diff --git a/src/cli/program.ts b/src/cli/program.ts
index a0c6537..9c24504 100644
--- a/src/cli/program.ts
+++ b/src/cli/program.ts
@@ -1,4 +1,7 @@
-import { calculate_coverage, type Coverage, type CoverageResult } from '../lib/index.js'
+// import from absolute package name instead of relative import (like ../lib/index.ts)
+// to prevent lib/index.js being bundled into cli.js, which would mean that indexjs
+// ends up in our /dist twice which is wasteful
+import { calculate_coverage, type Coverage, type CoverageResult } from '@projectwallace/css-code-coverage'
 
 export type Report = {
 	context: {
diff --git a/tsconfig.json b/tsconfig.json
index d6d0a9b..a84a797 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -18,7 +18,11 @@
 		],
 		"declaration": true,
 		"rootDirs": ["src/lib", "src/cli"],
-		"outDir": "dist"
+		"outDir": "dist",
+		"paths": {
+			// So we can import like an external in the CLI
+			"@projectwallace/css-code-coverage": ["./src/lib/index.ts"]
+		}
 	},
 	"include": [
 		"src/lib/index.ts",
diff --git a/tsdown.config.ts b/tsdown.config.ts
index 017ef18..52e545d 100644
--- a/tsdown.config.ts
+++ b/tsdown.config.ts
@@ -20,6 +20,9 @@ export default defineConfig([
 		platform: 'node',
 		format: 'esm',
 		dts: false,
+		// The CLI references the Core via 'external' reference to prevent it
+		// from ending up as duplicate code in cli.js
+		external: ['@projectwallace/css-code-coverage'],
 		plugins: [
 			codecovVitePlugin({
 				enableBundleAnalysis: process.env.CODECOV_TOKEN !== undefined,