devpage

Dependencies

Every crate devpage depends on, with the version Cargo.lock resolves and what devpage uses it for, and the build script and builder that make what it embeds. It is a reference page under Engineering, for someone reading or changing the code; the code map maps the modules named here.

devpage is a Cargo workspace of four crates: devpage, the binary, at the top; devpage-design, the design engine, in design/; devpage-design-wasm, the engine built for the browser, in design/wasm/; and devpage-design-module, which builds that module into assets/vendor/, in design/module/. devpage and devpage-design are the two that are published, together, at a release (Release); the other two never are. Each crate's list is its [dependencies] and [build-dependencies], and devpage's one [dev-dependencies] entry, marked below. The roles below say what each crate does in devpage. Why a crate was chosen over another is recorded nowhere, except where a code comment says so, and this page doesn't guess.

The server

Crate Locked version Licence What devpage uses it for Where
axum 0.8.9 MIT The HTTP server: the router and its routes, the handlers, Json for the comment requests, the request-logging middleware, the server-sent event response (axum::response::sse) and axum::serve — also for the server devpage pdf and the Chrome tests start internally. src/server.rs, src/main.rs, src/pdf.rs, src/comments.rs (tests)
tokio (feature full) 1.54.1 MIT The async runtime (#[tokio::main]), binding the address (TcpListener), the broadcast channel that carries changes, background external-link checks, and reading files in handlers (tokio::fs). src/main.rs, src/server.rs, src/watch.rs, src/check.rs, src/pdf.rs, src/comments.rs
tokio-stream (feature sync) 0.1.19 MIT BroadcastStream, which turns a subscription to the change channel into the stream the event route sends; ReceiverStream and the Stream trait, which make the design store's updates the watch stream's response. src/server.rs, src/designs.rs
clap (feature derive) 4.6.7 MIT or Apache-2.0 The command line: serving, check and pdf, their flags, --help and --version. src/main.rs

Markdown and code

Crate Locked version Licence What devpage uses it for Where
comrak 0.57.0 BSD-2-Clause Markdown: rendering pages to HTML with the GFM options, parsing a page to find its Topics section, and the code-fence plugin hook (SyntaxHighlighterAdapter) the highlighter implements. src/render.rs, src/nav.rs, src/highlight.rs
syntect 5.3.0 MIT Syntax highlighting: finding a language by name or extension and emitting class-based HTML (hl- prefixed spans). src/highlight.rs
two-face 0.5.2 (+bat-0.26.1) MIT or Apache-2.0 The syntax set syntect highlights with. The code comment gives the reason: it is the set bat ships, which includes Swift, TypeScript, TOML and YAML besides syntect's defaults. src/highlight.rs

Widgets

Crate Locked version Licence What devpage uses it for Where
oxc (features transformer, codegen, semantic) 0.153.0 MIT Compiling widgets from TSX to browser modules: parsing, finding the widget names a file uses without declaring (semantic), React's automatic JSX runtime and TypeScript stripping (transformer), and printing the module (codegen). Its rust-version = 1.97 sets devpage's minimum Rust. Cargo.toml pins it exactly (=0.153.0). src/widgets.rs

Files and watching

Crate Locked version Licence What devpage uses it for Where
notify 8.2.1 CC0-1.0 The file watcher: the platform's recommended watcher, on the served folder, recursively. src/watch.rs
ignore 0.4.33 Unlicense or MIT Walking the served folder to build the index while honouring every .gitignore in it (WalkBuilder), and matching changed paths against them (Gitignore). src/index.rs
globset 0.4.20 Unlicense or MIT A site's watch patterns: compiled into one glob set and matched against each changed path. src/document.rs
mime_guess 2.0.5 MIT The Content-Type of a file that isn't Markdown or a document file, guessed from its extension, or application/octet-stream. src/server.rs

