History

The story of Gradient-Free-Optimizers and its evolution from 2019 to present.


Origins (2019)

Gradient-Free-Optimizers was created in 2019 by Simon Blanke as the optimization backend for Hyperactive. The goal was to provide a unified interface to multiple gradient-free optimization algorithms, making it easy to experiment with different approaches without changing code.

Initial algorithms:

  • Hill Climbing

  • Random Search

  • Grid Search

  • Simulated Annealing

  • Particle Swarm Optimization


Growth (2020-2021)

The library expanded to include more sophisticated algorithms:

Sequential Model-Based Optimization:

  • Bayesian Optimization with Gaussian Processes

  • Tree-structured Parzen Estimator (TPE)

  • Random Forest Optimizer

Population Methods:

  • Genetic Algorithm

  • Evolution Strategy

  • Differential Evolution

Global Methods:

  • DIRECT algorithm

  • Lipschitz Optimization

  • Pattern Search


Maturation (2022-2023)

Focus shifted to stability, testing, and user experience:

  • Comprehensive test suite across Python versions

  • Improved documentation

  • Performance optimizations

  • Better error handling

  • NumPy 2.0 compatibility

  • Constraint support enhancements


Recent Developments (2024-2025)

Continued refinement and modernization:

  • Python 3.10+ support

  • Enhanced type annotations

  • Improved memory efficiency

  • Better API consistency

  • Expanded documentation with examples

  • Community contributions


Design Philosophy Evolution

Core principles maintained:

  1. Simplicity: Dictionary-based search spaces, no complex syntax

  2. Consistency: All algorithms share the same interface

  3. Transparency: No hidden state or magic

  4. Minimal dependencies: Core library only needs NumPy and pandas

Improvements over time:

  • Better separation of concerns

  • More intuitive parameter names

  • Clearer error messages

  • Better documentation


Impact

Usage:

  • Used as backend for Hyperactive

  • Applied in research and industry

  • Taught in optimization courses

  • Featured in academic papers

Community:

  • Active GitHub repository

  • Regular issue discussion and resolution

  • Contributions from researchers and practitioners

  • Integration with other tools


Looking Forward

Future directions:

  • Additional optimization algorithms

  • Performance improvements

  • Enhanced constraint handling

  • Better parallel optimization support (via Hyperactive)

  • Expanded documentation and examples


Timeline

Year

Milestone

2019

Initial release with 5 algorithms

2020

Added SMBO algorithms (Bayesian, TPE)

2021

Reached 20+ algorithms

2022

Comprehensive testing infrastructure

2023

NumPy 2.0 compatibility

2024

Python 3.10+ focus, improved docs

2025

Continued refinement and community growth


Legacy Documentation

Documentation for previous versions of Gradient-Free-Optimizers is still available at the legacy documentation site:

Legacy Documentation (v1.x)

This may be useful if you:

  • Are maintaining projects that use older versions of GFO

  • Need to reference the previous API design

  • Want to compare the old and new documentation


Releases

For detailed release notes and version history, see:


Thank You

Thank you to everyone who has used, tested, reported issues, contributed code, or spread the word about Gradient-Free-Optimizers over the years!