For engineering managers
Same team. Same patterns.
When everyone structures code differently, PRs take forever. Give your team shared principles through interactive exercises they actually complete.
SOLID principles, applied
Every principle taught through exercises that make developers apply it to real code. The understanding sticks.
Shared vocabulary
When your team shares the same design principles, code reviews become conversations about tradeoffs instead of arguments about style.
Faster code reviews
Consistent architecture means less back-and-forth. PRs that follow shared patterns merge faster.
SOLID + DRY courses included
Self-paced training your team fits around their sprint work.
Write code from lesson one
Every lesson is an exercise you solve in your browser. Real code, real tests, real feedback.
Structured progression
Each concept builds on the last. You always know what to learn next.
Multiple exercise types
Quizzes, fill-in-the-blank, matching, and code keep every lesson engaging.
Instant feedback
Submit your answer and see test results in milliseconds.
Learn by doing
Solve exercises in your browser from the first lesson.
Join over 5,000 learners
Explore our courses
Pick a course and solve your first exercise.
Dart Course
An interactive Dart course where you code, test, and build apps directly in your browser.
Flutter Course
An interactive Flutter course where you code, test, and build apps directly in your browser.
S.O.L.I.D. Course
Learn the principles of how software should be structured, so you can guide AI to build better systems.
D.R.Y. Course
Learn to identify and eliminate code duplication, making your codebase cleaner and easier to maintain.
System Design Course
Learn how APIs, databases, caching, and load balancing fit together to build scalable systems.
Interactive courses
Every lesson is an exercise with instant feedback.
Align your team this week
Interactive design principles training with team plans.