What is source-available software?
Source-available software publishes its source code for anyone to read, but under a licence that restricts some uses, such as offering it as a competing service. It is not open source in the sense of the Open Source Initiative definition.
Written by Ugo Balducci. Last updated
Source-available versus open source
Open-source licences, as defined by the Open Source Initiative in its Open Source Definition, let anyone use, study, change and redistribute the software for any purpose, including commercial ones. Source-available licences keep the first part, publishing the code, and add conditions. Common conditions forbid offering the software as a hosted service that competes with the vendor, limit use to internal business purposes, or reserve some features for a paid edition.
Well-known examples include the Business Source License, the Elastic License, the Server Side Public License and the Functional Source License. The Business Source License and the Functional Source License turn into an open-source licence after a set period. n8n, the workflow automation tool, is distributed under its own Sustainable Use License, which allows use for internal business purposes.
Vendors choose these licences to fund development while keeping the code public. For the organisation running the software, the practical difference is that the licence has to be read, not assumed.
What it means when you self-host
For most organisations running software for their own staff, a source-available licence works much like an open-source one. You can inspect the code, audit its security, run it on your own machines and keep your data in formats you control. The restrictions mostly target companies that would resell the software as a service.
Three questions are worth answering before you commit. Does the licence cover the way you plan to use it, including users outside your organisation? Which features sit in a paid edition, and do you need them? And what happens to your rights if the vendor changes the licence for future versions? As a rule, a version already released stays under the licence it was published with, but read the terms to be sure. A change can also split a project: when HashiCorp moved Vault to the Business Source License in 2023, the last open-source code became OpenBao, a fork now run under the Linux Foundation’s OpenSSF and licensed under MPL-2.0.
How Pilae handles it
The Pilae catalogue is made of apps that are open source or source-available, so your data and your configuration always sit in software whose code anyone can read. Before we operate an app for you, we check that its licence permits the way you will use it and tell you where a commercial edition is needed.
Because the code is public, a Pilae exit plan is concrete: your data, configuration and runbooks, handed over in open formats, run on the same software without us. Browse the app catalogue, or read how teams leave SaaS for software they can run themselves.