···139139- `[ingest] implement backfill buffer replay`
140140- `[api] add accurate count parameter to stats`
141141- `[db] migrate block storage to msgpack`
142142-143143-<!-- gitnexus:start -->
144144-# GitNexus — Code Intelligence
145145-146146-This project is indexed by GitNexus as **hydrant** (1339 symbols, 3645 relationships, 113 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.
147147-148148-> If any GitNexus tool warns the index is stale, run `npx gitnexus analyze` in terminal first.
149149-150150-## Always Do
151151-152152-- **MUST run impact analysis before editing any symbol.** Before modifying a function, class, or method, run `gitnexus_impact({target: "symbolName", direction: "upstream"})` and report the blast radius (direct callers, affected processes, risk level) to the user.
153153-- **MUST run `gitnexus_detect_changes()` before committing** to verify your changes only affect expected symbols and execution flows.
154154-- **MUST warn the user** if impact analysis returns HIGH or CRITICAL risk before proceeding with edits.
155155-- When exploring unfamiliar code, use `gitnexus_query({query: "concept"})` to find execution flows instead of grepping. It returns process-grouped results ranked by relevance.
156156-- When you need full context on a specific symbol — callers, callees, which execution flows it participates in — use `gitnexus_context({name: "symbolName"})`.
157157-158158-## When Debugging
159159-160160-1. `gitnexus_query({query: "<error or symptom>"})` — find execution flows related to the issue
161161-2. `gitnexus_context({name: "<suspect function>"})` — see all callers, callees, and process participation
162162-3. `READ gitnexus://repo/hydrant/process/{processName}` — trace the full execution flow step by step
163163-4. For regressions: `gitnexus_detect_changes({scope: "compare", base_ref: "main"})` — see what your branch changed
164164-165165-## When Refactoring
166166-167167-- **Renaming**: MUST use `gitnexus_rename({symbol_name: "old", new_name: "new", dry_run: true})` first. Review the preview — graph edits are safe, text_search edits need manual review. Then run with `dry_run: false`.
168168-- **Extracting/Splitting**: MUST run `gitnexus_context({name: "target"})` to see all incoming/outgoing refs, then `gitnexus_impact({target: "target", direction: "upstream"})` to find all external callers before moving code.
169169-- After any refactor: run `gitnexus_detect_changes({scope: "all"})` to verify only expected files changed.
170170-171171-## Never Do
172172-173173-- NEVER edit a function, class, or method without first running `gitnexus_impact` on it.
174174-- NEVER ignore HIGH or CRITICAL risk warnings from impact analysis.
175175-- NEVER rename symbols with find-and-replace — use `gitnexus_rename` which understands the call graph.
176176-- NEVER commit changes without running `gitnexus_detect_changes()` to check affected scope.
177177-178178-## Tools Quick Reference
179179-180180-| Tool | When to use | Command |
181181-|------|-------------|---------|
182182-| `query` | Find code by concept | `gitnexus_query({query: "auth validation"})` |
183183-| `context` | 360-degree view of one symbol | `gitnexus_context({name: "validateUser"})` |
184184-| `impact` | Blast radius before editing | `gitnexus_impact({target: "X", direction: "upstream"})` |
185185-| `detect_changes` | Pre-commit scope check | `gitnexus_detect_changes({scope: "staged"})` |
186186-| `rename` | Safe multi-file rename | `gitnexus_rename({symbol_name: "old", new_name: "new", dry_run: true})` |
187187-| `cypher` | Custom graph queries | `gitnexus_cypher({query: "MATCH ..."})` |
188188-189189-## Impact Risk Levels
190190-191191-| Depth | Meaning | Action |
192192-|-------|---------|--------|
193193-| d=1 | WILL BREAK — direct callers/importers | MUST update these |
194194-| d=2 | LIKELY AFFECTED — indirect deps | Should test |
195195-| d=3 | MAY NEED TESTING — transitive | Test if critical path |
196196-197197-## Resources
198198-199199-| Resource | Use for |
200200-|----------|---------|
201201-| `gitnexus://repo/hydrant/context` | Codebase overview, check index freshness |
202202-| `gitnexus://repo/hydrant/clusters` | All functional areas |
203203-| `gitnexus://repo/hydrant/processes` | All execution flows |
204204-| `gitnexus://repo/hydrant/process/{name}` | Step-by-step execution trace |
205205-206206-## Self-Check Before Finishing
207207-208208-Before completing any code modification task, verify:
209209-1. `gitnexus_impact` was run for all modified symbols
210210-2. No HIGH/CRITICAL risk warnings were ignored
211211-3. `gitnexus_detect_changes()` confirms changes match expected scope
212212-4. All d=1 (WILL BREAK) dependents were updated
213213-214214-## CLI
215215-216216-- Re-index: `npx gitnexus analyze`
217217-- Check freshness: `npx gitnexus status`
218218-- Generate docs: `npx gitnexus wiki`
219219-220220-<!-- gitnexus:end -->