initial

tsup.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from 'tsup';
+
+export default defineConfig({
+  entry: { index: 'src/index.ts' },
+  format: ['esm', 'cjs'],
+  dts: true,
+  clean: true,
+  treeshake: true,
+  sourcemap: true,
+  // react/react-dom come from the host app; radix-ui + phosphor are
+  // declared dependencies and are externalized automatically by tsup.
+  external: ['react', 'react-dom'],
+});