diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index be5a8f3d5..62cfc8b46 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -60,8 +60,8 @@ jobs:
           DEVSPACE_REQUIRE_PI_SANDBOX: ${{ matrix.os == 'ubuntu-latest' && '1' || '0' }}
         run: pnpm test
 
-      - name: Build
-        run: pnpm build
+      - name: Package install smoke test
+        run: pnpm test:package-install
 
       - name: Doctor
         run: node dist/cli.js doctor
diff --git a/bin/devspace-agentd.js b/bin/devspace-agentd.js
index 268c36097..e6c54ca1b 100755
--- a/bin/devspace-agentd.js
+++ b/bin/devspace-agentd.js
@@ -1,2 +1,4 @@
 #!/usr/bin/env node
-import "../dist/local-agent-daemon-main.js";
+import { runEntrypoint } from "./run-entrypoint.js";
+
+await runEntrypoint("../src/local-agent-daemon-main.ts", "../dist/local-agent-daemon-main.js");
diff --git a/bin/devspace.js b/bin/devspace.js
index 8fb127218..4e4788a1b 100755
--- a/bin/devspace.js
+++ b/bin/devspace.js
@@ -1,2 +1,4 @@
 #!/usr/bin/env node
-import "../dist/cli.js";
+import { runEntrypoint } from "./run-entrypoint.js";
+
+await runEntrypoint("../src/cli.ts", "../dist/cli.js");
diff --git a/bin/run-entrypoint.js b/bin/run-entrypoint.js
new file mode 100644
index 000000000..f32983a1c
--- /dev/null
+++ b/bin/run-entrypoint.js
@@ -0,0 +1,20 @@
+import { existsSync } from "node:fs";
+import { fileURLToPath } from "node:url";
+
+export async function runEntrypoint(sourcePath, distPath) {
+  const sourceUrl = new URL(sourcePath, import.meta.url);
+  if (existsSync(fileURLToPath(sourceUrl))) {
+    try {
+      await import("tsx/esm");
+    } catch (error) {
+      throw new Error(
+        "DevSpace source checkout detected, but tsx is unavailable. Run `pnpm install` in the checkout; refusing to fall back to potentially stale dist output.",
+        { cause: error },
+      );
+    }
+    await import(sourceUrl.href);
+    return;
+  }
+
+  await import(new URL(distPath, import.meta.url).href);
+}
diff --git a/package.json b/package.json
index 9a4c2a83a..1835ba80d 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,7 @@
     "schema:config": "tsx scripts/generate-config-schema.ts",
     "start": "node dist/cli.js serve",
     "test": "tsx --test --test-concurrency=1 \"src/**/*.test.ts\"",
+    "test:package-install": "tsx --test --test-concurrency=1 \"test/package-install-smoke.test.ts\"",
     "typecheck": "tsc -p tsconfig.json --noEmit"
   },
   "keywords": [],
diff --git a/src/bin-launcher.test.ts b/src/bin-launcher.test.ts
new file mode 100644
index 000000000..00b43a99f
--- /dev/null
+++ b/src/bin-launcher.test.ts
@@ -0,0 +1,89 @@
+import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
+import { cpSync, mkdirSync, mkdtempSync, rmSync, symlinkSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { writeTestDevspaceConfig } from "./test-support/config.test.js";
+
+const projectRoot = fileURLToPath(new URL("..", import.meta.url));
+const tsxRoot = join(projectRoot, "node_modules", "tsx");
+
+for (const entrypoint of [
+  {
+    bin: "devspace.js",
+    source: "src/cli.ts",
+    dist: "dist/cli.js",
+  },
+  {
+    bin: "devspace-agentd.js",
+    source: "src/local-agent-daemon-main.ts",
+    dist: "dist/local-agent-daemon-main.js",
+  },
+]) {
+  testLauncher(entrypoint);
+}
+
+testLinkedCheckoutReadsCurrentConfig();
+testMissingSourceRuntimeFailsClosed();
+
+function testLinkedCheckoutReadsCurrentConfig(): void {
+  const root = mkdtempSync(join(tmpdir(), "devspace-bin-config-test-"));
+  try {
+    const env = writeTestDevspaceConfig(root, { tools: { mode: "codex" } });
+    const output = execFileSync(process.execPath, [join(projectRoot, "bin", "devspace.js"), "config", "get"], {
+      encoding: "utf8",
+      env: { ...process.env, ...env },
+    });
+    const config = JSON.parse(output) as { tools?: { mode?: string } };
+    assert.equal(config.tools?.mode, "codex");
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+}
+
+function testMissingSourceRuntimeFailsClosed(): void {
+  const root = mkdtempSync(join(tmpdir(), "devspace-bin-missing-tsx-test-"));
+  try {
+    cpSync(join(projectRoot, "bin"), join(root, "bin"), { recursive: true });
+    mkdirSync(join(root, "src"), { recursive: true });
+    mkdirSync(join(root, "dist"), { recursive: true });
+    writeFileSync(join(root, "package.json"), JSON.stringify({ type: "module" }));
+    writeFileSync(join(root, "src", "cli.ts"), 'console.log("source");\n');
+    writeFileSync(join(root, "dist", "cli.js"), 'console.log("stale-dist");\n');
