Imported from adnilis/x-hmsw (AGENTS.md). Install upstream with npx skills add adnilis/x-hmsw. Copyright stays with the author.

GitNexus — Code Intelligence

This project is indexed by GitNexus as x-hmsw (1258 symbols, 3051 relationships, 104 execution flows). Use the GitNexus MCP tools to understand code, assess impact, and navigate safely.

If any GitNexus tool warns the index is stale, run npx gitnexus analyze in terminal first.

Project Overview

x-hmsw is a high-performance vector database implemented in pure Go, designed for large-scale vector similarity search.

Key Features

• Multiple Index Algorithms: HNSW, IVF, Flat, ANN
• Flexible Storage: Badger, BBolt, Pebble, Memory, Mmap
• Text Vectorization: TF-IDF, BM25 (with variants), OpenAI Embeddings
• Vector Compression: PQ, SQ, Binary
• High Performance: SIMD acceleration, object pooling, concurrency control
• Easy to Use: QuickDB provides out-of-the-box simplified interface
• Monitoring: Built-in Prometheus metrics support

Architecture

┌─────────────────────────────────────────────────────────┐
│                    Application Layer                     │
├─────────────────────────────────────────────────────────┤
│                      API Layer                          │
│                   (QuickDB 接口)                         │
├─────────────────────────────────────────────────────────┤
│                   Interface Layer                       │
│              (VectorDB, Index 接口)                      │
├─────────────────────────────────────────────────────────┤
│                 Embedding Layer                         │
│         (TF-IDF, BM25, OpenAI Embeddings)               │
├─────────────────────────────────────────────────────────┤
│                    Index Layer                          │
│         (HNSW, IVF, Flat, ANN 索引实现)                 │
├─────────────────────────────────────────────────────────┤
│                 Compression Layer                       │
│            (PQ, SQ, Binary 压缩)                        │
├─────────────────────────────────────────────────────────┤
│                   Storage Layer                         │
│      (Badger, BBolt, Pebble, Memory, Mmap)             │
├─────────────────────────────────────────────────────────┤
│                    Utils Layer                          │
│         (SIMD, Pool, Math, Concurrency)                 │
├─────────────────────────────────────────────────────────┤
│                  Infrastructure                         │
│              (Metrics, Logging, Serialization)          │
└─────────────────────────────────────────────────────────┘

Directory Structure

• api/: QuickDB simplified API
• embedding/: Text vectorization (TF-IDF, BM25, OpenAI)
• indexes/: Index implementations (HNSW, IVF, Flat, ANN)
• compression/: Vector compression (PQ, SQ, Binary)
• storage/: Storage engines (Badger, BBolt, Pebble, Memory, Mmap)
• interface/: Core interfaces (VectorDB, Index, Storage, Logger)
• types/: Core data types
• utils/: Utility functions (SIMD, Pool, Math, Concurrency)
• metrics/: Prometheus metrics
• serialization/: Data serialization (Protobuf, MessagePack, Binary)
• docs/: Documentation
• examples/: Example code

Always Do

• 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.
• MUST run gitnexus_detect_changes() before committing to verify your changes only affect expected symbols and execution flows.
• MUST warn the user if impact analysis returns HIGH or CRITICAL risk before proceeding with edits.
• When exploring unfamiliar code, use gitnexus_query({query: "concept"}) to find execution flows instead of grepping. It returns process-grouped results ranked by relevance.
• When you need full context on a specific symbol — callers, callees, which execution flows it participates in — use gitnexus_context({name: "symbolName"}).

When Debugging

1. gitnexus_query({query: "<error or symptom>"}) — find execution flows related to the issue
2. gitnexus_context({name: "<suspect function>"}) — see all callers, callees, and process participation
3. READ gitnexus://repo/x-hmsw/process/{processName} — trace the full execution flow step by step
4. For regressions: gitnexus_detect_changes({scope: "compare", base_ref: "main"}) — see what your branch changed

When Refactoring

• 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.
• 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.
• After any refactor: run gitnexus_detect_changes({scope: "all"}) to verify only expected files changed.

Never Do

• NEVER edit a function, class, or method without first running gitnexus_impact on it.
• NEVER ignore HIGH or CRITICAL risk warnings from impact analysis.
• NEVER rename symbols with find-and-replace — use gitnexus_rename which understands the call graph.
• NEVER commit changes without running gitnexus_detect_changes() to check affected scope.

Tools Quick Reference

Impact Risk Levels

Resources

Self-Check Before Finishing

Before completing any code modification task, verify:

1. gitnexus_impact was run for all modified symbols
2. No HIGH/CRITICAL risk warnings were ignored
3. gitnexus_detect_changes() confirms changes match expected scope
4. All d=1 (WILL BREAK) dependents were updated

Keeping the Index Fresh

After committing code changes, the GitNexus index becomes stale. Re-run analyze to update it:

npx gitnexus analyze

If the index previously included embeddings, preserve them by adding --embeddings:

npx gitnexus analyze --embeddings

To check whether embeddings exist, inspect .gitnexus/meta.json — the stats.embeddings field shows the count (0 means no embeddings). Running analyze without --embeddings will delete any previously generated embeddings.

Claude Code users: A PostToolUse hook handles this automatically after git commit and git merge.

CLI

• Re-index: npx gitnexus analyze
• Check freshness: npx gitnexus status
• Generate docs: npx gitnexus wiki