---
id: simplesat
version: "0.9.2"
license: BSD-3-Clause
license_treatment: permissive
maintenance: aging
---

# simplesat — Prototype for SAT-based dependency handling. This is a work in progress, do not expect any API not to change at this point.

License: permissive · Maintenance: aging · Downloads: 279.2K/mo

## What it is and what it does

Simplesat is a pure-Python implementation of a SAT solver designed to handle package dependency resolution. It reads package metadata and constraints, then uses Boolean satisfiability techniques to determine which versions of which packages can be installed together without conflicts. The solver supports equality and version-range constraints and can detect cyclic dependencies and unsatisfiable scenarios.

The package is explicitly marked as a prototype and work-in-progress, meaning its public API may change without warning. It depends on attrs for data structures, okonomiyaki for version parsing, and six for Python 2/3 compatibility. While it has been maintained across multiple Python versions (3.8–3.12) and receives occasional bug fixes, the long gap since the last release suggests the project is in a stable but not actively developed state.

Use it for:

- Build a custom package manager or dependency resolver that needs to solve complex version constraints without relying on pip or conda.
- Analyze package dependency graphs to detect conflicts, cyclic dependencies, or unsatisfiable requirements before attempting installation.
- Compare dependency resolution strategies by running the same scenario through simplesat and other solvers (e.g., PHP Composer, via the included scripts).
- Prototype or research SAT-based approaches to package management, using simplesat's YAML scenario format and CLI tools.
- Integrate SAT-based constraint solving into a build or deployment system where fine-grained control over version selection is required.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Solves package dependency resolution using Boolean satisfiability (SAT) solving, determining which package versions satisfy a set of constraints.

Yes, if you need a standalone SAT-based dependency resolver and can accept an unstable API and aging codebase. The package has low install friction, no known vulnerabilities, and permissive licensing. However, the explicit prototype status and 498-day gap since the last release suggest it is not actively maintained; use it for research, prototyping, or custom tooling rather than as a drop-in replacement for production package managers. For typical Python packaging, pip or conda are more appropriate.

## Install

pip install simplesat
uv add simplesat
poetry add simplesat

## Installing simplesat

Before you install: Low friction installation with three stable runtime dependencies (attrs, okonomiyaki, six). Maintenance status is aging—last release 498 days ago—but the repository remains active with a recent commit on 2025-04-03 and support for Python 3.8 through 3.12.

License in practice: BSD-3-Clause is permissive; you may use, modify, and distribute this package freely provided you retain the license notice and disclaimer.

Quickstart:

pip install simplesat

from simplesat.resolver import Resolver
from simplesat.pool import Pool

pool = Pool()
resolver = Resolver(pool, policy=None)
# Add packages and constraints, then call resolver.resolve(request)

Requires Python 3.8 or later. The package is explicitly a work-in-progress prototype with an unstable API, so production use should be approached cautiously.

Verify before relying:

- Whether the API stability warnings in the description apply to the current 0.9.2 release or remain a general caveat.
- Real-world performance characteristics when solving large dependency graphs or highly constrained scenarios.
- Whether the aging maintenance status (498 days since last release) signals that the project is stable or abandoned.

## Package facts

- License: BSD-3-Clause (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: aging
- Downloads: 279.2K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

SAT solver dependency resolution, package dependency solver, boolean satisfiability package management, constraint-based package resolver, dependency conflict resolution, package version constraint solver, SAT-based package installation, sat-solver, dependency-resolution, package-management

[View on SkillFed](https://skillfed.io/packages/simplesat) · [View on PyPI](https://pypi.org/project/simplesat/)