11 parts · 11 chapters

C# and .NET

A fast, open-source, cross-platform runtime and the backbone of enterprise and banking software worldwide. Measured on this course's laptop with .NET 10.0.12: 100,000 Task.Delay(1000) calls completed together in about 1.07 seconds, and creating 10 million Money values took 29 ms and allocated 240 MB as a class, versus 5 ms and nothing as a struct.

Eleven parts in the shared language-course shape: basics; the type system (value and reference types, nullable reference types, records, generics); the CLR (JIT, tiered compilation, GC, Native AOT); async/await and concurrency; idioms; tooling and testing; ASP.NET Core end to end; ASP.NET Core and EF Core internals; performance; what .NET is paired with in production (Kestrel behind a proxy or IIS, Azure, MassTransit); and the shared capstone, the ledger API in C#.

Start reading · Part 0 Present as slides

basics · the type system · the CLR · async/await and concurrency · idioms · tooling and testing · ASP.NET Core end to end · ASP.NET Core and EF Core internals · performance · in production: what .NET is paired with · capstoneintro → expert · backend engineers, especially in enterprise and fintech

languageC#: records, pattern matching, LINQ, async/await.

runtimeThe CLR: tiered JIT, generational GC, value types.

webASP.NET Core minimal APIs and controllers on Kestrel.

dataEF Core: change tracking, migrations, raw SQL when needed.

productionProxies, Azure, MassTransit, OpenTelemetry.

capstoneThe ledger API with the shared acceptance tests.

Part of the language trackShares its shape and capstone with the Go, Python, Java, Rust, Rails, Kotlin and Elixir courses.

C# and .NET

Basics

The Type System

The CLR

async/await and Concurrency

Idioms

Tooling and Testing

ASP.NET Core End to End

ASP.NET Core and EF Core Internals

Performance

In Production: What .NET Is Paired With

Capstone: The Ledger API in C#