Documents, comments and data

Crate Locked version Licence What devpage uses it for Where
serde (feature derive) 1.0.229 MIT or Apache-2.0 Deserializing document files into the kind-tagged config with deny_unknown_fields, comment threads, and the comment requests' bodies. src/document.rs, src/comments.rs, src/server.rs
serde_yaml 0.9.34 (+deprecated) MIT or Apache-2.0 Parsing document files and writing and reading comment thread files; its messages, with line and column, are what a bad document file prints. The published version is marked +deprecated and its README says the project is no longer maintained. src/document.rs, src/comments.rs
serde_json 1.0.154 MIT or Apache-2.0 The comment requests' JSON answers, the list of broken links the problems bar carries for the page script to mark, and the widgets' props, widget lists and __devpageUses. src/server.rs, src/render.rs, src/widgets.rs
Crate Locked version Licence What devpage uses it for Where
reqwest 0.13.5 MIT or Apache-2.0 Checking external links (one shared client, asking for HTML as a browser does, with a 10-second first wait and a 30-second retry); the route tests' HTTP client. src/check.rs, src/server.rs (tests)
futures 0.3.34 MIT or Apache-2.0 Running external-link checks at once (join_all) and driving chromiumoxide's event stream (StreamExt). src/check.rs, src/pdf.rs, src/comments.rs (tests), src/designs/canvas_tests.rs
chromiumoxide (features fetcher, rustls, zip8) 0.9.1 MIT or Apache-2.0 Driving Chrome over the DevTools protocol for devpage pdf (Page.printToPDF), a slide's PNG (Page.captureScreenshot), devpage video (evaluating its recorder, pressing →, sizing the window) and the Chrome tests; fetcher downloads chrome-headless-shell — and, for devpage video only, Chrome for Testing — into devpage's cache folder the first time one is needed. src/pdf.rs, src/slide_png.rs, src/video.rs, src/comments.rs (tests), src/designs/canvas_tests.rs

Video

Crate Locked version Licence What devpage uses it for Where
async-tungstenite (features tokio-runtime, tokio-rustls-native-certs) 0.32.1 MIT The WebSocket to GPT-Live for devpage video, over rustls with the system's root certificates. chromiumoxide already speaks DevTools through it, so it adds no crate. src/video/live.rs
base64 0.22.1 MIT or Apache-2.0 The voice's PCM in GPT-Live's events and on its way into the page, and the finished mp4 on its way back out. src/video.rs, src/video/live.rs

Designs

Crate Locked version Licence What devpage uses it for Where
devpage-design (feature server) 0.2.0 (path design/, published beside devpage at the same version) MIT The design engine: parsing, resolving, painting a PNG, the watch stream's messages and patches — for the design store, and for devpage check through it — and, with server, the Designs service's server side. src/designs.rs, src/server.rs
tonic (feature codegen) 0.14.6 MIT The gRPC server side of the watch stream: the Designs service's request and response types and its streaming response. axum routes to the service itself, so tonic's own router is not used. src/designs.rs, src/server.rs
tonic-web 0.14.6 MIT GrpcWebLayer, which serves the gRPC service as gRPC-Web, so the browser can call it with fetch and no proxy. src/server.rs
tower 0.5.3 MIT ServiceBuilder, wrapping the gRPC service in the gRPC-Web layer before axum routes to it. src/server.rs
prost (dev) 0.14.4 Apache-2.0 Decoding watch-stream messages in the route tests. src/designs.rs (tests)

devpage has no build script and builds no WebAssembly: the binary embeds the vendored assets/vendor/design-engine.wasm and assets/vendor/design-engine.js as the built-in assets /__devpage/design-engine.wasm and /__devpage/design-engine.js.

Errors

Crate Locked version Licence What devpage uses it for Where
anyhow 1.0.104 MIT or Apache-2.0 Errors: Result, .context(…) to say what devpage was doing, and bail!. main returns anyhow::Result, so a failure prints in anyhow's format — Error: <context>, then Caused by: and the underlying errors. most modules

The design engine's crates

devpage-design, the design engine

It does no I/O; it is given file contents. Its build script, design/build.rs, compiles design/proto/design.proto with protox and generates the messages with tonic-prost-build — and, when the server feature is on, the Designs service's server side — so the server and the module share one set of message types, and the proto ships inside the crate. devpage turns server on; the module leaves it off.

