diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..6185dca
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,109 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - "v*"
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: "Existing release tag to build and attach binaries to (for example v0.2.3)"
+        required: true
+  pull_request:
+    paths:
+      - ".github/workflows/release.yml"
+      - "Cargo.toml"
+      - "Cargo.lock"
+      - "package.json"
+      - "scripts/install.js"
+
+permissions:
+  contents: write
+
+env:
+  RELEASE_TAG: ${{ github.event_name == 'workflow_dispatch' && inputs.tag || github.ref_name }}
+
+jobs:
+  build:
+    name: Build ${{ matrix.asset }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-musl
+            asset: linux-x64
+          - os: ubuntu-24.04-arm
+            target: aarch64-unknown-linux-musl
+            asset: linux-arm64
+          - os: macos-14
+            target: aarch64-apple-darwin
+            asset: darwin-arm64
+          - os: macos-14
+            target: x86_64-apple-darwin
+            asset: darwin-x64
+
+    steps:
+      - name: Check out source
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event_name == 'workflow_dispatch' && inputs.tag || github.ref }}
+
+      - name: Install Rust toolchain and target
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: ${{ matrix.target }}
+
+      - name: Install musl toolchain
+        if: endsWith(matrix.target, '-linux-musl')
+        run: sudo apt-get update && sudo apt-get install --yes musl-tools
+
+      - name: Build release binary
+        shell: bash
+        run: |
+          target="${{ matrix.target }}"
+          if [[ "$target" == *-linux-musl ]]; then
+            # Bundled SQLite and ring compile C code; build it against musl too.
+            export "CC_${target//-/_}=musl-gcc"
+          fi
+          cargo build --release --locked --target "$target"
+          cp "target/${{ matrix.target }}/release/idx" "idx-${{ matrix.asset }}"
+          chmod 0755 "idx-${{ matrix.asset }}"
+
+      - name: Check binary runs
+        if: matrix.target != 'x86_64-apple-darwin'
+        run: ./idx-${{ matrix.asset }} --help >/dev/null
+
+      - name: Upload target artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: idx-${{ matrix.asset }}
+          path: idx-${{ matrix.asset }}
+          if-no-files-found: error
+
+  publish:
+    name: Attach binaries to release
+    needs: build
+    if: github.event_name != 'pull_request'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download target artifacts
+        uses: actions/download-artifact@v4
+        with:
+          pattern: idx-*
+          merge-multiple: true
+
+      - name: Write checksums
+        run: sha256sum idx-linux-x64 idx-linux-arm64 idx-darwin-arm64 idx-darwin-x64 > SHA256SUMS
+
+      - name: Attach binaries to the version tag
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ env.RELEASE_TAG }}
+          files: |
+            idx-linux-x64
+            idx-linux-arm64
+            idx-darwin-arm64
+            idx-darwin-x64
+            SHA256SUMS
diff --git a/.gitignore b/.gitignore
index 877d6f4..d7292fe 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,6 @@
 node_modules/
+/bin/
+*.tgz
 target/
 .direnv/
 .claude/
diff --git a/docs/NPM_DISTRIBUTION.md b/docs/NPM_DISTRIBUTION.md
new file mode 100644
index 0000000..dafcd12
--- /dev/null
+++ b/docs/NPM_DISTRIBUTION.md
@@ -0,0 +1,94 @@
+# npm distribution
+
+The npm package `idx-cli` is a small wrapper around the native `idx` binary.
+The package keeps the JavaScript launcher and postinstall downloader. The
+downloader selects a prebuilt GitHub Release asset for the current platform and
+places it at the path used by the `idx` bin entry.
+
+Supported release assets:
+
+| npm platform | Rust target | Release asset |
+| --- | --- | --- |
+| Linux x64 | `x86_64-unknown-linux-musl` | `idx-linux-x64` |
+| Linux arm64 | `aarch64-unknown-linux-musl` | `idx-linux-arm64` |
+| macOS arm64 | `aarch64-apple-darwin` | `idx-darwin-arm64` |
+| macOS x64 | `x86_64-apple-darwin` | `idx-darwin-x64` |
+
+The Linux binaries are statically linked against musl, so they do not depend
+on the host glibc version.
+
+Windows and other platform combinations are out of scope. The postinstall
+script reports the supported targets when it rejects a platform.
+
+## Use the package
+
+```bash
+npm install --global idx-cli
+idx --help
+
+# Or run the package without a global install.
