GoAccess is a real-time web log analyzer and interactive viewer
Fast and Lightweight Logs and Metrics processor for Linux, BSD, OSX
AWStats Log Analyzer
ISC dhcpd leases usage analysis
Kafka implemented in Golang with built-in coordination
Open Source SIEM
Log File Monitoring - Check Log Files, Analyze, Alert on any UNIX Log
Squid log data warehouse
Piwik - Remixed!