ShinkaEvolve: Towards Open-Ended And Sample-Efficient Program Evolution
Paper · 2025 · Robert Tjarko Lange, Yuki Imajuku and Edoardo Cetin
Summary
LLM-driven evolutionary code search uses language models as mutation operators over a population of programs. It has produced notable discoveries, but leading systems such as AlphaEvolve are closed-source and typically need thousands of candidate evaluations. ShinkaEvolve, from Sakana AI, is an open framework built to cut that cost. It keeps an archive of scored programs split into island subpopulations and adds three mechanisms:
- Parent selection that weighs a program's fitness against how often it has already been expanded.
- A novelty filter that embeds the editable code and, when a proposal is too similar to existing programs, asks an LLM to judge whether it is truly new.
- A bandit that shifts sampling toward the ensemble models that produce fitness gains.
The authors tested it on circle packing, AIME reasoning scaffolds, ALE-Bench competitive programming, and mixture-of-experts load-balancing losses. It found a new best circle packing configuration with roughly 150 evaluations. The open release makes such discovery loops affordable for smaller labs, although LLM API costs remain a barrier.
Key points
- The circle packing result beat AlphaEvolve's reported solution using about 150 program evaluations.
- The novelty filter rejects proposals whose cosine similarity to island programs exceeds 0.95, then calls an LLM-as-a-novelty-judge. In ablations, the filter clearly helped; the judge itself added only a marginal gain.
- Mutations come in three forms: SEARCH/REPLACE diff edits, full rewrites (with EVOLVE-BLOCK markers protecting fixed code), and LLM-based crossover of two programs. The framework supports GPT, Gemini, Claude and DeepSeek models.
- In ablations, weighted parent sampling beat hill climbing and the Best-of-N baseline. The bandit ensemble beat a single GPT-5-nano and a uniform fixed ensemble, though the figure caption describes this gain as slight.
- The code is released under Apache 2.0 at github.com/SakanaAI/ShinkaEvolve, together with a visualization tool. The main stated limitation is that it requires well-defined numerical objectives designed by humans.
Fields, topics and concepts
📚 Shelves 4The field of science this work belongs to (OpenAlex fields).Computer Science · 19,503 worksArtificial Intelligence · 18,805 worksInformation Systems · 1,888 worksComputer Science Applications · 184 works
Cite
Cite as Robert Tjarko Lange, Yuki Imajuku and Edoardo Cetin. 2025. ShinkaEvolve: Towards Open-Ended And Sample-Efficient Program Evolution. arXiv:2509.19349.
@misc{lange2025shinkaevolve,
title = {{ShinkaEvolve: Towards Open-Ended And Sample-Efficient Program Evolution}},
author = {Robert Tjarko Lange, Yuki Imajuku and Edoardo Cetin},
year = {2025},
doi = {10.48550/arxiv.2509.19349},
eprint = {2509.19349},
archivePrefix = {arXiv},
url = {https://doi.org/10.48550/arxiv.2509.19349}
}References
- American invitational mathematics examination, 2023. Problems and solutions, 2023. Published by the Mathematical Association of America / AMC contests. find
- American invitational mathematics examination, 2024. Problems and solutions, 2024. Published by the Mathematical Association of America / AMC contests. find
- American invitational mathematics examination, 2025. Problems and solutions, 2025. Published by the Mathematical Association of America / AMC contests. find
- Anthropic. The claude 3 model family: Opus, sonnet, haiku, 2024. URL https://www-cdn.anthr opic.com/de8ba9b01c9ab7cbabf5c33b80b7bbc618857627/Model_Card_Claude_3.pd f . ↗
- Peter Auer, Nicolo Cesa-Bianchi, and Paul Fischer. Finite-time analysis of the multiarmed bandit problem. Machine learning, 47(2):235–256, 2002. find
- Jeremy Berman. How i got a record 53.6% on arc-agi. https://jeremyberman.substack.com/ p/how-i-got-a-record-536-on-arc-agi , 2025. Accessed: 2025-02-08. ↗
- Yonatan Bisk, Rowan Zellers, Jianfeng Gao, Yejin Choi, et al. Piqa: Reasoning about physical commonsense in natural language. In Proceedings of the AAAI conference on artificial intelligence, volume 34, pages 7432–7439, 2020.
- Peter Clark, Isaac Cowhey, Oren Etzioni, Tushar Khot, Ashish Sabharwal, Carissa Schoenick, and Oyvind Tafjord. Think you have solved question answering? try arc, the ai2 reasoning challenge. arXiv preprint arXiv:1803.05457, 2018.
