Upgrading

Run the installer again — it replaces the binary in place — or cargo install webfluent --force. wf --version says what you have. Update wf-lsp and the editor extension with it: the language server is built from the same compiler.

The full notes for every release are in RELEASE_NOTES.md; what follows is what an upgrade asks of you.

Nothing to change in your code. New:

• Offline: name offline in the config for a service worker, writes kept for later, and an update flow (chapter 19).
• Peers: peer link = rtc(signal: …), a WebRTC data channel to another page (chapter 18).
• env from a .env file and the shell, on top of the config (chapter 30).
• Unknown config keys are reported, with the key they probably meant.
• Pagination: paginate: .page, .items, .loadMore(), .hasMore.
• ?lang= opens a page in that locale, as the hreflang alternates promise.
• class-exported libraries work through external: a class is constructed when called.
• Every standard DOM event is accepted in on ….

Fixed, and worth knowing because they could have bitten you:

• A private env value no longer reaches the bundle. 4.0 refused a page that read a private name, but still wrote the whole env map into app.js. If you deployed 4.0 or 4.0.1 with a secret in env, rotate it.
• An action's parameters are its own: action move(by: Number) read by as a signal and threw.
• head { } tags may read a page's derived values.
• A resource's state, data and error, and a socket's messages, show their values in text.
• navigator and location compile as the browser's.
• Two declarations on one line — theme T { color-primary: #0F766E radius-md: 14px } — are two, not one.
• S04 reports two pages on one route; A12 counts an h1 in each branch of an if as one.

4.0 changed what the compiler allows. wf migrate handles the mechanical part and names every place that needs a decision:

• env is public or private. A page may only read a name beginning PUBLIC_ or listed in public_env. The migration adds every name your pages already read to public_env and prints the list: read it, because public means anyone who opens the site can read the value.
• An on* attribute is an error (onclick: "…"); write on click { }.
• A URL a browser would run is refused — javascript:, data:, vbscript:, blob:, file: in href:, src:, to:, poster: or navigate().
• Stores are built on first read, not at boot. A store whose set-up must run anyway takes eager: true.
• A persist value follows other tabs. sync: false opts out.
• WF.store and WF.host were renamed in the runtime surface.
• Layouts stay as written: a Row no longer turns into a column on a narrow screen by itself. The migration adds .stacks to keep the old behaviour.

WebFluent 3 introduced the grammar this guide describes: lowercase declarations, one positional argument, flags after a dot, on click { } handlers, style { } blocks of CSS.

A WebFluent 2 file (Page Home (path: "/") { … }) is refused by wf build with a pointer to the migration. wf migrate rewrites every .wf under src/ into the current grammar — a change of spelling that builds to what it built before — and wf migrate --wfx writes the result in the indented layout.