Architecture

This site is the documentation. The design notes stay in the repository, where they sit next to the code they describe and are reviewed with it. This page says where they are.

docs/ARCHITECTURE.md

docs/ARCHITECTURE.md is the deep reference: what is true about the implementation right now. Goals and non-goals, Cx and the View trait, what #[component] and rsx! generate, the hook list with its exact semantics, the runtime (store, sweep, multi-pass, repaint policy, <Suspense>), the layout engine over taffy including the lite path for list rows, the element list, the crate layout, the platform notes, and the testing strategy.

The guide on this site is written for someone building an app; ARCHITECTURE is written for someone changing the library. When a guide page summarizes something, it links the section there rather than repeating it.

docs/adr/

docs/adr/ is the decision log: one file per design decision, grouped by domain — core, runtime, layout, elements, fonts, a11y, app. Each records when the decision was made, what was decided, what was turned down and why, and what it costs.

The discipline is deliberately narrow, and it is what makes the log worth reading:

• An ADR is a record of a moment. It is never rewritten to say something else.
• A new decision gets a new file. A changed decision gets a new file that supersedes the old one; the old file keeps its text and gains "superseded by" in its status line.
• ARCHITECTURE.md says what is true now and links the ADR. When the two disagree, ARCHITECTURE is the one that is wrong about the code.

So if you want to know why use_state hands back a guard rather than a (value, setter) pair, why hook deps are hashed instead of compared, why on_* props are fused into one closure, or why layout runs on taffy rather than egui_flex — the answer is a short file with a date on it, and it has not been edited since.

API documentation

/api/ is cargo doc for the four public crates: egui-reactor, egui-reactor-elements, egui-reactor-app and egui-reactor-macros. It is generated into this site by the same build, so it always matches the commit the site was built from. It is the right place for exact signatures; this site is the right place for how the pieces fit together.

The repository

github.com/fand/egui-reactor. Issues and pull requests welcome; the tests to run before opening one are in the README.