# no-telemetry

> A CLI tool that detects telemetry in JS/TS dependencies and disables it in one command by writing opt-out environment variables to a dotenv file.

no-telemetry is an open-source CLI tool built by apvarun that scans a JavaScript or TypeScript project's `package.json`, identifies dependencies that collect telemetry, and writes the appropriate opt-out environment variables to a `.env` file in a single command. It is released under the MIT license, has zero production dependencies, and makes no runtime network requests — including no telemetry of its own.

## What It Is

no-telemetry is a developer privacy and policy enforcement tool for Node.js projects. It maintains a curated registry of JS/TS libraries that collect telemetry and the documented environment variables used to disable that collection. Running `npx no-telemetry init -y` matches the current project's direct dependencies against the registry and writes the correct opt-out variables to `.env`, including the cross-tool `DO_NOT_TRACK=1` convention. The `doctor` command prints a per-tool status table, and `check` exits with code `1` if any installed library still has telemetry enabled — making it suitable for CI enforcement.

## Registry Coverage and Supported Tools

The bundled registry covers 43 tools as of v0.2.0, including:

- **34** documented environment-variable opt-outs (e.g., `NEXT_TELEMETRY_DISABLED=1`, `TURBO_TELEMETRY_DISABLED=1`, `CHECKPOINT_DISABLE=1`)
- **2** opt-in checks (telemetry off by default)
- **7** config-only tools detected and reported but not modified

Named tools in the registry include Next.js, Prisma, Vercel CLI, Turborepo, Storybook, Expo, Wrangler, Supabase CLI, GitHub CLI, and Claude Code. The `list` and `why <id>` commands expose the full registry without requiring a project.

## How It Works

1. Reads `dependencies` and `devDependencies` from the current directory's `package.json`.
2. Matches direct dependencies against the bundled registry (no network fetch at runtime).
3. Adds missing opt-out variables to `.env` (or a custom target path) in a marker-delimited block.
4. Resolves effective values from the process environment, `.env.local`, and `.env` in that precedence order.

Key safety properties: it never overwrites a non-empty value, never edits shell profiles or `package.json`, fills empty `KEY=` placeholders in place, and is fully idempotent on re-runs. Workspace scanning and transitive dependency scanning are explicitly out of scope.

## CI Integration

no-telemetry is designed to be pinned and run in CI pipelines. The `check` command exits `1` on policy failure, making it a drop-in gate:

```
npx --yes no-telemetry@0.2.0 check --json=compact
```

All commands support `--json` and `--json=compact` for structured output suitable for pipes and automation. The `--dry-run` flag on `init` previews changes without writing files, and `--target stdout` sends pure `KEY=VALUE` lines to stdout for scripting.

## Programmatic API

Beyond the CLI, no-telemetry exposes a stable ESM-only programmatic API for Node.js 18+. Key exports include `scan`, `planInit`, `applyInit`, `failsCheck`, `buildReport`, and `REGISTRY`. `LibraryResult.status` uses machine-stable tokens (`disabled`, `enabled`, `not_applicable`, `not_found`, `unsupported`) for reliable downstream processing.

## Update: v0.2.0

The latest release is v0.2.0, published on 2026-08-22. The project was created on 2026-08-19, making this an early-stage but actively developed tool. The repository is TypeScript-first, tested on Node.js 18, 20, and 22, and uses pnpm. An agent skill definition is also included in the repository under `skills/no-telemetry/SKILL.md`, signaling intent for use in agentic workflows.

## Features
- Detect telemetry in JS/TS dependencies by scanning package.json
- Write opt-out environment variables to .env in one command
- Curated registry of 43 tools with documented opt-out variables
- CI-friendly check command with exit code 1 on policy failure
- Dry-run mode to preview changes before writing
- Idempotent init — safe to re-run without overwriting existing values
- Structured JSON output for pipes and automation
- Programmatic ESM API for Node.js 18+
- Zero production dependencies and no runtime network requests
- Supports DO_NOT_TRACK=1 convention alongside tool-specific variables
- doctor command prints per-tool status table
- why command explains registry entry for a specific tool
- list command dumps full registry without requiring a project
- Custom target file support including stdout mode
- Supports opt-out, opt-in, and unsupported registry entry kinds

## Integrations
Next.js, Prisma, Vercel CLI, Turborepo, Storybook, Expo, Wrangler, Supabase CLI, GitHub CLI, Claude Code, Railway, DO_NOT_TRACK convention

## Platforms
CLI, API

## Pricing
Open Source

## Version
v0.2.0

## Links
- Website: https://github.com/apvarun/no-telemetry
- Documentation: https://github.com/apvarun/no-telemetry#readme
- Repository: https://github.com/apvarun/no-telemetry
- EveryDev.ai: https://www.everydev.ai/tools/no-telemetry