Bolt browser builder vs Grain artifact hub

Quick answer

Bolt bundles its own agent with hosting in a web builder whose usage is measured in tokens. Grain starts after generation: your existing coding agent writes the files, and Grain publishes them to a persistent URL with optional Postgres, login and scheduled work. Bolt is the shorter route when you need the builder too. Grain is the cleaner fit when Claude Code, Codex, Cursor or another CLI agent is already how the work gets made.

Fit first

What is different, verifiably

Where Bolt is better

• You want to begin with a plain-language prompt and do not already have a coding agent workflow. Bolt includes the creation surface Grain intentionally lacks.
• You want a database option selected and managed inside the same browser builder rather than having an agent implement against workspace Postgres.
• Your team needs shared access to the building process itself. Bolt Teams addresses membership around the builder; Grain shares the finished artifact.
• You prefer a browser-only workflow and do not want to install a desktop application or work from a local project folder.

Where Grain is better

• You already have a preferred CLI agent and model subscription. Grain does not require a second token allowance or choose the generating agent.
• You do not want the build constrained by Bolt's daily and monthly token allowances or its free-plan 10 MB upload limit because your own agent already creates the files.
• The deliverable may be a report, walkthrough or scheduled job rather than a browser-built app, and it needs a clear free-tier keep-live promise.
• Review needs public, password or invite-only access plus reader comments the agent can use in its next change.
• You want a documented path to pull every artifact as files and an open source core.

Moving between them

1. From Bolt to Grain: obtain the application's source files through Bolt's project workflow. Export is not listed as a Bolt feature, so confirm file access before starting.
2. Put the files in a local folder and run grain init. Grain creates the workspace and writes configuration for Claude Code, Codex and Cursor unless --no-agent-config is used.
3. Ask your agent to inventory database and hosting assumptions. Move schema and data independently into workspace Postgres, and recreate login or scheduled behavior rather than expecting hosted state to accompany source files.
4. Run grain push, grain checkpoint -m "import Bolt app", then grain share --public or grain share --password <pw>. Test the returned URL with the intended access mode.
5. From Grain to Bolt: run grain pull to fetch files, then bring the supported project into Bolt. Grain's Postgres contents, user accounts, schedules, comments, share controls and custom-domain records remain outside the source export.

Choice rule

Choose Bolt

if you need the product to generate the app in a browser and its token-metered builder is the workflow you want.

Choose Grain

if your own CLI coding agent already creates the work and the missing piece is a persistent, controlled home for its output.

Use both

if Bolt provides a fast initial build and you can move the resulting files into your normal agent workflow for Grain-based review and retention.

Frequently asked questions