diff --git a/packages/desktop/scripts/after-pack.js b/packages/desktop/scripts/after-pack.js
index ad92f7f5b..258393187 100644
--- a/packages/desktop/scripts/after-pack.js
+++ b/packages/desktop/scripts/after-pack.js
@@ -7,8 +7,125 @@ const WRAPPER_SCRIPT = `#!/bin/bash
 exec "$(dirname "$(readlink -f "$0")")/${EXECUTABLE_NAME}.bin" --no-sandbox "$@"
 `;
 
+// electron-builder arch enum → Node.js arch string
+const ARCH_MAP = { 0: "ia32", 1: "x64", 2: "armv7l", 3: "arm64", 4: "universal" };
+
+const RIPGREP_PLATFORM_DIR = {
+  darwin: { arm64: "arm64-darwin", x64: "x64-darwin" },
+  linux: { arm64: "arm64-linux", x64: "x64-linux" },
+  win32: { arm64: "arm64-win32", x64: "x64-win32" },
+};
+
+function rmSafe(target) {
+  fs.rmSync(target, { recursive: true, force: true });
+}
+
+function pruneChildrenExcept(parent, keep) {
+  if (!fs.existsSync(parent)) return;
+  for (const entry of fs.readdirSync(parent)) {
+    if (!keep.has(entry)) {
+      rmSafe(path.join(parent, entry));
+    }
+  }
+}
+
+function pruneOnnxRuntime(nodeModules, platform, arch) {
+  const onnxBin = path.join(nodeModules, "onnxruntime-node", "bin", "napi-v6");
+  if (!fs.existsSync(onnxBin)) return;
+
+  const otherPlatforms = ["darwin", "linux", "win32"].filter((p) => p !== platform);
+  for (const p of otherPlatforms) {
+    rmSafe(path.join(onnxBin, p));
+  }
+
+  pruneChildrenExcept(path.join(onnxBin, platform), new Set([arch]));
+
+  if (platform === "linux") {
+    const archDir = path.join(onnxBin, "linux", arch);
+    if (fs.existsSync(archDir)) {
+      for (const name of fs.readdirSync(archDir)) {
+        if (name.includes("cuda") || name.includes("tensorrt")) {
+          fs.rmSync(path.join(archDir, name), { force: true });
+        }
+      }
+    }
+  }
+}
+
+function pruneClaudeAgentSdk(nodeModules, platform, arch) {
+  const vendorRoot = path.join(nodeModules, "@anthropic-ai", "claude-agent-sdk", "vendor");
+  const keepName = RIPGREP_PLATFORM_DIR[platform]?.[arch];
+  if (!keepName) return;
+
+  pruneChildrenExcept(path.join(vendorRoot, "ripgrep"), new Set(["COPYING", keepName]));
+  pruneChildrenExcept(path.join(vendorRoot, "tree-sitter-bash"), new Set([keepName]));
+}
+
+function pruneNodePty(nodeModules, platform, arch) {
+  const prebuilds = path.join(nodeModules, "node-pty", "prebuilds");
+  pruneChildrenExcept(prebuilds, new Set([`${platform}-${arch}`]));
+
+  if (platform !== "win32") {
+    rmSafe(path.join(nodeModules, "node-pty", "third_party"));
+  }
+}
+
+function pruneSharpLibvips(nodeModules, platform, arch) {
+  const prefix = `sharp-libvips-${platform}-${arch}`;
+  const imgDir = path.join(nodeModules, "@img");
+  if (!fs.existsSync(imgDir)) return;
+
+  for (const entry of fs.readdirSync(imgDir)) {
+    if (entry.startsWith("sharp-") && entry !== prefix && !entry.startsWith(`sharp-${platform}-${arch}`)) {
+      rmSafe(path.join(imgDir, entry));
+    }
+  }
+}
+
+function pruneNativeModules(appOutDir, platform, arch) {
+  const resourcesDir =
+    platform === "darwin"
+      ? path.join(appOutDir, `${EXECUTABLE_NAME}.app`, "Contents", "Resources")
+      : path.join(appOutDir, "resources");
+
+  const nodeModules = path.join(resourcesDir, "app.asar.unpacked", "node_modules");
+  if (!fs.existsSync(nodeModules)) return;
+
+  const before = dirSizeSync(nodeModules);
+
+  pruneOnnxRuntime(nodeModules, platform, arch);
+  pruneClaudeAgentSdk(nodeModules, platform, arch);
+  pruneNodePty(nodeModules, platform, arch);
+  pruneSharpLibvips(nodeModules, platform, arch);
+
+  const after = dirSizeSync(nodeModules);
+  const savedMB = ((before - after) / 1024 / 1024).toFixed(1);
+  console.log(`Pruned native modules: ${savedMB} MB removed (${fmtMB(before)} → ${fmtMB(after)})`);
+}
+
+function dirSizeSync(dir) {
+  let total = 0;
+  for (const entry of fs.readdirSync(dir, { withFileTypes: true, recursive: true })) {
+    if (entry.isFile()) {
+      try {
+        total += fs.statSync(path.join(entry.parentPath || entry.path, entry.name)).size;
+      } catch {}
+    }
+  }
+  return total;
+}
+
+function fmtMB(bytes) {
+  return `${(bytes / 1024 / 1024).toFixed(1)} MB`;
+}
+
 exports.default = async function afterPack(context) {
-  if (context.electronPlatformName !== "linux") return;
+  const platform = context.electronPlatformName;
+  const arch = ARCH_MAP[context.arch] || process.arch;
+
+  pruneNativeModules(context.appOutDir, platform, arch);
+
+  if (platform !== "linux") return;
 
   const chromeSandbox = path.join(context.appOutDir, "chrome-sandbox");
   if (fs.existsSync(chromeSandbox)) {