Crate Locked version Licence What the engine uses it for Where
taffy (features std, taffy_tree, flexbox, content_size) 0.15.1 MIT Auto layout: rows and columns as flexbox, hug and fill, and absolute placement. design/src/render.rs
parley 0.12.0 Apache-2.0 or MIT Text: shaping, measuring and line breaking over the embedded Inter faces, and the glyph runs the display list draws. design/src/render.rs
vello_cpu 0.3.0 Apache-2.0 or MIT The CPU backend: replays the display list into an RGBA buffer, for the PNG and for a canvas without WebGPU; samples a shadow's shape before the painter blurs it. design/src/render.rs
png 0.18.1 MIT or Apache-2.0 Decoding PNG images a design uses, while resolving; encoding test images. design/src/resolve.rs, design/src/render.rs (tests)
zune-jpeg 0.5.15 MIT, Apache-2.0 or Zlib Decoding JPEG images a design uses, while resolving, strictly, so a truncated file is a problem. design/src/resolve.rs
prost 0.14.4 Apache-2.0 The watch stream's messages: encoding a scene and its patches, and decoding them in the module. design/src/proto.rs, design/src/wire.rs
tonic (feature codegen; only with server) 0.14.6 MIT What the generated Designs server is written against. generated into design/src/proto.rs
tonic-prost (only with server) 0.14.6 MIT The protobuf codec the generated service encodes its messages with. generated into design/src/proto.rs
protox (build) 0.10.0 MIT or Apache-2.0 Compiling design/proto/design.proto in Rust, so building needs no protoc. design/build.rs
tonic-prost-build (build) 0.14.6 MIT Generating the messages, and with server the service, from the descriptors protox compiled. design/build.rs

devpage-design-wasm, the engine in the browser

A cdylib built only for wasm32-unknown-unknown, by devpage-design-module.

Crate Locked version Licence What the module uses it for Where
devpage-design 0.2.0 (path design/) MIT The engine: applying scenes and patches, layout, the display list, the CPU backend, hit-testing. design/wasm/src/lib.rs
prost 0.14.4 Apache-2.0 Decoding the watch stream's messages (Message::decode) before they are applied to a canvas's scene. design/wasm/src/lib.rs
vello 0.11.0 Apache-2.0 or MIT The GPU backend: the display list replayed into a vello scene and drawn with WebGPU through wgpu. design/wasm/src/gpu.rs
wasm-bindgen 0.2.129 MIT or Apache-2.0 Every export the page calls, and the canvas and GPU handles passed in from JavaScript. Pinned to the version wasm-bindgen-cli-support generates bindings for. design/wasm/src/lib.rs, design/wasm/src/gpu.rs
wasm-bindgen-futures 0.4.79 MIT or Apache-2.0 Exporting Gpu::open, which awaits WebGPU's adapter and device, as an async function the page receives as a promise. design/wasm/src/gpu.rs
web-sys (feature HtmlCanvasElement) 0.3.106 MIT or Apache-2.0 The <canvas> element a GPU target draws into. design/wasm/src/gpu.rs

devpage-design-module, the module's builder

cargo run -p devpage-design-module builds devpage-design-wasm for wasm32-unknown-unknown with a nested cargo build --profile wasm --locked into target/design-module/, runs wasm-bindgen on the result, and writes the module and its bindings into assets/vendor/ with design-engine.fingerprint. The wasm profile in the top Cargo.toml inherits release and optimises for size (opt-level = "s", lto, one codegen unit, stripped), because the page downloads the module. Its test fails when the fingerprint no longer matches the sources (Developing devpage).

Crate Locked version Licence What the builder uses it for Where
wasm-bindgen-cli-support 0.2.129 MIT or Apache-2.0 wasm-bindgen as a library: the module and its JavaScript bindings, with no CLI to install. Pinned to exactly the wasm-bindgen version the module uses, as wasm-bindgen requires. design/module/src/main.rs
sha2 0.10.9 MIT or Apache-2.0 The fingerprint: a SHA-256 of everything the module is built from. design/module/src/lib.rs
toml 0.9.12 (+spec-1.1.0) MIT or Apache-2.0 Reading Cargo.lock for the module's locked dependency tree, and the wasm profile from Cargo.toml. design/module/src/lib.rs

Licences and code that isn't a crate

Licences are as each crate's own Cargo.toml declares them. devpage itself is MIT — see Installing devpage.

Four more pieces of third-party work are built into the binary but aren't crates: the vendored pele bundle, the JavaScript that draws diagrams; the vendored React bundle, which widgets run with; the vendored icons, Lucide's icon set (ISC) and GitHub's mark (CC0); and the Inter typeface — regular, medium, semibold and bold, in design/fonts/ — which the design engine embeds with include_bytes! and sets every design's text in. Inter is under the SIL Open Font License 1.1, whose text ships beside the fonts as design/fonts/LICENSE.txt.

The error messages each failure produces are listed in the configuration reference.