Propulsor is a configuration management system using Rust as a configuration language. It took inspiration from Propellor, which use Haskell instead of Rust.

Each system is defined by a list of properties that Propulsor ensures are satisfied. To use Propulsor, you have to write a Rust program using the Propulsor crate. For each system, you define a function returning a list of properties to ensure.

New properties can be defined either by combining properties together, or by defining each of their characteristics.

Status

Propulsor is still in early development stage.

Features and design requirements

• No domain specific language (DSL), you write the configuration using standard Rust, many errors are detected at build stage.

• Split program in two parts, the configuration, and the properties. The configuration defines the target state of the configured systems. The properties are objects which examine and act on the systems in a idempotent way to ensure the target state of the systems. Many properties are provided with Propulsor itself.

• Combine several properties together, handling dependencies between them.

• Handle dependencies factorization, having several web sites should check that the web server is installed only once.

• Provide a dry run mode, to preview what will be done.

• Low dependencies on remote systems, build the configuration program once locally and run it on several remote hosts.

• Handle containers creation from scratch.

• Provide a recorder to examine the actual actions and results.

• Make writing unit tests easy. You can use an edited recorded session to replay it in tests.

• Provide an encrypted secret storage database.

• Initial support for Debian and FreeBSD systems. Support for other Linux or BSD distributions may be added later.

License

Propulsor is distributed under the MIT license.

Copyright (c) 2025 Nicolas Schodet

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.