+npx idx-cli --help
+```
+
+The package version and the release tag must match. For example, package
+version `0.2.3` downloads assets from the `v0.2.3` GitHub Release.
+
+The postinstall script downloads `SHA256SUMS` from the same release and
+refuses to install a binary whose checksum does not match.
+
+### pnpm and bun
+
+pnpm 10+ and bun do not run dependency lifecycle scripts by default, so the
+binary is never downloaded and `idx` reports that it is missing. Allow the
+postinstall script explicitly:
+
+```bash
+# pnpm
+pnpm add --global --allow-build=idx-cli idx-cli
+
+# bun
+bun add --global --trust idx-cli
+```
+
+Plain `npm install` and `npx` run the postinstall script normally.
+
+## Local smoke test
+
+The smoke script builds or reuses `target/release/idx`, packs the npm wrapper,
+installs the tarball into a new temporary directory, and runs the installed
+`idx` command. It uses `IDX_BINARY_URL` with a local `file:` URL, so the test
+does not need a registry publish or a network download.
+
+```bash
+nix develop -c bash -c 'scripts/npm-smoke.sh'
+nix develop -c bash -c 'npm pack --dry-run'
+```
+
+The `postinstall` script performs the release download for normal package
+installation. It skips the download when it runs inside this source checkout
+(where `Cargo.toml` exists) unless `IDX_BINARY_URL` is set. `IDX_BINARY_URL`
+accepts an HTTP(S) URL, a `file:` URL, or an existing local path for local
+testing. Set `IDX_BINARY_SHA256` to verify an override binary as well.
+
+## GitHub Release workflow
+
+Pushing a tag that matches `v*` starts
+`.github/workflows/release.yml`. The workflow builds all supported Rust
+targets, names the binaries with the asset names above, writes `SHA256SUMS`,
+and attaches everything to the matching GitHub Release. The asset names and
+URLs must stay aligned with `scripts/install.js`.
+
+To attach binaries to a tag that already exists, run the workflow manually:
+
+```bash
+gh workflow run release.yml -f tag=v0.2.3
+```
+
+Pull requests that touch the workflow or the installer run the build jobs
+without publishing, so target breakage shows up before a release.
+
+Release order:
+
+1. Push the tag, or run the workflow for an existing tag.
+2. Confirm the release has all binaries plus `SHA256SUMS`.
+3. Run `npm publish`.
diff --git a/flake.nix b/flake.nix
index b5f318f..ee09631 100644
--- a/flake.nix
+++ b/flake.nix
@@ -61,6 +61,7 @@
           inputsFrom = [ idxPackage ];
           packages = with pkgs; [
             rustToolchain
+            nodejs_22
             cargo-watch
             cargo-nextest
             prek
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..ceff396
--- /dev/null
+++ b/package.json
@@ -0,0 +1,32 @@
+{
+  "name": "idx-cli",
+  "version": "0.2.3",
+  "description": "CLI tool for Indonesian stock market (IDX) analysis",
+  "license": "MIT",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/0xrsydn/idx-cli.git"
+  },
+  "homepage": "https://github.com/0xrsydn/idx-cli",
+  "keywords": [
+    "idx",
+    "stocks",
+    "indonesia",
+    "finance",
+    "cli"
+  ],
+  "engines": {
+    "node": ">=16"
+  },
+  "bin": {
+    "idx": "./scripts/idx.js"
+  },
+  "files": [
+    "scripts/idx.js",
+    "scripts/install.js"
+  ],
+  "scripts": {
+    "postinstall": "node scripts/install.js",
+    "smoke": "bash scripts/npm-smoke.sh"
+  }
+}
diff --git a/scripts/idx.js b/scripts/idx.js
new file mode 100755
index 0000000..42cbc8d
--- /dev/null
+++ b/scripts/idx.js
@@ -0,0 +1,39 @@
+#!/usr/bin/env node
+"use strict";
+
+const fs = require("node:fs");
+const path = require("node:path");
+const { spawn } = require("node:child_process");
+
+const binaryName = process.platform === "win32" ? "idx.exe" : "idx";
+const binaryPath = path.join(__dirname, "..", "bin", binaryName);
+
+if (!fs.existsSync(binaryPath)) {
+  console.error(`idx-cli: installed binary not found at ${binaryPath}`);
+  console.error("idx-cli: rerun npm install or set IDX_BINARY_URL for a local binary");
+  process.exit(1);
+}
+
+const child = spawn(binaryPath, process.argv.slice(2), { stdio: "inherit" });
+
+// Pass termination signals from a supervisor (kill, docker stop) to the binary.
