0_SYNC — Multi-Host Synchronization Architecture

What It Does

Real-time file synchronization across 6+ Linux hosts
Git-aware conflict detection and resolution
AI-powered merge via Claude API fallback
Daemon-based with 15-second sync intervals

Tech Stack

Bash (core engine)
rsync over SSH with persistent sockets
Git integration (untracked file sync)
Claude API (conflict resolution)

Synchronized Hosts

15s

Daemon Interval

Sync Engines

Conflict Resolution

Problem Statement

Working across multiple Linux machines (WSL instances, bare-metal servers, cloud VMs) creates a constant challenge: keeping shell environments, scripts, project code, and configurations in sync. Traditional solutions (git alone, cloud sync tools) don't handle the nuance of development workflows — untracked files, environment-specific configs, or real-time shell customizations.

Architecture Overview

┌─────────────────────────────────────────────────────────────────────┐ │ 0_SYNC Architecture │ ├─────────────────────────────────────────────────────────────────────┤ │ │ │ ┌─────────────┐ rsync/SSH ┌─────────────┐ │ │ │ officewsl │◄─────────────►│ server │ │ │ │ (sync hub) │ │ (192.168. │ │ │ └──────┬───────┘ │ 10.15) │ │ │ │ └──────────────┘ │ │ │ rsync/SSH │ │ ├──────────────────────►┌──────────────┐ │ │ │ │ dellserver │ │ │ │ └──────────────┘ │ │ │ │ │ ├──────────────────────►┌──────────────┐ │ │ │ │ app1 │ │ │ │ └──────────────┘ │ │ │ │ │ ├──────────────────────►┌──────────────┐ │ │ │ │ laptopwsl │ │ │ │ └──────────────┘ │ │ │ │ │ └──────────────────────►┌──────────────┐ │ │ │ aws1 / etc. │ │ │ └──────────────┘ │ │ │ │ ┌─────────────────────────────────────────────────────────────┐ │ │ │ Sync Engines │ │ │ ├─────────────────────────────────────────────────────────────┤ │ │ │ sync_environment.sh │ Bash env (.bashrc, aliases) 15s │ │ │ │ sync_wsl_linux.sh │ WSL ↔ Linux (bidirectional) │ │ │ │ sync_project.sh │ Project code (git-aware) │ │ │ │ sync_SCRIPTS.sh │ 0_SCRIPTS directory │ │ │ │ sync_HUBITAT.sh │ Smart home configs │ │ │ │ sync_elfege.com.sh │ Portfolio website │ │ │ │ sync_arduino.sh │ Arduino/IoT projects │ │ │ └─────────────────────────────────────────────────────────────┘ │ │ │ │ ┌─────────────────────────────────────────────────────────────┐ │ │ │ Conflict Resolution │ │ │ ├─────────────────────────────────────────────────────────────┤ │ │ │ 1. MD5 checksum comparison │ │ │ │ 2. 3-way diff3 merge │ │ │ │ 3. Claude API merge (AI fallback) │ │ │ │ 4. Archive + manual review │ │ │ └─────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────┘

Sync Engines

Engine	Purpose	Mode
`sync_environment.sh`	Shell environment files (.bashrc, .bash_aliases, .bash_utils)	Daemon (15s loop) + cron
`sync_wsl_linux.sh`	Full WSL ↔ Linux bidirectional sync	On-demand
`sync_project.sh`	Project code with git-aware conflict detection	On-demand (git-only default)
`sync_SCRIPTS.sh`	0_SCRIPTS directory across all hosts	On-demand
`sync_HUBITAT.sh`	Smart home automation configurations	On-demand
`sync_elfege.com.sh`	Portfolio website deployment	On-demand
`sync_arduino.sh`	Arduino/IoT project files	On-demand

Key Design Decisions

Git-Aware Sync
Only untracked files are synced via rsync. Git-tracked files are left to manual git operations, preventing sync conflicts with version control.
Single-Instance Guard
PID-based locking prevents duplicate daemons. Each engine yields to higher-priority syncs via yield_to_other_sync().
SSH Persistent Sockets
ControlMaster connections with 60s timeout reduce SSH handshake overhead across frequent sync cycles.
AI-Powered Conflict Resolution
When 3-way diff3 merge fails, the Claude API is used as a fallback for intelligent merge decisions — a novel approach to file synchronization.
Project-to-Host Mapping
Associative arrays define which projects sync to which hosts, enabling selective deployment without manual configuration per sync.

Management

Command	Effect
`pause_all.sh`	Pause all sync daemons (writes state file)
`stop_all_syncs.sh`	Kill all running sync processes
`toggle_git_sync_only.sh`	Toggle git-only mode (propagates to all hosts)