Deploy and Host OpenPencil on Railway

OpenPencil is an open-source AI-assisted vector design tool. This template gives you a private browser workspace for editing designs and working with supported API-key AI agents. It packages the Rust web host from OpenPencil v0.8.4, an upstream prerelease.

About Hosting OpenPencil

The template deploys two services: a password-protected public gateway and a private OpenPencil application with a persistent volume. No database or GPU is required. Railway generates the access password and wires the private upstream address and public origin.

Open the gateway domain and sign in as admin using its ACCESS_PASSWORD variable. Basic editing works without an AI key. Connect your own supported provider in the editor when you want AI generation.

This is one shared workspace for an individual or mutually trusted group. Anyone with the password can access the same document. It is not a multi-tenant SaaS with isolated user accounts.

Common Use Cases

A private browser-based vector design workspace.
AI-assisted UI concepts and editable design experiments using your own provider credentials.
A shared design canvas for a small, trusted group.
Self-hosted design work that can be explicitly saved and exported.

Dependencies for OpenPencil Hosting

A Railway account with enough resources for the two services and persistent storage.
A supported AI provider key only if you want AI generation; provider charges are separate.
A current browser capable of running the WASM/CanvasKit editor.

Deployment Dependencies

OpenPencil Rust web host, pinned to the v0.8.4 image digest.
Caddy gateway with native password authentication, pinned by image digest.
One Railway volume at /data, holding the bound document and application settings.

Implementation Details

Save explicitly. File → Save writes /data/workspace.op to the volume. Save As downloads an export. Unsaved edits are not autosaved and do not survive restart. The first boot creates an empty document; later boots preserve existing files. Use exports and volume backups for important work.

Private by default. Only the gateway has a public domain. Pages, assets, APIs, and live streams require the generated password. The gateway's /healthz endpoint returns only sanitized health information. Keep the backend private.

Your browser owns its AI keys. Upstream stores browser-entered keys in local storage and sends relevant credentials with AI requests. This template disables shared server persistence of browser credential snapshots. Use a trusted browser profile and clear keys on shared devices.

Exact origins. The gateway rejects browser requests from other origins, and the application retains its native origin checks. If you add a custom domain, update the configured public origin accordingly. Internal AI endpoints require an explicit allowlist; no Ollama server or other inference runtime is bundled.

Clear scope. This template does not include native-only coding-agent CLIs, online collaboration hub infrastructure, separate user accounts, or a cloud file manager. It is an independent deployment wrapper around an upstream prerelease.

Why Deploy OpenPencil on Railway?

Railway provides the public HTTPS endpoint, private service networking, generated configuration, and persistent storage in one project. You can host a password-protected design workspace without assembling those infrastructure pieces manually, while retaining access to the source and control over your deployment.