, visual editor, and rollback netcode are Phase 2. Release notes: docs/releases/v0.1.0.md.

Workspace

Crate	Purpose
spawn-core	Math, primitives, errors. #[repr(C)], f32, right-handed, column-major. Zero deps.
spawn-ecs	Archetype ECS: queries, deferred commands, conflict-detecting parallel scheduler.
spawn-platform	Window, run loop, OS event translation (winit, fully wrapped).
spawn-input	Device state, action mapping, contexts, runtime rebinding (gilrs gamepads).
spawn-render	wgpu renderer: pipeline cache, validated render graph, forward pass.
spawn-asset	Async loading, typed handles, day-one hot-reload via Arc-swap.
spawn-audio	kira mixer: buses, spatial attenuation/panning, null-device fallback.
spawn-physics	Rapier 2D/3D behind dim2/dim3 features, fixed-step, ECS sync.
spawn-script	Sandboxed Lua 5.4 (mlua): instruction budgets, memory caps, typed bridge.
spawn-editor	Headless editor framework: undo/redo command stack, selection, gizmo math.
spawn-net	UDP transport: byte-precise protocol, salt handshake, reliable channels.
spawn-ui	Retained flexbox-subset UI: incremental layout, hit testing, draw list.
spawn-debug	Logging, frame profiler, metrics, overlay data model. Zero deps.
spawn-build	Asset compiler: manifest, content hashing, incremental, deterministic pack index.

Building

cargo build --workspace
cargo test --workspace

Requires stable Rust (edition 2021). On Linux, cpal needs ALSA headers (libasound2-dev on Debian/Ubuntu). Tests run headless: GPU tests use a fallback adapter or skip, audio tests use the null backend.

The workspace builds under #![deny(warnings)]. The commit gate:

cargo clippy --all-features --all-targets -- -D warnings
cargo fmt --check
cargo test --workspace
cargo deny check

License

Spawn is licensed under the Business Source License 1.1.

• Free for non-production use (development, testing, evaluation)
• Converts to the Apache License 2.0 on 2029-05-14
• Commercial licensing: altug@bytus.io