+for (const signal of ["SIGTERM", "SIGHUP"]) {
+  process.on(signal, () => child.kill(signal));
+}
+// Ctrl+C already reaches the binary through the terminal's process group.
+process.on("SIGINT", () => {});
+
+child.once("error", (error) => {
+  console.error(`idx-cli: failed to start ${binaryPath}: ${error.message}`);
+  process.exit(1);
+});
+
+child.once("exit", (code, signal) => {
+  if (signal) {
+    process.removeAllListeners(signal);
+    process.kill(process.pid, signal);
+    return;
+  }
+
+  process.exit(code === null ? 1 : code);
+});
diff --git a/scripts/install.js b/scripts/install.js
new file mode 100755
index 0000000..ececbaf
--- /dev/null
+++ b/scripts/install.js
@@ -0,0 +1,262 @@
+#!/usr/bin/env node
+"use strict";
+
+const crypto = require("node:crypto");
+const fs = require("node:fs");
+const http = require("node:http");
+const https = require("node:https");
+const path = require("node:path");
+const { pipeline } = require("node:stream");
+const { URL, fileURLToPath } = require("node:url");
+
+const packageRoot = path.resolve(__dirname, "..");
+const packageManifest = JSON.parse(
+  fs.readFileSync(path.join(packageRoot, "package.json"), "utf8"),
+);
+const binaryName = process.platform === "win32" ? "idx.exe" : "idx";
+const binaryDirectory = path.join(packageRoot, "bin");
+const binaryPath = path.join(binaryDirectory, binaryName);
+const githubRepository = "0xrsydn/idx-cli";
+const maxRedirects = 5;
+const requestTimeoutMs = 60_000;
+
+const targets = {
+  "linux/x64": {
+    label: "linux-x64",
+    triple: "x86_64-unknown-linux-gnu",
+    asset: "idx-linux-x64",
+  },
+  "linux/arm64": {
+    label: "linux-arm64",
+    triple: "aarch64-unknown-linux-gnu",
+    asset: "idx-linux-arm64",
+  },
+  "darwin/arm64": {
+    label: "darwin-arm64",
+    triple: "aarch64-apple-darwin",
+    asset: "idx-darwin-arm64",
+  },
+  "darwin/x64": {
+    label: "darwin-x64",
+    triple: "x86_64-apple-darwin",
+    asset: "idx-darwin-x64",
+  },
+};
+
+function currentTarget() {
+  const key = `${process.platform}/${process.arch}`;
+  const target = targets[key];
+  if (!target) {
+    const supported = Object.values(targets)
+      .map(({ label, triple }) => `${label} (${triple})`)
+      .join(", ");
+    throw new Error(
+      `unsupported platform ${key}; supported targets are ${supported}`,
+    );
+  }
+  return target;
+}
+
+function releaseAssetUrl(assetName) {
+  return `https://github.com/${githubRepository}/releases/download/v${packageManifest.version}/${assetName}`;
+}
+
+function ensureBinaryDirectory() {
+  fs.mkdirSync(binaryDirectory, { recursive: true });
+}
+
+function temporaryBinaryPath() {
+  return `${binaryPath}.${process.pid}.tmp`;
+}
+
+function replaceWithLocalBinary(sourcePath) {
+  const resolvedSource = path.resolve(sourcePath);
+  const sourceStat = fs.statSync(resolvedSource, { throwIfNoEntry: false });
+  if (!sourceStat || !sourceStat.isFile()) {
+    throw new Error(`local binary does not exist or is not a file: ${resolvedSource}`);
+  }
+
+  const temporaryPath = temporaryBinaryPath();
+  try {
+    fs.copyFileSync(resolvedSource, temporaryPath);
+    fs.chmodSync(temporaryPath, 0o755);
+    fs.renameSync(temporaryPath, binaryPath);
+  } finally {
+    if (fs.existsSync(temporaryPath)) {
+      fs.unlinkSync(temporaryPath);
+    }
+  }
+}
+
+function request(url, onResponse, redirects = 0) {
+  if (redirects > maxRedirects) {
+    return Promise.reject(new Error(`too many redirects while downloading ${url}`));
+  }
+
+  let parsedUrl;
+  try {
+    parsedUrl = new URL(url);
+  } catch (error) {
+    return Promise.reject(new Error(`invalid download URL: ${error.message}`));
+  }
+
+  if (!["http:", "https:"].includes(parsedUrl.protocol)) {
+    return Promise.reject(new Error(`unsupported download protocol: ${parsedUrl.protocol}`));