- Damai Dai, Chengqi Deng, Chenggang Zhao, RX Xu, Huazuo Gao, Deli Chen, Jiashi Li, Wangding Zeng, Xingkai Yu, Yu Wu, et al. Deepseekmoe: Towards ultimate expert specialization in mixture-of-experts language models. arXiv preprint arXiv:2401.06066, 2024. find
- Nan Du, Yanping Huang, Andrew M Dai, Simon Tong, Dmitry Lepikhin, Yuanzhong Xu, Maxim Krikun, Yanqi Zhou, Adams Wei Yu, Orhan Firat, et al. Glam: Efficient scaling of language models with mixture-of-experts. In International conference on machine learning, pages 5547–5569. PMLR, 2022.
- Maxence Faldor, Jenny Zhang, Antoine Cully, and Jeff Clune. Omni-epic: Open-endedness via models of human notions of interestingness with environments programmed in code, 2024. URL https://arxiv.org/abs/2405.15568 . ↗
- William Fedus, Barret Zoph, and Noam Shazeer. Switch transformers: Scaling to trillion parameter models with simple and efficient sparsity. Journal of Machine Learning Research, 23(120):1–39, 2022. find
- Google AI Blog. Our next-generation model: Gemini 1.5. https://blog.google/technology/a i/google-gemini-next-generation-model-february-2024/ , February 2024. Accessed: 2025-07-13. ↗
- Daya Guo, Dejian Yang, Haowei Zhang, Junxiao Song, Ruoyu Zhang, Runxin Xu, Qihao Zhu, Shirong Ma, Peiyi Wang, Xiao Bi, et al. Deepseek-r1: Incentivizing reasoning capability in llms via reinforcement learning. arXiv preprint arXiv:2501.12948, 2025.
- Shengran Hu, Cong Lu, and Jeff Clune. Automated design of agentic systems. arXiv preprint arXiv:2408.08435, 2024.
- Yuki Imajuku, Kohki Horie, Yoichi Iwata, Kensho Aoki, Naohiro Takahashi, and Takuya Akiba. Ale-bench: A benchmark for long-horizon objective-driven algorithm engineering. arXiv preprint arXiv:2506.09050, 2025. — [arXiv:2506.09050](https://arxiv.org/abs/2506.09050) find
- Yuichi Inoue, Kou Misaki, Yuki Imajuku, So Kuroki, Taishi Nakamura, and Takuya Akiba. Wider or deeper? scaling llm inference-time compute with adaptive branching tree search. arXiv preprint arXiv:2503.04412, 2025. — [arXiv:2503.04412](https://arxiv.org/abs/2503.04412) find
- Albert Q Jiang, Alexandre Sablayrolles, Antoine Roux, Arthur Mensch, Blanche Savary, Chris Bamford, Devendra Singh Chaplot, Diego de las Casas, Emma Bou Hanna, Florian Bressand, et al. Mixtral of experts. arXiv preprint arXiv:2401.04088, 2024. find
- Zhengyao Jiang, Dominik Schmidt, Dhruv Srikanth, Dixing Xu, Ian Kaplan, Deniss Jacenko, and Yuxiang Wu. Aide: Ai-driven exploration in the space of code. arXiv preprint arXiv:2502.13138, 2025.
- Robert Lange, Tom Schaul, Yutian Chen, Tom Zahavy, Valentin Dalibard, Chris Lu, Satinder Singh, and Sebastian Flennerhag. Discovering evolution strategies via meta-black-box optimization. In Proceedings of the Companion Conference on Genetic and Evolutionary Computation, pages 29–30, 2023. find
- Robert Tjarko Lange, Yingtao Tian, and Yujin Tang. Large language models as evolution strategies. arXiv preprint arXiv:2402.18381, 2024.
- Robert Tjarko Lange, Aaditya Prasad, Qi Sun, Maxence Faldor, Yujin Tang, and David Ha. The ai cuda engineer: Agentic cuda kernel discovery, optimization and composition. Technical report, Technical report, Sakana AI, 02 2025, 2025. find
- Joel Lehman and Kenneth O Stanley. Abandoning objectives: Evolution through the search for novelty alone. Evolutionary computation, 19(2):189–223, 2011. find
- Joel Lehman, Kenneth O Stanley, et al. Exploiting open-endedness to solve problems through the search for novelty. In ALIFE, pages 329–336, 2008. find
- Joel Lehman, Jeff Clune, Dusan Misevic, Christoph Adami, Lee Altenberg, Julie Beaulieu, Peter J Bentley, Samuel Bernard, Guillaume Beslon, David M Bryson, et al. The surprising creativity of digital evolution: A collection of anecdotes from the evolutionary computation and artificial life research c… find
- Joel Lehman, Jonathan Gordon, Shawn Jain, Kamal Ndousse, Cathy Yeh, and Kenneth O. Stanley. Evolution through large models, 2022. URL https://arxiv.org/abs/2206.08896 . — [arXiv:2206.08896](https://arxiv.org/abs/2206.08896) ↗
- Dmitry Lepikhin, HyoukJoong Lee, Yuanzhong Xu, Dehao Chen, Orhan Firat, Yanping Huang, Maxim Krikun, Noam Shazeer, and Zhifeng Chen. Gshard: Scaling giant models with conditional computation and automatic sharding. arXiv preprint arXiv:2006.16668, 2020. find
- Yujia Li, David Choi, Junyoung Chung, Nate Kushman, Julian Schrittwieser, Rémi Leblond, Tom Eccles, James Keeling, Felix Gimeno, Agustin Dal Lago, et al. Competition-level code generation with alphacode. Science, 378(6624):1092–1097, 2022.
