Atheris Fuzz Driver Generator

SkillDev tools

Creates Atheris-based coverage-guided fuzz drivers for Python libraries using FuzzedDataProvider for structured input generation. Includes templates and patterns for different library types (parsers, formatters, serializers, ML frameworks).

Available today. Use it from your connected AI after setup.

Connect ahel once, and every AI you use reads what you have installed.

Then ask your AI: use the Atheris Fuzz Driver Generator skill

What this skill tells your AI

The instructions your AI receives, as published by openlair/openskill in tasks-evolved/setup-fuzzing-py/environment/skills/evo-atheris-fuzz-driver/SKILL.md and read by ahel’s review.

Generates fuzz.py harness files for Python libraries with proper Atheris instrumentation, FuzzedDataProvider usage, and exception handling.

Driver Design Principles

  1. Import target library inside atheris.instrument_imports() context manager
  2. Use FuzzedDataProvider to generate structured typed inputs
  3. Catch only expected exceptions (ValueError, TypeError, domain-specific errors)
  4. Guard with if __name__ == "__main__": block
  5. Use atheris.Setup(sys.argv, TestOneInput) then atheris.Fuzz()

Supported Libraries

  • arrow: Date/time parsing, timestamp boundary testing
  • black: Code formatting with Mode configuration
  • ipython: Input transformation pipeline
  • minisgl: JSON/msgpack parsing (lightweight targets)
  • ujson: Differential fuzzing against stdlib json

Key Functions

  • generate_fuzz_driver(lib_path) - Generate and write fuzz.py for a library
  • get_driver_template(lib_name) - Get driver source code for a library
  • get_exception_handlers_for_lib(lib_name) - Get expected exceptions list
  • create_fuzz_driver_file(lib_path, lib_name) - Write fuzz.py to disk

Usage

import sys
sys.path.insert(0, '/app/environment/skills/evo-atheris-fuzz-driver/scripts')
from fuzz_driver import generate_fuzz_driver, create_fuzz_driver_file

generate_fuzz_driver('/app/arrow')
generate_fuzz_driver('/app/black')

Signals

GitHub stars
89
Forks
4
Last commit
Sep 2026
Advanced
Catalog kind
skill
Gateway key
evo-atheris-fuzz-driver
Source
github.com/openlair/openskill