# Feishu: an author-reported isolated second app instance

> The author reports using Codex and REA analysis to adapt a separate macOS Feishu copy with its own application identity, data directory and single-instance lock. The account describes local signing and separation checks while retaining the original app unchanged.

- Type: Case study
- Targets: App
- Category: Community REA investigations
- Relationship: Author-reported mixed workflow
- Sources reviewed: 2026-10-17
- Added to the catalog: 2026-10-17
- Original resource: <https://benx.ai/blog/posts/rea-reverse-engineer-feishu-dual-instance/>
- Catalog page: <https://awesomerea.org/resources/feishu-dual-instance-case/>
- Record JSON: <https://awesomerea.org/resources/feishu-dual-instance-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/feishu-dual-instance-case/index.md)

## Requirements & limits

- **Scope:** The report targets Feishu 8.1.17 with REA 6.5.0 on the author’s Mac; reported elapsed times and isolation results.
- **Scope:** The modified copy is locally signed and has automatic updates disabled. The article does not publish a redistributable replacement app or original-source reconstruction.
- **Attribution:** The author attributes some architecture tracing directly to Codex and cites prior feishu-clone work.
- **Limits:** Original hash/signature and process/data separation checks are author-reported.

## Primary sources

1. <https://benx.ai/blog/posts/rea-reverse-engineer-feishu-dual-instance/>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.