What I Build
APIs & Backend Services
Scalable APIs designed for automation, integration, and real-world production use.
Web Tools & Utilities
Focused applications that solve specific technical and operational problems.
Engineering Guides
Step-by-step articles that break down complex backend and cloud topics into practical solutions.
Featured Tools and Applications
27 tools built and maintainedJWT Secret Key Generator
Generate cryptographically secure secret keys for JWT authentication with one-click formatting for .env files.
Strong Password Generator
A secure microservice for generating highly random and strong passwords with full control over character sets and length.
Barcode Generator
Generate Barcodes images instantly using our interactive Bar code generator powered by a dedicated API backend. Enter text or a URL to see your Bar code created in real time! Download the generated Bar code as a PNG image.
Latest Engineering Articles
242 in-depth backend & Python guidesThis error occurs when your local Git history has diverged from the remote. Here are 5 ways to fix it, ranked from "Standard Practice" to "Nuclear Option."
While Pydantic is the industry standard for external data (APIs, JSON parsing), Python's built-in dataclasses are often the better choice for internal data. Here are 4 reasons why.
Learn how to create stunning, scannable QR codes using AI image generation models like Stable Diffusion combined with ControlNet for structure preservation.
Build Smarter Systems
Get notified when I release new APIs, tools, and practical engineering breakdowns. No noise - only useful updates.
About
Hi, I'm Serhii Hrekov - a software engineer focused on building practical APIs, web tools, and backend systems that solve real-world problems. On this site, I share engineering insights and ship tools used by developers and businesses worldwide.