Welcome, murmr builders

You talk, murmr types. Now give whatever you’re building a real email backbone — a free builder inbox on builder.mailpipe.dev, on the same AI-native platform our paying teams run.

What you get

Free for builders, real from day one

Builders run on the shared builder.mailpipe.dev domain, so your inbox costs you nothing — and it behaves exactly like the email infrastructure under our production customers.

A real builder inbox

your-handle@builder.mailpipe.dev — send and receive on a real business address. Not a throwaway, no credit card, set up in under a minute.

Programmatic email for what you build

The same pipes our paying teams run on: wire agents into email with MCP, API, and CLI, and route inbound mail with a single JavaScript handler — parse, branch, dispatch however you like.

+14 days of murmr Pro

This account is Level 2 of the Builder Ladder. Creating it is the whole rung — no usage quotas, no extra hoops.

How the rung works

Three steps, no tricks

Your murmr identity and your Mailpipe login stay separate. The only link between the two products is a single anonymous builder ID — no account merge, ever.

Arrive from murmr

Your murmr builder ID — an anonymous UUID, never your email or device — rides along in the link and through signup.

Claim your handle

Pick your-handle@builder.mailpipe.dev and set a password. We provision the inbox and bind your builder ID to it the moment the account is created.

Head back to murmr

Your rung is credited automatically once murmr’s verification hub opens. Signing up today counts from day one — nothing to re-do.

Real today

Your inbox goes live and your builder ID is bound to it at signup. Send, receive, and build on it immediately.

Credited when verification opens

murmr’s verification hub marks the rung complete automatically. Accounts created now count the moment it opens — you won’t redo a thing.

Claim your handle before someone else does

One minute, no card. Then head back to murmr and keep building.