Build profiles: HAL_FEATURES selects which features ship

build.js swaps src/features/index.js for a generated module importing
only the enabled features (gifts,swaps,ark,sp — unset means all,
"none" means a plain on-chain wallet), so excluded feature code and
its network endpoints never enter the bundle. Minimal profile:
476KB vs 577KB, with the Ark/gRPC, Boltz, and MuSig2 code verifiably
absent. `bun run build:minimal` builds it.

tools/minimal-smoke.js proves the minimal profile end-to-end: no
receive-mode dropdown, no gift button, no swap/Ark/SP settings cards,
no page errors, and a plain on-chain receive still lands. The two
blessed profiles are full (everything, the existing e2e suites) and
minimal (this smoke test); other combos should work but aren't CI'd.

Gift and SP primitives still live inside wallet.js, so those bytes
remain in the minimal bundle for now — extracting them is the next
step if we want the core leaner still.

Co-Authored-By: Claude Fable 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01QFAcD4V284DvYZZHP7Rxxy

1 files changed, 29 insertions, 1 deletions

diff --git a/build.js b/build.js
index 97744b1..8a0805b 100644
--- a/build.js
+++ b/build.js
@@ -136,11 +136,39 @@ export async function buildSpWorker({ minify = true } = {}) {
   return result.outputs[0].text();
 }
 
-export async function buildHtml({ minify = true, pwa = minify } = {}) {
+// Optional-feature selection: HAL_FEATURES is a comma list of enabled
+// features (gifts,swaps,ark,sp). Unset means all; "none"/"" means a minimal
+// on-chain-only wallet. A build plugin swaps src/features/index.js for a
+// generated module that only imports the enabled features, so a disabled
+// feature's code (and its network endpoints) never enters the bundle.
+const ALL_FEATURES = { gifts: 'giftsFeature', swaps: 'swapsFeature', ark: 'arkFeature', sp: 'spFeature' };
+
+export function enabledFeatures(spec = process.env.HAL_FEATURES) {
+  if (spec == null) return Object.keys(ALL_FEATURES);
+  return spec.split(',').map((x) => x.trim().toLowerCase()).filter((x) => x in ALL_FEATURES);
+}
+
+function featureIndexSource(enabled) {
+  return enabled.map((f) => `import { ${ALL_FEATURES[f]} } from './${f}.js';`).join('\n')
+    + `\nexport function buildFeatures(ctx) { return [${enabled.map((f) => `${ALL_FEATURES[f]}(ctx)`).join(', ')}]; }\n`;
+}
+
+const featurePlugin = (enabled) => ({
+  name: 'hal-features',
+  setup(b) {
+    b.onLoad({ filter: /src[\/\\]features[\/\\]index\.js$/ }, () => ({
+      contents: featureIndexSource(enabled),
+      loader: 'js',
+    }));
+  },
+});
+
+export async function buildHtml({ minify = true, pwa = minify, features = process.env.HAL_FEATURES } = {}) {
   const result = await Bun.build({
     entrypoints: ['./src/app.js'],
     target: 'browser',
     minify,
+    plugins: [featurePlugin(enabledFeatures(features))],
   });
   if (!result.success) {
     for (const log of result.logs) console.error(log);