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shinka-setup

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Create ShinkaEvolve task scaffolds from a target directory and task description, producing `evaluate.py` and `initial.<ext>` (multi-language). Use when asked to set up new ShinkaEvolve tasks, evaluation harnesses, or baseline programs for ShinkaEvolve.

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How to use this skill

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Source SKILL.md: https://github.com/SakanaAI/ShinkaEvolve/blob/HEAD/skills/shinka-setup/SKILL.md

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Shinka Task Setup Skill

Create a setup scaffold consisting of an evaluation script and initial solution for an optimization problem given a user's task description. Both ingredients will be used within ShinkaEvolve, a framework combining LLMs with evolutionary algorithms to drive code optimization.

When to Use

Invoke this skill when the user:

  • Wants to optimize code with LLM-driven code evolution (Shinka/ShinkaEvolve)
  • No evaluate.py and initial.<ext> exist in the working directory

User Inputs

  • Task description + success criteria
  • Target language for initial.<ext> (if omitted, default to Python)
  • What parts of the script to optimize
  • Evaluation metric(s) and score direction
  • Number of eval runs / seeds
  • Required assets or data files
  • Dependencies or constraints (runtime, memory)

Workflow

  1. Check if all user inputs are provided and ask the user follow-up questions if not inferrable.
  2. Inspect working directory. Detect chosen language + extension. Avoid overwriting existing evaluate.py or initial.<ext> without consent.
  3. Write initial.<ext> with a clear evolve region (EVOLVE-BLOCK markers or language-equivalent comments) and stable I/O contract.
  4. Write evaluate.py:
    • Python initial.py: call run_shinka_eval with experiment_fn_name, get_experiment_kwargs, aggregate_metrics_fn, num_runs, and optional validate_fn.
    • Non-Python initial.<ext>: run candidate program directly (usually via subprocess) and write metrics.json + correct.json.
  5. Ensure candidate output schema matches evaluator expectations (tuple/dict for Python module eval, or file/CLI contract for non-Python).
  6. Validate draft evaluate.py before handoff:
    • Run a smoke test:
      • python evaluate.py --program_path initial.<ext> --results_dir /tmp/shinka_eval_smoke
    • Confirm evaluator runs without exceptions.
    • Confirm a metrics dict is produced (either from aggregate_fn or metrics.json) with at least:
      • combined_score (numeric),
      • public (dict),
      • private (dict),
      • extra_data (dict),
      • text_feedback (string, can be empty).
    • Confirm correct.json exists with correct (bool) and error (string) fields.
  7. Ask the user if they want to run the evolution themself or whether to use the shinka-run skill:
    • If the user wants to run evolution manually, add run_evo.py plus a shinka.yaml config with matching language + init_program_path.
    • Ask the user if they want to use the shinka-run skill to perform optimization with the agent.

What is ShinkaEvolve?

A framework developed by SakanaAI that combines LLMs with evolutionary algorithms to propose program mutations, that are then evaluated and archived. The goal is to optimize for performance and discover novel scientific insights.

Repo and documentation: https://github.com/SakanaAI/ShinkaEvolve Paper: https://arxiv.org/abs/2212.04180

Evolution Flow

  1. Select parent(s) from archive/population
  2. LLM proposes patch (diff, full rewrite, or crossover)
  3. Evaluate candidate → combined_score
  4. If valid, insert into island archive (higher score = better)
  5. Periodically migrate top solutions between islands
  6. Repeat for N generations

Core Files To Generate

FilePurpose
initial.<ext>Starting solution in the chosen language with an evolve region that LLMs mutate
evaluate.pyScores candidates and emits metrics/correctness outputs that guide selection
run_evo.py(Optional) Launches the evolution loop
shinka.yaml(Optional) Config: generations, islands, LLM models, patch types, etc.

