Migrating from rbx

rbx was a well-built, fully typed React wrapper for Bulma — its last commit was June 2019. @allxsmith/bestax-bulma is actively maintained, targets Bulma v1 (CSS variables, dark mode, Grid), and covers the same component surface.

rbx users are stuck in a way most legacy-library users are not, for two reasons:

• rbx pins Bulma itself. It ships bulma@0.7.5 as a direct dependency, plus bulma-badge, bulma-divider, bulma-pageloader and bulma-tooltip. Your app cannot pick its own Bulma version while rbx is installed, so there is no incremental path to Bulma v1.
• React 19 removed defaultProps on function components, which is what rbx's forwardRefAs base is built on.

Migrating clears both at once. The codemod deletes five dependencies — rbx and all four of its Bulma extensions — and replaces them with @allxsmith/bestax-bulma and Bulma v1.

See how they compare

For a capability-by-capability comparison of bestax against the other major React libraries, see the latest edition of The State of React.

Run the codemod

# Preview the changes and the TODO report without writing anything
pnpm dlx bestax-migrate rbx src/ --dry

# Apply it
pnpm dlx bestax-migrate rbx src/

(npx bestax-migrate … works the same.) Useful flags: --print echoes transformed files to stdout; --extensions controls which files are considered (default js,jsx,ts,tsx,scss,sass); --css bestax|bulma|keep picks the stylesheet target (default bestax); --no-deps skips the package.json update.

The codemod uses jscodeshift to rewrite your source in place:

• Imports — rbx → @allxsmith/bestax-bulma, including namespace imports and const { Item } = Card; destructuring. Deep imports like rbx/base/theme are flagged with a pointer to bestax's Theme and ConfigProvider.
• Components — every rbx export and its dot-notation compounds are mapped, e.g. Card.Footer.Item → Card.FooterItem, Tag.Group → Tags, Column.Group → Columns, Table.Cell → Table.Td, PageLoader/Loader → Loading, Level.Item align="right" → Level.Right, Navbar.Segment align="end" → Navbar.End, and Title subtitle → SubTitle.
• Props — bare boolean modifiers gain their bestax prefixes (outlined → isOutlined, rounded → isRounded), state="loading" → isLoading, and the Bulma v1 spacing helpers replace the removed is-*less classes (marginless → m="0", radiusless → radius="radiusless"). Most of rbx's helper values need no remapping at all — its textAlign, textWeight and display unions are already bestax's.
• Breakpoint objects — all three rbx shapes flatten: responsive={{ tablet: { display: { value: 'flex' } } }} → displayTablet="flex", <Column tablet={{ size: 6 }}> → sizeTablet={6}, and <Column.Group tablet={{ gapSize: 2 }}> → gapTablet={2}.
• Structure — rbx's badge and tooltip helper props become real wrapping components (<Button tooltip="Hi" /> → <Tooltip label="Hi"><Button /></Tooltip>), Select.Container and Image.Container fold onto the component they wrap, and Help/Label become the plain Bulma markup bestax expects.
• Stylesheets — Bulma 0.9-era @import lines become @use "bulma/sass" with (…), and the bulma-badge / bulma-divider / bulma-pageloader / bulma-tooltip imports are dropped: bestax ships Badge, Divider, Loading and Tooltip itself.

The TODO report

Anything the codemod cannot convert safely is left in place with a // TODO(bestax-migrate): … comment on the enclosing statement, and summarised in a report at the end of the run. Nothing is ever silently dropped or best-guessed.

The four you are most likely to see, in the order they show up when the codemod is run over rbx's own documentation examples:

What	Why	What to do
component:Icon	bestax's Icon takes a required name, which cannot be read out of an rbx <FontAwesomeIcon icon={faHome} /> child	<Icon name="home" library="fa" variant="solid" />
component:Tile	Bulma v1 removed Tiles	Use Grid and Cell; see the Bulma 0.9 → 1 guide
component:File.*	bestax's <File> renders the whole file-input structure from its own props	Drop the parts; set label, hasName, isBoxed on <File>
prop:as	rbx's forwardRefAs puts as on every component; bestax declares it on a smaller set, several narrowed to specific tags	Restructure, or render the tag directly

Generic, Tile, List, Fieldset, Numeric and Highlight have no bestax counterpart, so their imports are kept (trimmed and TODO-annotated) — your app still runs while you migrate them by hand.

Finish the migration

1. Install — the codemod already rewrote package.json; apply it with npm install (or pnpm/yarn). Expect a peer-deps report entry: rbx peer-depended on React ^16.8.6 and bestax-bulma needs React 18 or 19, so upgrade react/react-dom first. If you were on Font Awesome 5, bestax's optional peer wants FA ≥ 6.7 — upgrade, or install with npm install --legacy-peer-deps.
2. Styling follow-ups — pick a different CSS flavor if you need prefixed/no-helpers/light-only builds, and read the Bulma 0.9 → 1 guide for the styling changes that aren't code-level. Because rbx pinned Bulma 0.7.5, you are crossing two Bulma majors — expect more visual drift than the guide's 0.9 → 1 baseline describes. One deliberate change: bestax.css ships $primary as bestax blue (#1e6b99) rather than Bulma's stock turquoise — keep the stock look with --css bulma, or set your own brand color via the --bulma-primary-* CSS variables.
3. Theming — rbx's ThemeContext (rbx/base/theme) has no direct equivalent. bestax splits that job between Theme for CSS-variable overrides and ConfigProvider for the class prefix and icon library.
4. Verify — typecheck, build, and compare the rendered app against the pre-migration UI.

Version support

The codemod maps the rbx v2 API (v2.2.0 is the final release). The mapping table is checked against rbx's own export surface in both directions, so a component it does not know about is reported as unknown-component rather than being silently skipped.

Coming from a different library?

If you're using a specific React Bulma package that isn't supported by the migration tool yet, open a feature request naming the package and the components you use — the codemod platform is built to grow new source libraries.