# The Genome > The Genome is Empryo's live, ranked map of your repository. It goes into every prompt so the agent knows where code lives before it starts searching. The **Genome** is a map of your codebase that Empryo builds when you open a project. It lists your files, the symbols they export and how files depend on each other, ranked by importance. A compact version of the map goes at the top of every prompt. Because the agent can see the map, it rarely needs to spend a turn asking "where does auth live?" It starts from the right files. ## What the agent sees A slice of the map looks like this: ``` src/services/auth/session.ts (→12) +SessionManager Tracks active sessions, refresh tokens, expiry +SessionStore ``` - `+` marks an exported symbol. - `(→12)` means 12 other files depend on this one. - `[NEW]` marks a file changed in the last 48 hours. - The text after a symbol name is a one-line summary, when summaries are on. ## How files are ranked - **Dependencies.** Files that many other files import rank higher. - **Your current work.** Files you just edited or mentioned get a boost for that turn. - **Git history.** Files that usually change together are pulled in together. - **Live updates.** When a file changes, the map is updated right away. The scanner understands dozens of languages and file formats, including TypeScript, JavaScript, Python, Rust, Go, Java, C, C++, C#, Ruby, PHP, Swift and Kotlin. ## Settings The Genome works without any setup. Open `/genome` to see its status, rebuild or clear the index, or turn it off. To change it in config: ```json { "genome": true, "semanticSummaries": "synthetic" } ``` | Key | Values | |-----|--------| | `genome` | `true` (default), or `false` to turn the map off | | `semanticSummaries` | `"synthetic"` (free, derived from code and names), `"ast"` (docstrings only), `"llm"` (short model-written descriptions, costs tokens), `"full"`, or `"off"` | ## What gets scanned The scan sees what git sees: tracked and untracked files, minus anything your `.gitignore` excludes. Build output (`node_modules`, `dist`, `build`, `target`, `coverage` and similar) and dot-directories such as `.github` are skipped even if they are tracked. Outside a git repository, the same rules apply to a plain folder scan. To bring a dot-directory back, negate it in `.empryoignore`, for example `!Configs/.local/`. Build output and internal folders such as `.git` stay out either way. ### Keep files out of the map Some files should stay in git but not in the map: test fixtures, benchmark inputs, a folder of SVGs. List them in a **`.empryoignore`** file at the project root. It uses the same syntax as `.gitignore`, including `!` negations and `**`: ```gitignore # Keep these in git, but out of the Genome testenvs/ bench/ assets/ public/ ``` Some files stay out in every project without any `.empryoignore`: package lockfiles (`bun.lock`, `package-lock.json`, `Cargo.lock` and the like), minified and bundled JavaScript, test snapshots, generated protobuf and Dart files, Xcode asset catalogs, and vendored folders such as `vendor/`, `venv/`, `Pods/` and `DerivedData/`. A `!` line in `.empryoignore` brings any of them back. What happens: - Matching files drop out of the map and out of code-wide file listings. - The agent can still `read` or `grep` them by explicit path. They are hidden from discovery, not blocked. - Saving `.empryoignore` or `.gitignore` triggers a quick rescan. Unchanged files are skipped, so it takes seconds. - If a change would remove more than 80% of the index at once, Empryo treats it as a mistake and refuses. Use **clear** in `/genome` to force a rebuild. ### Large repositories The map holds up to 10,000 files. In bigger repositories, the most recently changed files win, and `/genome` tells you the cap was reached. Excluding noise with `.empryoignore` makes sure the cap cuts fixtures rather than source code. ## Skip the scan For a quick one-off question in headless mode, you can skip the scan: ```bash empryo --headless --no-genome "what's the version?" ``` Setting the environment variable `EMPRYO_NO_GENOME=1` does the same.