Quick Install (if Shinka is not set up yet)

Install once before creating/running tasks:

# Check if shinka is available in workspace environment
python -c "import shinka"

# If not; install from PyPI
pip install shinka-evolve

# Or with uv
uv pip install shinka-evolve

Language Support (initial.<ext>)

Shinka supports multiple candidate-program languages. Choose one, then keep extension/config/evaluator aligned.

evo_config.languageinitial.<ext>
pythoninitial.py
juliainitial.jl
fortraninitial.f90
cppinitial.cpp
cudainitial.cu
rustinitial.rs
swiftinitial.swift
json / json5initial.json

Rules:

  • evaluate.py stays the evaluator entrypoint.
  • Python candidates: prefer run_shinka_eval + experiment_fn_name.
  • Non-Python candidates: evaluate via subprocess and write metrics.json + correct.json.
  • Always set both evo_config.language and matching evo_config.init_program_path.

Template: initial.<ext> (Python example)

import random

# EVOLVE-BLOCK-START
def advanced_algo():
    # Implement the evolving algorithm here.
    return 0.0, ""
# EVOLVE-BLOCK-END

def solve_problem(params):
    return advanced_algo()

def run_experiment(random_seed: int | None = None, **kwargs):
    """Main entrypoint called by evaluator."""
    if random_seed is not None:
        random.seed(random_seed)

    score, text = solve_problem(kwargs)
    return float(score), text

For non-Python initial.<ext>, keep the same idea: small evolve region + deterministic program interface consumed by evaluate.py.

Template: evaluate.py (Python run_shinka_eval path)

import argparse
import numpy as np

from shinka.core import run_shinka_eval  # required for results storage


def get_kwargs(run_idx: int) -> dict:
    return {"random_seed": int(np.random.randint(0, 1_000_000_000))}


def aggregate_fn(results: list) -> dict:
    scores = [r[0] for r in results]
    texts = [r[1] for r in results if len(r) > 1]
    combined_score = float(np.mean(scores))
    text = texts[0] if texts else ""
    return {
        "combined_score": combined_score,
        "public": {},
        "private": {},
        "extra_data": {},
        "text_feedback": text,
    }


def validate_fn(result):
    # Return (True, None) or (False, "reason")
    return True, None


def main(program_path: str, results_dir: str):
    metrics, correct, err = run_shinka_eval(
        program_path=program_path,
        results_dir=results_dir,
        experiment_fn_name="run_experiment",
        num_runs=3,
        get_experiment_kwargs=get_kwargs,
        aggregate_metrics_fn=aggregate_fn,
        validate_fn=validate_fn,  # Optional
    )
    if not correct:
        raise RuntimeError(err or "Evaluation failed")


if __name__ == "__main__":
    # argparse program path & dir
    parser = argparse.ArgumentParser()
    parser.add_argument("--program_path", required=True)
    parser.add_argument("--results_dir", required=True)
    args = parser.parse_args()
    main(program_path=args.program_path, results_dir=args.results_dir)

Template: evaluate.py (non-Python initial.<ext> path)

import argparse
import json
import os
from pathlib import Path


def main(program_path: str, results_dir: str):
    os.makedirs(results_dir, exist_ok=True)

    # 1) Execute candidate program_path (subprocess / runtime-specific call)
    # 2) Compute task metrics + correctness
    metrics = {
        "combined_score": 0.0,
        "public": {},
        "private": {},
        "extra_data": {},
        "text_feedback": "",
    }
    correct = False
    error = ""

    (Path(results_dir) / "metrics.json").write_text(
        json.dumps(metrics, indent=2), encoding="utf-8"
    )
    (Path(results_dir) / "correct.json").write_text(
        json.dumps({"correct": correct, "error": error}, indent=2), encoding="utf-8"
    )


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--program_path", required=True)
    parser.add_argument("--results_dir", required=True)
    args = parser.parse_args()
    main(program_path=args.program_path, results_dir=args.results_dir)

(Optional) Template: run_evo.py (async)

See skills/shinka-setup/scripts/run_evo.py for an example to edit.

(Optional) Template: shinka.yaml

See skills/shinka-setup/scripts/shinka.yaml for an example to edit.

Notes

  • Keep evolve markers tight; only code inside the region should evolve.
  • Keep evaluator schema stable (combined_score, public, private, extra_data, text_feedback).
  • Python module path: ensure experiment_fn_name matches function name in initial.py.
  • Non-Python path: ensure evaluator/runtime contract matches initial.<ext> CLI/I/O.
  • Higher combined_score values indicate better performance.