[korvin89]

Since 2.22.1 (#108) the build generates esm/package.json with only version and type. esbuild reads sideEffects from the nearest package.json, so it no longer sees the root "sideEffects": false and keeps every icon module in esm/. Each one leaves its import * as React from 'react' in the bundle.

Only esbuild is affected. Vite 7 (Rollup) and webpack 5 already keep a single module.

Fix: repeat the root field in the generated file, as uikit does in its gulpfile:

JSON.stringify({version: pkg.version, type: 'module', sideEffects: pkg.sideEffects})

Numbers

esbuild 0.25.12, import {ArrowRotateLeft} from '@gravity-ui/icons', bundle, minify, format: 'esm', external: ['react']. Icon modules counted with bytesInOutput > 0 in metafile.outputs:

	Icon modules in output	Minified	Brotli
2.23.0 (npm)	809	20.6 kB	1.04 kB
This branch	1	0.45 kB	0.26 kB

Verification

• npm run build: esm/package.json is {"version":"2.23.0","type":"module","sideEffects":false}. Root package.json and the CJS output are byte-identical to a build of main. esm/package.json is the only file in esm/ that changes.
• npm run lint, npm run typecheck: pass.
• npm pack --dry-run: esm/package.json is included.
• esbuild before/after as above. Before used the published 2.23.0 tarball, after used this branch's build.

[gravity-ui]

Preview is ready.