Adaptive skill practice — find your level, get sharper.
C# practice
LINQ, async/await, records, and the CLR model
Modern C# and the .NET runtime model, from Microsoft’s official documentation. Value versus reference types (structs, classes, boxing), nullable reference types, properties and init-only setters, records and value equality, pattern matching (switch expressions, property patterns), LINQ (deferred execution and its traps), delegates, events and lambdas, generics with constraints and variance, async/await done right (Task vs ValueTask, the sync-over-async deadlock), exceptions and filters, interfaces (default members, explicit implementation), inheritance and polymorphism (virtual/override/new), and collections and spans. Predict-the-output and spot-the-bug items throughout; every explanation names the principle, the trap, and a rule. Authored to the current stable .NET release.
• Meets you at your level — never too easy, never too hard.
• Adapts every question to how you’re doing.
• Tracks your level over time. Skill practice, not a test.
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