+  }
+
+  const client = parsedUrl.protocol === "https:" ? https : http;
+  return new Promise((resolve, reject) => {
+    const req = client.get(
+      parsedUrl,
+      {
+        headers: {
+          Accept: "application/octet-stream",
+          "User-Agent": `idx-cli-npm/${packageManifest.version}`,
+        },
+      },
+      (response) => {
+        const status = response.statusCode || 0;
+        if (status >= 300 && status < 400 && response.headers.location) {
+          const redirectedUrl = new URL(response.headers.location, parsedUrl).toString();
+          response.resume();
+          request(redirectedUrl, onResponse, redirects + 1).then(resolve, reject);
+          return;
+        }
+
+        if (status !== 200) {
+          response.resume();
+          reject(new Error(`download failed with HTTP ${status} for ${url}`));
+          return;
+        }
+
+        onResponse(response).then(resolve, reject);
+      },
+    );
+    req.setTimeout(requestTimeoutMs, () => {
+      req.destroy(new Error(`timed out after ${requestTimeoutMs / 1000}s downloading ${url}`));
+    });
+    req.once("error", reject);
+  });
+}
+
+function download(url, destination) {
+  return request(
+    url,
+    (response) =>
+      new Promise((resolve, reject) => {
+        const output = fs.createWriteStream(destination, { mode: 0o755 });
+        pipeline(response, output, (error) => (error ? reject(error) : resolve()));
+      }),
+  );
+}
+
+function downloadText(url) {
+  return request(
+    url,
+    (response) =>
+      new Promise((resolve, reject) => {
+        const chunks = [];
+        response.on("data", (chunk) => chunks.push(chunk));
+        response.once("end", () => resolve(Buffer.concat(chunks).toString("utf8")));
+        response.once("error", reject);
+      }),
+  );
+}
+
+function sha256File(filePath) {
+  return crypto.createHash("sha256").update(fs.readFileSync(filePath)).digest("hex");
+}
+
+async function expectedReleaseChecksum(assetName) {
+  const sums = await downloadText(releaseAssetUrl("SHA256SUMS"));
+  for (const line of sums.split(/\r?\n/)) {
+    const [hash, name] = line.trim().split(/\s+\*?/);
+    if (name === assetName && /^[0-9a-f]{64}$/i.test(hash)) {
+      return hash.toLowerCase();
+    }
+  }
+  throw new Error(`SHA256SUMS for v${packageManifest.version} has no entry for ${assetName}`);
+}
+
+function verifyChecksum(filePath, expected, label) {
+  const actual = sha256File(filePath);
+  if (actual !== expected.toLowerCase()) {
+    throw new Error(`checksum mismatch for ${label}: expected ${expected}, got ${actual}`);
+  }
+}
+
+async function replaceWithDownloadedBinary(url, expectedSha256) {
+  const temporaryPath = temporaryBinaryPath();
+  try {
+    await download(url, temporaryPath);
+    if (expectedSha256) {
+      verifyChecksum(temporaryPath, expectedSha256, url);
+    }
+    fs.chmodSync(temporaryPath, 0o755);
+    fs.renameSync(temporaryPath, binaryPath);
+  } finally {
+    if (fs.existsSync(temporaryPath)) {
+      fs.unlinkSync(temporaryPath);
+    }
+  }
+}
+
+function localPathFromOverride(value) {
+  if (value.startsWith("file:")) {
+    const parsedUrl = new URL(value);
+    if (parsedUrl.protocol !== "file:") {
+      throw new Error(`unsupported local URL protocol: ${parsedUrl.protocol}`);
+    }
+    return fileURLToPath(parsedUrl);
+  }
+
+  if (!/^[a-z][a-z\d+.-]*:\/\//i.test(value)) {
+    const candidate = path.resolve(value);
+    if (fs.existsSync(candidate)) {
+      return candidate;
+    }
+  }
+
+  return null;
+}
+
+async function main() {
+  const override = process.env.IDX_BINARY_URL;
+  const overrideSha256 = process.env.IDX_BINARY_SHA256;
+
+  // `npm install` inside the Rust checkout should not fetch a release binary.
