Introducing ONCE

Introducing ONCE

Once upon a time you owned what you paid for, you controlled what you depended on, and your privacy and security were your own business. We think it’s that time again.

Created Aug 30, 2025
Updated May 31, 2026

What it is

ONCE is a line of self-hosted software products from 37signals that operates on a one-time purchase model. It is designed for businesses and IT departments that want to own their software outright, control their own data, and avoid recurring subscription fees. The products are positioned as alternatives to common Software-as-a-Service (SaaS) applications.

Main Features

Core Model

  • One-Time Purchase: Customers pay a single, fixed price to own the software license forever.
  • Self-Hosted Deployment: Users host and run the software on their own servers or infrastructure.
  • Source Code Access: Buyers are granted access to view the application's source code.
  • Simplified Design: Software is designed to be straightforward and avoid enterprise-level complexity and bloat.

Available Products

  • Campfire: A group chat system designed as a simpler alternative to Slack or Microsoft Teams.
  • Writebook: A tool for publishing books online, marketed as the easiest way to do so.

How it works

Deployment and Ownership

After a one-time purchase, the customer receives the software and is responsible for installing and hosting it on their own servers. This gives the organization full control over the software's operation, data, security, and privacy.

Ongoing Use

Once installed, the software continues to function indefinitely without requiring ongoing payments to the vendor. There is no subscription to maintain, and the software does not deactivate if payments stop.

Key Points

  • The product line is a direct critique of the standard SaaS subscription model, which the creators refer to as a perpetual landlord–tenant agreement.
  • It is built on the premise that modern self-hosting technology has become simpler, making this model more feasible for organizations.
  • The initiative is led by 37signals, a company that was an early pioneer of the SaaS model and is now advocating for a shift away from it.
  • Customers are subject to a software license agreement that governs the use of the products.

Additional Details

  • The products are designed, built, and backed by 37signals.
  • The initial two products are Campfire (group chat) and Writebook (online book publishing).
  • More products under the ONCE brand are anticipated in the future.
  • All rights are reserved by 37signals LLC.
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