op-brownfieldlisted

# op-brownfield — inherited code and returning to old projects Greenfield's risk is over-engineering. Brownfield's risk is **breaking working code through ignorant changes.** Different discipline. ## Index | Question / situation | Atomic file | |---|---| | Where do I start in an unfamiliar codebase? Discovery sequence? | `~/.achron-spine/chapters/workflow/08a-discovery-sequence.md` | | First-change patterns — how do I ease in safely? | `~/.achron-spine/chapters/workflow/08b-safety-patterns.md` | | How do I orient Claude to a codebase it's never seen? | `~/.achron-spine/chapters/workflow/08c-teaching-unfamiliar.md` | | Should I rewrite this or extend it? Brownfield anti-patterns? | `~/.achron-spine/chapters/workflow/08d-rewrites.md` | ## How to use 1. If the user is returning to old code or entering an inherited codebase: start with `08a` — discovery sequence. 2. If they're about to change something they don't yet understand: `08b` — safety patterns. 3. If they're prompting Claude to "just look at this codebase and tell me what to do": `08c` — teaching unfamiliar. 4. If they're saying "this should be rewritten": `08d` — the rewrite urge is usually premature. ## Common triggers - "Coming back to this project after months." → 08a - "Inheriting a client's code." → 08a + 08c (security checks) - "I want to clean up this weird code I just found." → 08b (Pattern C — comment, don't rewrite) - "Claude doesn't know this codebase." → 08c (orientation prompt) - "Should I just rewri