What I Build
Production-Ready Tools
Tools Used by Developers Worldwide
EPUB to PDF Converter - Free, Private, In-Browser
Convert EPUB ebooks to PDF instantly in your browser. No file upload, no account needed. Preserves text, images, and formatting from any EPUB file.
Instagram Image Resizer
Resize your images easily for Instagram and other social media platforms by adding a transparent, black, white, or blurred background.
Bookmark Link Checker - Find Broken Links in Your Bookmarks
Upload your browser bookmark HTML file and instantly check every link for broken URLs, redirects, and timeouts. Supports Chrome, Firefox, Safari, and Edge. Export results to CSV, JSON, TXT, or HTML.
Get Early Access to New Tools
Be the first to try new APIs and applications. No noise. Only meaningful releases and practical engineering insights.
Latest Engineering Articles
Discover how to use `pyproject.toml` to create, manage, and distribute Python packages in 2026. This comprehensive guide covers everything from build systems to dependency management and best practices for modern Python development.
Learn how to use the `__main__.py` file to make your Python packages executable. This guide covers the purpose of `__main__.py`, how it differs from `__init__.py`, and best practices for creating command-line interfaces in 2026.
A comprehensive guide to `__init__.py` in Python packages. Learn its core purpose, the hoisting pattern, package security with __all__, namespace packages, and 2026 best practices.
About Serhii Hrekov
I'm a Senior Software Engineer & System Architect specializing in Python, high-performance web backends, and cloud infrastructure (AWS, GCP). Currently working at nCube and Modigie, I created this platform to document real-world engineering solutions, production APIs, and developer tools.