The Problem
Windows developers working with large log files face a familiar frustration: Notepad++ freezes on 500MB files, IDEs crash, and PowerShell scripts for log parsing are custom jobs that break on edge cases. Enterprise tools like Splunk and ELK exist, but they're overkill for local debugging workflows.
What FastLog Does
Developer Dmytro Mykytenko has shipped FastLog, a Windows-native CLI tool that reads logs incrementally rather than loading entire files into memory. The architecture is straightforward: C++ for performance, line-by-line processing, no GUI dependencies.
Key capabilities:
- Filter by log level, timestamp, and keywords
- Handle multi-gigabyte files without memory constraints
- Clean command-line output for terminal workflows
Example usage: fastlog analyze server.log --level ERROR
The Business Model
FastLog uses a freemium structure:
- Free version: Single-threaded processing, displays top 50 results, full filtering capabilities
- Pro version ($): Multi-threaded processing, unlimited results, JSON export for automation
The tool is distributed via itch.io as a 105KB download with no installation required.
Market Context
The Windows log analysis space splits between enterprise platforms (compliance-focused, agent-based collection) and developer tools (text editors, scripting). FastLog targets the gap: developers who need better than Notepad++ but don't need Splunk.
Notably absent from the announcement: performance benchmarks, file size limits, or comparison metrics against alternatives like Log Parser Studio or PowerShell's Get-Content -Tail approach.
What to Watch
This is an early release with no independent validation yet. The real test: whether developers working with IIS logs, application traces, or Windows Event exports find it faster than their current workflow. The Pro version's value depends entirely on whether multi-threading delivers enough speed improvement to justify the cost.
Worth noting: The tool addresses a genuine pain point - Windows Event Viewer struggles with granular filtering, and even dedicated analyzers often require CSV exports for detailed queries. Whether a CLI tool gains traction against muscle-memory workflows remains to be seen.
Project page: dmykytenko.itch.io/fastlog