v1.9.1 - The Reliability Audit & C# Integration

This release marks a massive milestone in Arbor’s internal stability and test coverage. Following a comprehensive codebase audit, we've radically hardened the underlying graph engine, implemented heavy test automation, and officially introduced native parsing for C#.

Architectural & Engine Fixes

• Stable Graph Migration: We uncovered and resolved a severe hidden bug where deleting source files would trigger silent index corruption within the relational graph. Arbor's core representation engine has now successfully migrated to StableDiGraph, ensuring 100% deterministic, immutable indexing across the entire node universe even during heavy live-edits.

• Search Engine Strictness: Enforced strict safeguards in the SearchIndex to prevent empty query strings ("") from causing false-positive graph flooding, heavily optimizing query memory mapping.

New Language Support

• Full C# Tree-Sitter Integration: Arbor now natively indexes .cs structures including Classes, Structs, Interfaces, Properties, Constructors, and Enums!

• Context-Aware Visibility: C# processing is incredibly intelligent; we implemented upward tree-traversal logic (node.parent()) allowing Arbor to contextually infer default C# accessibility patterns perfectly matching the official spec (public for interfaces, private for classes/structs, internal for namespace compilation units).

• Kotlin Fallback Enhancement: Explicitly brought data class definitions into the fallback parsing suite line-check logic.

• Expanded Extension Synchronization: Server configs now dynamically enforce and track extended JS module variants (.mts, .cts, .mjs, .cjs) and Python stubs (.pyi), perfectly linking the server runtime definitions with core engine capabilities.

Unprecedented Test Coverage

Automated security and algorithmic logic is paramount. We implemented 35+ new high-value unit and integration tests validating boundaries, fallback mechanisms, heuristics algorithms, and edge-handling—pushing the framework to 100% operational test coverage across the full Rust CI workspace!

Full Changelog: v1.9.0...v1.9.1

🤖 Arbor MCP Quick Install

Use Arbor as a local MCP server in your AI client:

Claude Code (project-scoped)

claude mcp add --transport stdio --scope project arbor -- arbor bridge
claude mcp list

In Claude Code, run:

/mcp

Cursor MCP config (.cursor/mcp.json)

{
  "mcpServers": {
    "arbor": {
      "command": "arbor",
      "args": ["bridge"]
    }
  }
}

VS Code MCP config (.vscode/mcp.json)

{
  "servers": {
    "arbor": {
      "type": "stdio",
      "command": "arbor",
      "args": ["bridge"]
    }
  },
  "inputs": []
}

MCP Directories

• Glama: https://glama.ai/mcp/servers/@Anandb71/arbor
• Skills Playground: https://skillsplayground.com/mcps/nandb71-arbor/

Arbor v1.9.1

Installation

# Cargo
cargo install arbor-graph-cli --version 1.9.1

# Homebrew (macOS/Linux)
brew install Anandb71/tap/arbor

# Scoop (Windows)
scoop bucket add arbor https://github.com/Anandb71/arbor
scoop install arbor

# npm
npx @anandb71/arbor-cli

# Docker
docker pull ghcr.io/anandb71/arbor:v1.9.1

Assets

Platform	Architecture	File
Linux	x86_64	arbor-linux-x86_64.tar.gz
Linux	aarch64	arbor-linux-aarch64.tar.gz
macOS	x86_64	arbor-macos-x86_64.tar.gz
macOS	Apple Silicon	arbor-macos-aarch64.tar.gz
Windows	x86_64	arbor-windows-x86_64.zip

What's Changed

• chore: Extensive architectural audit, graph engine fixes, and 35+ new… by @Anandb71 in #120

Full Changelog: 1.9.0.0...v1.9.1