Guides and build notes

Startups

Bootstrapped to a Billion: What Oxylabs Teaches Founders

In July 2026 Oxylabs sold a slice of the company at a 3.1 billion euro valuation. The headline is not the number. It is the path: eleven years without a single outside investor. Here is what that story tells every founder about bootstrapping, control, and timing.

Building with AI

Claude Code vs Cursor (2026): A Non-Engineer's Honest Comparison

I am not an engineer. I am a founder who ships products using AI coding tools every day. I have built features, full sites, and internal tools with both Claude Code and Cursor. Here is what actually matters when choosing between them.

AI Agents

Personal AI Assistant: The Complete Guide for 2026

A personal AI assistant is no longer a sci-fi concept or a glorified timer. In 2026, you can build one that knows your business, drafts your emails, manages your calendar, and takes real action across your tools. Here is the complete guide.

Founder notes

How We Got Into 500 Global (A Founder's Honest Take)

500 Global is one of the most active early-stage investors in the world, and its accelerators are hard to get into. Callsy made it into the Eurasia batch. Here is what the program actually is, what they look for, and the honest version of how we got in.

Building with AI

How to Use Claude AI: A Beginner's Guide (2026)

I run a company on Claude. I write, plan, research, and even build software with it every day, and I am not an engineer. If you are opening Claude for the first time and wondering what to actually do with it, this is the guide I wish I had. No jargon, just what works.

Artificial intelligence

ChatGPT in Lithuanian: How Good Is It Really?

Everyone writes that ChatGPT handles Lithuanian "perfectly". The research says otherwise. Here is how good it actually is, how to use it free without signing up, and why some "ChatGPT in Lithuanian" sites are not ChatGPT at all.

Artificial intelligence

The Best AI Apps in 2026: Which One for Which Job

The best AI app isn't one list. It's an answer to "what are you actually trying to do?" Here's which app for which job, and where each one falls short.

AI agents

What Is OpenClaw? And What Really Killed the Hype

OpenClaw became the fastest-growing repository in GitHub history, then the hype collapsed. Most explanations blame security. They're wrong. Here's what OpenClaw actually is, what really killed the excitement, and whether you should run it.

Artificial intelligence

Artificial Intelligence: A Practical Guide for 2026

What artificial intelligence is, how it actually works, and how to start using it, both day to day and in business. No jargon, from someone who builds with AI every day.

Artificial intelligence

Free AI: The 7 Best Tools in 2026 (and Where the Free Tier Ends)

The best free AI tools in 2026. No marketing spin: what each one actually does, where the free tier really ends, the privacy reality, and where to start today.

Building companies

How to Build a Business Without Much Capital: 8 Lessons From 0 to €100K

I gave this talk on stage at LOGIN 2025: what 20 years and five companies taught me about building from zero. The lessons, the real examples, and the tools, with no filler.