What do you want to practice?

Pick a track. Every track starts from the idea, so you understand why something works before you are tested on it.

• Coding

  Data structures and algorithms, learned from the idea first.

  • Sets of problems, from free starter sets to the most-asked 75
  • Drawings you can step through, then a real editor with real tests
  • Python, JavaScript, TypeScript, C#, C++ and C
  Open
• Design

  System design interviews, taught until you could explain them to someone else.

  • The most asked design questions with solutions, diagrams and walkthroughs
  • Deep courses, starting with a free Foundations course
  • Notes and practice for every question
  Open
• Architecture

  How famous systems really work, and why they ended up that way.

  • Case studies of well known systems, each with chapters
  • Explain, explore, expand and exercise in every chapter
  • Built for senior and principal level thinking
  Open
• Technical Executive

  The judgment of a CTO or distinguished engineer: money, risk and the organization behind the systems.

  • Briefs built around real executive decisions, with the numbers
  • What an executive looks at first, and why
  • Written reviews from a CEO, a CTO, a CFO, a skeptical principal and a board or security lead
  Open