# MirrorCode: AI can rebuild entire programs from behavior alone

> Tests reimplementation of 25 command-line programs using execute-only reference access, documentation and visible examples. Separate scoring environments compare exact outputs on visible and held-out end-to-end tests.

- Authors: Tom Adamczewski; David Owen; David Rein; Florian Brand; Giles Edkins; Allen Hart; Daniel O'Connell
- Venue: arXiv
- Status: Preprint
- Publication / posting date: June 29, 2026
- Date source: First arXiv submission; the reviewed version is identified separately.
- First arXiv submission: June 29, 2026
- arXiv: 2606.30182
- Reviewed arXiv version: v2
- DOI: 10.48550/arxiv.2606.30182
- Sources reviewed: 2026-10-20
- Added to the catalog: 2026-10-20
- Original paper: <https://arxiv.org/abs/2606.30182>
- PDF: <https://arxiv.org/pdf/2606.30182v2>
- Code: <https://github.com/epoch-research/MirrorCode>
- BibTeX: <https://awesomerea.org/papers/citations/paper-mirrorcode.bib>
- Catalog page: <https://awesomerea.org/papers/paper-mirrorcode/>
- Record JSON: <https://awesomerea.org/papers/paper-mirrorcode/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/papers/paper-mirrorcode/index.md)

## Scope and limitations

Targets are scoped, deterministic, stateless programs with text output. Test agreement is not universal equivalence or code-quality assessment. A memorization screen flags possible exposure for 17 targets. Large inference budgets and scaffold choices limit comparisons with cheaper benchmarks; three targets remain private.

## Why it fits this collection

Directly evaluates sustained reconstruction from observable software behavior.

## Publication and review notes

June 29 first submission, July 17 v2: a six-month-window candidate. Distinct from ProgramBench, explicitly compared in the paper. The pinned repository has an MIT root license and public harness/task definitions, excluding private tasks; target-program licensing is separate.

## Primary sources

1. <https://arxiv.org/abs/2606.30182>
2. <https://arxiv.org/html/2606.30182v2>
3. <https://api.datacite.org/dois/10.48550/arxiv.2606.30182>
4. <https://github.com/epoch-research/MirrorCode/blob/5c9d7b00b0c6d7609003e33896cd41d28f092fcb/README.md>
5. <https://github.com/epoch-research/MirrorCode/blob/5c9d7b00b0c6d7609003e33896cd41d28f092fcb/LICENSE>

## About this entry

Reviewed against the paper and its primary sources. Cite the original authors using the linked paper or BibTeX.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.