Peephole

Preview a GitHub repository before you clone it.

**Preview a GitHub repository before you clone it.** Peephole helps you understand public GitHub repositories, explore their structure, and run supported applications directly from your browser — without cloning or configuring them locally. ### Explore repositories Open a public GitHub repository and select Peephole from the repository header. The Chrome Side Panel provides: - Framework, package manager, and runtime detection - Repository structure and frontend/backend project discovery - Dependency and environment requirement analysis - Confirmed GitHub deployment information - Preview compatibility and supported project selection - GitHub Light, Dark, and Dark Dimmed theme integration Choose a public branch, and Peephole resolves it to an exact commit before analysis or preview. ### Static Preview Build and explore supported frontend applications in an isolated, resource-limited gVisor sandbox. Supported projects include: - Static HTML websites - Vite + React applications using npm - Supported nested frontend projects with their own lockfiles Open the generated preview through a separate HTTPS address. You can close and reopen the preview without rebuilding it. ### Full-stack Preview — New in v0.3.0 Preview supported frontend and backend applications together. Peephole can detect compatible projects within a repository and run: - Vite + React frontends using npm - Express backends using Node.js and npm - Frontend-to-backend communication through `/api` routes - Temporary PostgreSQL databases for eligible backend projects Full-stack previews run in isolated environments and can be stopped directly from the Side Panel. ### Environment Configuration — New in v0.3.0 Some applications require configuration before they can run. Peephole detects declared environment variable names and lets you provide supported, non-sensitive configuration values, such as display messages or feature settings. Sensitive values, including API keys, passwords, and tokens, are not supported. User-provided configuration is accessible to the previewed application's backend and must not contain confidential information. ### Privacy and Security Peephole works with public GitHub repositories only. GitHub App OAuth verifies your identity before creating preview jobs. You do not need to generate or provide a GitHub personal access token. Preview environments are isolated and resource-limited. Preview URLs may be accessible to anyone who possesses the link. Peephole does not include analytics or advertising SDKs. ### Current Limitations Preview execution supports specific project configurations, not arbitrary repositories. Frameworks such as Vue, Svelte, and Next.js are not currently supported for executable previews. Full-stack execution is limited to supported Vite + React and Express combinations. External API credentials, general outbound backend network access, and arbitrary backend execution are not supported. **Source code and documentation:** https://github.com/The-peephole/peephole