Roadmap

This page covers only features as you encounter them. Internal phases, progress percentages, and implementation details live in the GitHub repository.

Planned

Bundler

Public WASM AST API

Expose the ZNTC AST as a WASM module so it can be consumed outside Node and the browser. The WASM build that today powers the Playground and Metafile Analyze pages will be stabilized and published as a user-facing API. Depends on AST schema stabilization.

External Zig plugins

Zig plugins currently exist only for built-in transforms (worklet, Fast Refresh). User-authored Zig modules will be loadable as plugins, statically linked at build time and called in-process. No JS↔native serialization overhead, but the Zig compiler must be available at build time.

Rollup plugin context API extension (ESTree AST)

The vitePlugin() adapter supports the main Rollup hooks (resolveId · load · transform · renderChunk · generateBundle) and most fields of getModuleInfo(). Remaining items are parts of the plugin context API (this.parse() · this.resolve() · this.emitFile() · ModuleInfo.meta) and ModuleInfo.ast — an ESTree adapter that exposes each module’s ESTree-compatible AST to plugins. It depends on converting ZNTC’s internal AST to the ESTree shape.

Per-chunk CSS splitting

import './style.css' auto-emit, @import inlining, and Lightning CSS minification already work. Splitting CSS per output chunk during code-splitting is deferred. (.module.css class-name hashing / scoping is already built in for app mode — see Plugin Recipes / CSS Modules.)

Refined dead-code elimination (innerGraph)

Straight-line dead stores on local variables are eliminated. Dead-store analysis across if / for / try control flow is in progress.

lazyBarrel refinement

Barrel re-exports (export * from, export { X } from, import * as X; export { X }) skip compilation for pure / local / namespace patterns. Wrapper barrels that mutate imported bindings (e.g. lodash-es’s lodash.default.js) currently disable lazy mode entirely as a conservative fallback. Refining this to apply lazy mode to non-mutating parts only is pending. See Tree-shaking for current limits.

mangleProps

Cross-module property mangling, esbuild-style. Not implemented yet.

Improved module concatenation

Scope-hoisting at the level of rspack / rolldown.

Persistent disk cache

Only an in-memory parse cache + resolve cache lives across rebuilds within a watch / serve session. A persistent on-disk cache to speed up cold rebuilds is on the backlog.

Module Federation

Microfrontend code / asset sharing, comparable to rspack. Not implemented yet.

Lazy compilation

On-demand module compilation for faster dev startup. Not implemented yet.

Transpiler

.d.ts emission (isolatedDeclarations)

Currently delegated to tsc. Native isolatedDeclarations-based emission is planned.

Dev server

Converging to a single Zig dev server

Two dev servers coexist today:

• Zig native (zntc serve / zntc dev) — standalone, no Node required.
• JS (zntc dev <root> app mode) — used to delegate to JS-ecosystem plugins (postcss / sass).

The long-term goal is to vendor BoringSSL, abstract the plugin host, and converge on the Zig server (similar to Bun’s model). This sits behind the stability / CSS / ecosystem milestones.

Ecosystem

Plugin examples

Reference plugins for common cases: PostCSS, Tailwind, SVG, YAML.

Migration guides

Expand the esbuild → ZNTC and Vite → ZNTC mapping tables. Some material already lives under Migration.

Framework integration (Next.js · Remix · SvelteKit · Expo)

Each of these ships its own bundler tightly coupled to the framework, so an adapter ends up being a partial reimplementation of the framework’s compiler. This is the last milestone.

• Expo: A meta-framework on top of React Native. Plain React Native apps already build via --platform=react-native, but integrating with Expo Router’s filesystem-routing manifest, the expo prebuild step, and the EAS build pipeline requires a dedicated adapter.

Vite-compatible mode

Read vite.config.js directly for zero-cost migration. Long-term goal.

Current limitations

Cannot build Next.js / Remix directly

These frameworks bake the bundler into the framework itself — RSC payload serialization, filesystem-routing manifests, loader/action server-client separation. A general-purpose bundler cannot stand in for them. Plain React / Vue / Svelte SPAs and React Native (Metro-compatible output) are supported.

.module.css auto-transform in core --bundle mode

App mode (zntc dev / zntc build) supports .module.css class-name hashing / scoping out of the box — see Plugin Recipes / CSS Modules. Core --bundle mode does not auto-transform .module.css; go through the Vite adapter or a user plugin (PostCSS Modules / Lightning CSS Modules) instead.

Per-chunk CSS splitting

CSS is emitted as a single artifact even when JS is code-split. Per-chunk CSS is deferred.

Persistent disk cache · Module Federation · Lazy compilation · mangleProps

See the corresponding “Planned” items.

Control-flow-aware dead stores

Dead assignments inside if / for / try may be preserved. Only straight-line dead stores are eliminated today.

Wrapper-barrel mutation pattern

When a barrel module mutates an imported binding (some libraries do this — e.g. lodash-es), the lazy-barrel optimization is disabled wholesale for that module. Correctness is preserved, but the bundle can be larger than necessary.

Large tsconfig paths (hundreds of entries)

Only the first resolve walks the array linearly; subsequent resolves hit the resolver cache. No measurable impact at normal project sizes.

Public WASM API

Limited to internal use by the Playground and Metafile Analyze pages. There is no stabilized public API for users to import directly yet (see the “Planned” entry above).