sveltejs/kit · error · Error

Cannot build with ${JSON.stringify(file)} because Bun treats

Error message

Cannot build with ${JSON.stringify(file)} because Bun treats literal `*` characters in route paths as wildcards. Rename the file or route to remove the `*` character.

What it means

adapter-bun emits route files into a Bun built-in HTTP router/manifest where a literal '*' in a path is interpreted as a wildcard, conflicting with SvelteKit's rest-route syntax (e.g. [...slug]). The adapter therefore rejects any generated route file path containing '*' at build time.

Source

Thrown at packages/adapter-bun/index.js:89

 */
async function asset_meta(file, precompress = false) {
	const hash = await hash_file(file);

	/** @type {{ hash: string, mtime: number, br?: boolean, gz?: boolean }} */
	const meta = { hash, mtime: Bun.file(file).lastModified };
	if (precompress) {
		if (fs.existsSync(`${file}.br`)) meta.br = true;
		if (fs.existsSync(`${file}.gz`)) meta.gz = true;
	}

	return meta;
}

/** @param {string[]} files */
function validate_file_paths(files) {
	for (const file of files) {
		if (file.includes('*')) {
			throw new Error(
				`Cannot build with ${JSON.stringify(file)} because Bun treats literal \`*\` characters in route paths as wildcards. Rename the file or route to remove the \`*\` character.`
			);
		}
		// a leading ':' would need percent-encoding, but browsers request the colon raw
		if (file.split('/').some((segment) => segment.startsWith(':'))) {
			throw new Error(
				`Cannot build with ${JSON.stringify(file)} because Bun treats a route segment starting with \`:\` as a parameter. Rename the file or route so no segment starts with \`:\`.`
			);
		}
	}
}

/** @type {import('./index.js').default} */
export default function (opts = {}) {
	const {
		out = 'build',
		envPrefix = '',
		precompress = false,

View on GitHub (pinned to 03f1687fe6)

Solutions

Rename the route to avoid '*' — e.g. replace [...slug] with a fixed route or a named param [slug].
Check for accidentally created files/folders with '*' in their name inside src/routes.
Switch to an adapter without this restriction (e.g. adapter-node) if the wildcard route is required.

Example fix

// before
src/routes/[...slug]/+page.svelte
// after
src/routes/[slug]/+page.svelte  // or handle catch-alls with adapter-node

Defensive patterns

Strategy: validation

Validate before calling

import fs from 'node:fs';
import path from 'node:path';
const offenders = [];
(function walk(dir) {
  for (const f of fs.readdirSync(dir)) {
    const p = path.join(dir, f);
    if (fs.statSync(p).isDirectory()) walk(p);
    else if (p.includes('*')) offenders.push(p);
  }
})('src/routes');
if (offenders.length) throw new Error(`adapter-bun rejects '*' in route paths: ${offenders.join(', ')}`);

Type guard

const isBunSafeRoute = (file) => !file.includes('*');

Try / catch

try {
  await build();
} catch (e) {
  if (/Bun treats literal `\*` characters in route paths/.test(e.message)) {
    console.error('Rename the reported route file to remove the * character');
    process.exit(1);
  }
  throw e;
}

Prevention

Avoid SvelteKit rest routes ([...slug]) when targeting adapter-bun
Lint src/routes filenames for '*' before builds
Document adapter-bun route naming restrictions in the repo

When it happens

Trigger: validate_file_paths was called (from get_embed_entries, get_no_embed_entries, or create_routes) and one of the generated route file paths, e.g. 'src/routes/[...slug]/+page.svelte', contains a '*' character.

Common situations: Using SvelteKit rest parameters like [...slug] or catch-all routes with adapter-bun; nested optional rest routes like [[...rest]].

Related errors

AI-assisted analysis of sveltejs/kit@03f1687fe6 (2026-09-02). Data as JSON: /api/errors/b047ebb53ab7b986. Report an issue: GitHub.