- Fei Liu, Rui Zhang, Zhuoliang Xie, Rui Sun, Kai Li, Xi Lin, Zhenkun Wang, Zhichao Lu, and Qingfu Zhang. Llm4ad: A platform for algorithm design with large language model. arXiv preprint arXiv:2412.17287, 2024a. — [arXiv:2412.17287](https://arxiv.org/abs/2412.17287) find
- Liyuan Liu, Young Jin Kim, Shuohang Wang, Chen Liang, Yelong Shen, Hao Cheng, Xiaodong Liu, Masahiro Tanaka, Xiaoxia Wu, Wenxiang Hu, et al. Grin: Gradient-informed moe. arXiv preprint arXiv:2409.12136, 2024b.
- Ilya Loshchilov and Frank Hutter. arXiv:1711.05101, 2017. find
- Decoupled weight decay regularization. arXiv preprint Chris Lu, Samuel Holt, Claudio Fanconi, Alex James Chan, Jakob Nicolaus Foerster, Mihaela van der Schaar, and Robert Tjarko Lange. Discovering preference optimization algorithms with and for large language models. In The Thirty-eighth Annual Conf…
- Chris Lu, Cong Lu, Robert Tjarko Lange, Jakob Foerster, Jeff Clune, and David Ha. The ai scientist: Towards fully automated open-ended scientific discovery. arXiv preprint arXiv:2408.06292, 2024b.
- Yecheng Jason Ma, William Liang, Guanzhi Wang, De-An Huang, Osbert Bastani, Dinesh Jayaraman, Yuke Zhu, Linxi Fan, and Anima Anandkumar. Eureka: Human-level reward design via coding large language models. arXiv preprint arXiv:2310.12931, 2023.
- Meta-AI. The Llama 4 herd: The beginning of a new era of natively multimodal AI innovation, 2025. URL https://ai.meta.com/blog/llama-4-multimodal-intelligence/ . ↗
- Elliot Meyerson, Mark J Nelson, Herbie Bradley, Adam Gaier, Arash Moradi, Amy K Hoover, and Joel Lehman. Language model crossover: Variation through few-shot prompting. arXiv preprint arXiv:2302.12170, 2023. — [arXiv:2302.12170](https://arxiv.org/abs/2302.12170) find
- Todor Mihaylov, Peter Clark, Tushar Khot, and Ashish Sabharwal. Can a suit of armor conduct electricity? a new dataset for open book question answering. arXiv preprint arXiv:1809.02789, 2018. find
- Niklas Muennighoff, Luca Soldaini, Dirk Groeneveld, Kyle Lo, Jacob Morrison, Sewon Min, Weijia Shi, Pete Walsh, Oyvind Tafjord, Nathan Lambert, et al. Olmoe: Open mixture-of-experts language models. arXiv preprint arXiv:2409.02060, 2024. find
- Alexander Novikov, Ngân Vũ, Marvin Eisenberger, Emilien Dupont, Po-Sen Huang, Adam Zsolt Wagner, Sergey Shirobokov, Borislav Kozlovskii, Francisco JR Ruiz, Abbas Mehrabian, et al. Alphaevolve: A coding agent for scientific and algorithmic discovery. arXiv preprint arXiv:2506.13131, 2025.
- OpenAI. Gpt-4 technical report, 2023.
- Guilherme Penedo, Hynek Kydlíček, Anton Lozhkov, Margaret Mitchell, Colin A Raffel, Leandro Von Werra, Thomas Wolf, et al. The fineweb datasets: Decanting the web for the finest text data at scale. Advances in Neural Information Processing Systems, 37:30811–30849, 2024.
- Zihan Qiu, Zeyu Huang, Bo Zheng, Kaiyue Wen, Zekun Wang, Rui Men, Ivan Titov, Dayiheng Liu, Jingren Zhou, and Junyang Lin. Demons in the detail: On implementing load balancing loss for training specialized mixture-of-expert models. arXiv preprint arXiv:2501.11873, 2025.