+  if (!override && fs.existsSync(path.join(packageRoot, "Cargo.toml"))) {
+    console.log("idx-cli: source checkout detected; skipping binary download (set IDX_BINARY_URL to override)");
+    return;
+  }
+
+  const target = currentTarget();
+  const source = override || releaseAssetUrl(target.asset);
+
+  ensureBinaryDirectory();
+  if (override) {
+    const localPath = localPathFromOverride(override);
+    if (localPath) {
+      if (overrideSha256) {
+        verifyChecksum(localPath, overrideSha256, localPath);
+      }
+      replaceWithLocalBinary(localPath);
+      console.log(`idx-cli: installed local binary from ${path.resolve(localPath)}`);
+      return;
+    }
+    console.log(`idx-cli: downloading binary from IDX_BINARY_URL (${override})`);
+  } else {
+    console.log(`idx-cli: downloading ${target.asset} for ${target.label} from ${source}`);
+  }
+
+  const expectedSha256 = override
+    ? overrideSha256
+    : await expectedReleaseChecksum(target.asset);
+  await replaceWithDownloadedBinary(source, expectedSha256);
+  console.log(`idx-cli: installed binary at ${binaryPath}`);
+}
+
+main().catch((error) => {
+  console.error(`idx-cli: ${error.message}`);
+  process.exit(1);
+});
diff --git a/scripts/npm-smoke.sh b/scripts/npm-smoke.sh
new file mode 100755
index 0000000..e6b58ac
--- /dev/null
+++ b/scripts/npm-smoke.sh
@@ -0,0 +1,74 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+smoke_dir="$(mktemp -d "${TMPDIR:-/tmp}/idx-cli-npm-smoke.XXXXXX")"
+install_dir="${smoke_dir}/install"
+npm_cache="${smoke_dir}/npm-cache"
+
+cleanup() {
+  rm -rf "$smoke_dir"
+}
+
+on_error() {
+  local status=$?
+  echo "npm smoke: FAILED on line ${BASH_LINENO[0]} (status ${status})" >&2
+  exit "$status"
+}
+
+trap cleanup EXIT
+trap on_error ERR
+
+cd "$repo_root"
+
+release_binary="${repo_root}/target/release/idx"
+if [[ -x "$release_binary" ]]; then
+  echo "npm smoke: reusing ${release_binary}"
+else
+  echo "npm smoke: building ${release_binary}"
+  cargo build --release --locked
+fi
+
+if [[ ! -x "$release_binary" ]]; then
+  echo "npm smoke: release binary was not produced at ${release_binary}" >&2
+  exit 1
+fi
+
+echo "npm smoke: packing wrapper"
+mkdir -p "$npm_cache"
+tarball_name="$(npm_config_cache="$npm_cache" npm pack --silent --pack-destination "$smoke_dir" | tail -n 1)"
+tarball="${smoke_dir}/${tarball_name}"
+if [[ -z "$tarball_name" || ! -f "$tarball" ]]; then
+  echo "npm smoke: expected tarball was not produced at ${tarball}" >&2
+  exit 1
+fi
+
+mkdir -p "$install_dir"
+binary_url="$(node -e 'const { pathToFileURL } = require("node:url"); process.stdout.write(pathToFileURL(process.argv[1]).href)' "$release_binary")"
+echo "npm smoke: installing tarball into ${install_dir}"
+npm_config_cache="$npm_cache" IDX_BINARY_URL="$binary_url" npm install \
+  --prefix "$install_dir" \
+  "$tarball" \
+  --no-save \
+  --no-package-lock \
+  --no-audit \
+  --no-fund \
+  --foreground-scripts
+
+resolved_bin="${install_dir}/node_modules/.bin/idx"
+if [[ ! -x "$resolved_bin" ]]; then
+  echo "npm smoke: npm did not create an executable bin link at ${resolved_bin}" >&2
+  exit 1
+fi
+
+help_output="${smoke_dir}/help.txt"
+echo "npm smoke: running installed idx --help"
+"$resolved_bin" --help | tee "$help_output"
+if ! grep -q "Usage: idx" "$help_output"; then
+  echo "npm smoke: --help output did not contain the expected usage line" >&2
+  exit 1
+fi
+
+echo "npm smoke: running installed idx config --help"
+"$resolved_bin" config --help
+echo "npm smoke: PASS (pack, install, --help, and config --help)"