Open beta launched

The coding gym for Go professionals.

Today's exercise: Basic functionality

Code. Break. Fix. Repeat.

↓ Scroll to learn more ↓

Your training program

SDT is a terminal-based gym where you implement high-load patterns in Go and run them against real failure scenarios.

  • Pick a pattern. Implement the interface in your editor.
  • Run the workout. Your code hits concurrent load, failures, edge cases.
  • See what broke and why. Fix it. Run again.
Enter the Gym →

👇 Watch 90 seconds demo

Not another course. Not another side project.

SDT gives you what courses and pet projects can't — fast reps with instant feedback on production-grade patterns.

Join Beta

Enter the Gym →

🆓 Train for free

2 workouts free forever. No credit card required. No pressure to upgrade.

Beta exclusive

💰 Founders pricing

$199 $99 / year for extra challenges.

🗣️ Gifts for friends

Share special privileges with your friends via special invite codes. Gift them priority support, waitlist skip, or discount.

❤️ You are first

Priority support. New releases first. Feature requests. Direct contact with founders.

Don't worry

🔒 No spam. We send you only 1 email when you get invited.

🔒 No credit card required.

🔒 Free workouts stay free forever.

What does a workout look like?

You get a Go interface and a failing test suite. Implement the pattern, run the tests, see what breaks. Fix and repeat until all cases pass.

Will this help with system design interviews?

Yes. 80% of senior+ interviews include coding a distributed system component. SDT gives you reps on the exact patterns asked in FAANG interviews.

How is this different from LeetCode?

LeetCode = algorithms (single function). SDT = system design (concurrent components). Different muscles, different interviews.

What if I get stuck?

Beta members get priority support via community Slack space.

Can I train for free?

Yes. 2 workouts stay free forever. No credit card required.