- Bernardino Romera-Paredes, Mohammadamin Barekatain, Alexander Novikov, Matej Balog, M Pawan Kumar, Emilien Dupont, Francisco JR Ruiz, Jordan S Ellenberg, Pengming Wang, Omar Fawzi, et al. Mathematical discoveries from program search with large language models. Nature, 625(7995): 468–475, 2024.
- Keisuke Sakaguchi, Ronan Le Bras, Chandra Bhagavatula, and Yejin Choi. Winogrande: An adversarial winograd schema challenge at scale. Communications of the ACM, 64(9):99–106, 2021. find
- Maarten Sap, Hannah Rashkin, Derek Chen, Ronan LeBras, and Yejin Choi. Socialiqa: Commonsense reasoning about social interactions. arXiv preprint arXiv:1904.09728, 2019.
- Asankhaya Sharma. Openevolve: an open-source evolutionary coding agent, 2025. URL https://github.com/codelion/openevolve . ↗
- Noam Shazeer. Glu variants improve transformer. arXiv preprint arXiv:2002.05202, 2020. find
- Noam Shazeer, Azalia Mirhoseini, Krzysztof Maziarz, Andy Davis, Quoc Le, Geoffrey Hinton, and Jeff Dean. Outrageously large neural networks: The sparsely-gated mixture-of-experts layer. arXiv preprint arXiv:1701.06538, 2017. find
- Noah Shinn, Federico Cassano, Ashwin Gopinath, Karthik Narasimhan, and Shunyu Yao. Reflexion: Language agents with verbal reinforcement learning. Advances in Neural Information Processing Systems, 36, 2024.
- Kenneth O Stanley, Joel Lehman, and Lisa Soros. Open-endedness: The last grand challenge you’ve never heard of. While open-endedness could be a force for discovering intelligence, it could also be a component of AI itself, 2017. find
- Jianlin Su, Murtadha Ahmed, Yu Lu, Shengfeng Pan, Wen Bo, and Yunfeng Liu. Roformer: Enhanced transformer with rotary position embedding. Neurocomput., 568(C), February 2024. ISSN 0925-2312. doi: 10.1016/j.neucom.2023.127063. URL https://doi.org/10.1016/j.neucom.2 023.127063 . ↗
- Peter T Szymanski and Michael D Lemmon. Adaptive mixtures of local experts are source coding solutions. In IEEE International Conference on Neural Networks, pages 1391–1396. IEEE, 1993. find
- Alon Talmor, Jonathan Herzig, Nicholas Lourie, and Jonathan Berant. Commonsenseqa: A question answering challenge targeting commonsense knowledge. arXiv preprint arXiv:1811.00937, 2018.
- Reiko Tanese. Distributed genetic algorithms for function optimization. University of Michigan, 1989. find
- Chameleon Team. Chameleon: Mixed-modal early-fusion foundation models. arXiv:2405.09818, 2024. arXiv preprint Gemini Team. Google deepmind. gemini 2.5: Pushing the frontier with advanced reasoning, multimodality, long context, and next generation agentic capabilities. Technical report, Technical Rep…
- Fuzhao Xue, Zian Zheng, Yao Fu, Jinjie Ni, Zangwei Zheng, Wangchunshu Zhou, and Yang You. Open-moe: An early effort on open mixture-of-experts language models. arXiv preprint arXiv:2402.01739, 2024.
- Yutaro Yamada, Robert Tjarko Lange, Cong Lu, Shengran Hu, Chris Lu, Jakob Foerster, Jeff Clune, and David Ha. The ai scientist-v2: Workshop-level automated scientific discovery via agentic tree search. arXiv preprint arXiv:2504.08066, 2025.
- An Yang, Anfeng Li, Baosong Yang, Beichen Zhang, Binyuan Hui, Bo Zheng, Bowen Yu, Chang Gao, Chengen Huang, Chenxu Lv, et al. Qwen3 technical report. arXiv preprint arXiv:2505.09388, 2025.
- Rowan Zellers, Ari Holtzman, Yonatan Bisk, Ali Farhadi, and Yejin Choi. Hellaswag: Can a machine really finish your sentence? arXiv preprint arXiv:1905.07830, 2019. find
- Jenny Zhang, Shengran Hu, Cong Lu, Robert Lange, and Jeff Clune. Darwin godel machine: Open-ended evolution of self-improving agents. arXiv preprint arXiv:2505.22954, 2025.
- Barret Zoph, Irwan Bello, Sameer Kumar, Nan Du, Yanping Huang, Jeff Dean, Noam Shazeer, and William Fedus. St-moe: Designing stable and transferable sparse expert models. arXiv preprint arXiv:2202.08906, 2022. find
Updated
This page in Markdown → https://md.research.elamur.ai/free/en/papers/lange-2025-shinkaevolve-open-ended-sample/