+
+    assert.throws(
+      () => execFileSync(process.execPath, [join(root, "bin", "devspace.js")], { encoding: "utf8", stdio: "pipe" }),
+      /source checkout.*tsx.*pnpm install/is,
+    );
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+}
+
+function testLauncher(entrypoint: { bin: string; source: string; dist: string }): void {
+  const root = mkdtempSync(join(tmpdir(), "devspace-bin-launcher-test-"));
+  try {
+    cpSync(join(projectRoot, "bin"), join(root, "bin"), { recursive: true });
+    mkdirSync(dirname(join(root, entrypoint.source)), { recursive: true });
+    mkdirSync(dirname(join(root, entrypoint.dist)), { recursive: true });
+    mkdirSync(join(root, "node_modules"), { recursive: true });
+    symlinkSync(tsxRoot, join(root, "node_modules", "tsx"), process.platform === "win32" ? "junction" : "dir");
+    writeFileSync(join(root, "package.json"), JSON.stringify({ type: "module" }));
+    writeFileSync(join(root, entrypoint.source), 'console.log("source");\n');
+    writeFileSync(join(root, entrypoint.dist), 'console.log("dist");\n');
+
+    const sourceOutput = execFileSync(process.execPath, [join(root, "bin", entrypoint.bin)], {
+      encoding: "utf8",
+    }).trim();
+    assert.equal(sourceOutput, "source", `${entrypoint.bin} must prefer source in a linked checkout`);
+
+    rmSync(join(root, entrypoint.source));
+    const packagedOutput = execFileSync(process.execPath, [join(root, "bin", entrypoint.bin)], {
+      encoding: "utf8",
+    }).trim();
+    assert.equal(packagedOutput, "dist", `${entrypoint.bin} must use dist in a published package`);
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+}
diff --git a/test/package-install-smoke.test.ts b/test/package-install-smoke.test.ts
new file mode 100644
index 000000000..c53477fd8
--- /dev/null
+++ b/test/package-install-smoke.test.ts
@@ -0,0 +1,88 @@
+import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
+import { mkdirSync, mkdtempSync, readdirSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { writeTestDevspaceConfig } from "../src/test-support/config.test.js";
+
+const projectRoot = fileURLToPath(new URL("..", import.meta.url));
+
+testPackedPackageLaunchers();
+
+function testPackedPackageLaunchers(): void {
+  const root = mkdtempSync(join(tmpdir(), "devspace-packed-bin-test-"));
+  const installRoot = join(root, "install");
+  try {
+    mkdirSync(installRoot, { recursive: true });
+    execFileSync(npmExecutable(), ["pack", "--silent", "--pack-destination", root], {
+      cwd: projectRoot,
+      encoding: "utf8",
+      stdio: "pipe",
+      shell: process.platform === "win32",
+    });
+    const archive = readdirSync(root).find((name) => name.endsWith(".tgz"));
+    assert.ok(archive, "npm pack must produce a package archive");
+
+    execFileSync(npmExecutable(), [
+      "install",
+      "--no-audit",
+      "--no-fund",
+      "--no-package-lock",
+      "--no-save",
+      "--omit=optional",
+      join(root, archive),
+    ], {
+      cwd: installRoot,
+      encoding: "utf8",
+      stdio: "pipe",
+      shell: process.platform === "win32",
+    });
+
+    const configRoot = join(root, "config");
+    const env = writeTestDevspaceConfig(configRoot, {
+      storage: { stateDir: join(root, "state") },
+      workspaces: { allowedRoots: [root], worktreeRoot: join(root, "worktrees") },
+      skills: { agentDir: join(root, "agents") },
+    });
+    const cliOutput = execInstalledBin(installRoot, "devspace", ["config", "get"], {
+      ...process.env,
+      ...env,
+    });
+    const config = JSON.parse(cliOutput) as { tools?: { mode?: string } };
+    assert.equal(config.tools?.mode, "codex");
+
+    execInstalledBin(installRoot, "devspace-agentd", [], {
+      ...process.env,
+      ...env,
+      DEVSPACE_AGENTD_IDLE_TIMEOUT_MS: "0",
+      DEVSPACE_AGENTD_SHUTDOWN_TIMEOUT_MS: "1000",
+    });
+  } finally {
+    rmSync(root, { recursive: true, force: true });
+  }
+}
+
+function npmExecutable(): string {
+  return process.platform === "win32" ? "npm.cmd" : "npm";
+}
+
+function execInstalledBin(
+  installRoot: string,
+  name: string,
+  args: string[],
+  env: NodeJS.ProcessEnv,
+): string {
+  const executable = join(
+    installRoot,
+    "node_modules",
+    ".bin",
+    process.platform === "win32" ? `${name}.cmd` : name,
+  );
+  return execFileSync(executable, args, {
+    encoding: "utf8",
+    env,
+    stdio: "pipe",
+    shell: process.platform === "win32",
+  });
+}