8️⃣ 𝗔𝘂𝘁𝗼𝗙𝗶𝘅𝘁𝘂𝗿𝗲 Produces unrealistic, hard to understand tests with randomly-generated data. 👉 Better choice: Bogus 9️⃣ 𝗡𝗦𝘂𝗯𝘀𝘁𝗶𝘁𝘂𝘁𝗲 Its syntax uses the original interface, leading to confusing, unclear tests. 👉 Better choice: Moq 🔟 𝗡𝗨𝗻𝗶𝘁 Older, verbose framework with outdated practices. 👉 Better choice: xUnit Which harmful packages are you still using in your projects? Drop in the comment below! 👇 —— ♻️ Repost to help your network learn about harmful NuGet packages ➕ Follow me ( @AntonMartyniuk ) to improve your .NET and Architecture Skills

My stack nowadays is: - xunit - nsubstitute - awesomeassertions - autofixture - testcontainers respawn for db-related tests - playwright for e2e if needed - xunit.combinatorial if I need it for more paramtetized cases - stryker for mutation tests when I have the time

Developers who say they don't have time for tests Are lying. Seriosly 👇 Many .NET developers write code for months without a single test. Most say - I don't have time or a budget for tests But in the age of AI... It's never been easier and faster to write any kind of tests. You need to have a good template for your tests. And the AI will follow. ⚠️So, no more excuses for not writing tests. I created a 2026 Testing Cheatsheet that covers everything you need. Save this post. You will thank me later. 📌 Testing Frameworks • xUnit • TUnit • NUnit 📌 Assertions • xUnit Assertions • Shouldly • FluentAssertions (is now paid) 📌 Integration Testing • Testing with .NET Aspire • WebApplicationFactory TestContainers • Respawn 📌 Frontend Testing • Playwright • Selenium 📌 Mocking • NSubstitute • Moq 📌 Fake Data • Bogus • AutoFixture 📌 Snapshot Testing • Verify 📌 Behaviour Testing • ReqNRoll • SpecFlow (not maintained anymore) 📌 Performance Testing • BenchmarkDotNet • k6 • NBomber (paid for commercial usage) • JMeter Here is what I recommend in 2026: ✅ xUnit remains the most popular testing framework ✅ TUnit is a modern alternative worth exploring ✅ Shouldly is my go-to for readable assertions ✅ NSubstitute has the cleanest mocking API ✅ Bogus makes generating fake data easy ✅ Aspire provides the easiest way to write integration tests ✅ TestContainers spins up real databases in your tests ✅ Respawn resets your database between integration tests ✅ Playwright is the best choice for frontend testing today ✅ BenchmarkDotNet is the standard for micro-benchmarking in .NET ✅ k6 is excellent for load testing APIs ✅ NBomber allows you to reuse existing C# code for load tests ❌ Avoid **SpecFlow** → it is no longer maintained ❌ Be aware **FluentAssertions** is now a paid library 👉 You don't need every tool on this list. Here is your plan for adopting tests: 1. Unit Tests 2. Integration tests. 3. Load (performance) tests 4. Frontend (E2E) tests 📌 I have created a free guide for you on integration testing in Aspire: antondevtips.com/blog/dotnet… Which testing tools are you using in 2026? Share in the comments 👇 —— ♻️ Repost to help other .NET developers write better tests ➕ Follow me ( @AntonMartyniuk ) to improve your .NET and Architecture Skills

Até agora vendo sobre testes de integração com AutoFixture, MongoDBFixture & Bogus utilizando padrão AAA. Estava odiando no começo, agora odeio menos 🤓 literalmente sou este esquilo no momento

1. Mapperly! 4. Awesome Assertions is also an alternative. 6. Sometimes you really need the power of not default DI container. 8. Their philosophy is slightly different. Bogus is documented even worse than AutoFixture.

𝗧𝗼𝗽 𝟭𝟬 𝗺𝗼𝘀𝘁 𝗵𝗮𝗿𝗺𝗳𝘂𝗹 𝗡𝘂𝗚𝗲𝘁 𝗽𝗮𝗰𝗸𝗮𝗴𝗲𝘀 𝘆𝗼𝘂'𝗿𝗲 𝘂𝘀𝗶𝗻𝗴 𝘄𝗶𝘁𝗵𝗼𝘂𝘁 𝗿𝗲𝗮𝗹𝗶𝘇𝗶𝗻𝗴 𝗶𝘁! You might think these popular .NET packages make your life easier — but they often introduce hidden issues 👇 1️⃣ 𝗔𝘂𝘁𝗼𝗠𝗮𝗽𝗽𝗲𝗿 Encourages overly-complex mapping logic hidden behind profiles. AutoMapper is slow and makes debugging almost impossible. 👉 Better choice: Manual mapping 2️⃣ 𝗠𝗲𝗱𝗶𝗮𝘁𝗥 Adds unnecessary reflection overhead and complexity. 👉 Better choice: Own manual handlers 3️⃣ 𝗡𝗲𝘄𝘁𝗼𝗻𝘀𝗼𝗳𝘁.𝗝𝘀𝗼𝗻 Heavy and slower compared to newer, built-in options. 👉 Better choice: System.Text.Json 4️⃣ 𝗙𝗹𝘂𝗲𝗻𝘁𝗔𝘀𝘀𝗲𝗿𝘁𝗶𝗼𝗻𝘀 Now has a paid license for commercial use. 👉 Better choice: Shouldly or xUnit assertions 5️⃣ 𝗥𝗲𝘀𝘁𝗦𝗵𝗮𝗿𝗽 Has become outdated and less intuitive compared to modern HTTP clients. 👉 Better choice: Refit 6️⃣ 𝗔𝘂𝘁𝗼𝗙𝗮𝗰 Outdated DI container adding unnecessary complexity. 👉 Better choice: Microsoft DI 7️⃣ NServiceBus Expensive licensing model in production and complex setup. 👉 Better choice: MassTransit, Wolverine 8️⃣ 𝗔𝘂𝘁𝗼𝗙𝗶𝘅𝘁𝘂𝗿𝗲 Produces unrealistic, hard to understand tests with randomly-generated data. 👉 Better choice: Bogus 9️⃣ 𝗡𝗦𝘂𝗯𝘀𝘁𝗶𝘁𝘂𝘁𝗲 Its syntax uses the original interface, leading to confusing, unclear tests. 👉 Better choice: Moq 🔟 𝗡𝗨𝗻𝗶𝘁 Older, verbose framework with outdated practices. 👉 Better choice: xUnit Which harmful packages are you still using in your projects? Drop in the comment below! 👇 ♻️ Repost to help your network learn about harmful NuGet packages ➕ Follow me (@AntonMartyniuk) for more #Dotnet

.𝗡𝗘𝗧 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 𝗥𝗼𝗮𝗱𝗺𝗮𝗽 𝗳𝗼𝗿 𝟮𝟬𝟮𝟱. I have been coding in C# for more than 15 years now, and I am often asked how to learn C#/.NET development, what learning resources to use, etc. Here's a roadmap to master C# / .NET development. 📂 𝗡𝗘𝗧 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 𝗥𝗼𝗮𝗱𝗺𝗮𝗽 ∟📂 C# └📄 Learn basics of C# 6 - 13 └📄 Learn .NET 8 and .NET 9 └📄 Learn dotnet CLI ∟📂 General Development skills └📄 Learn Git └📄 Learn HTTP/HTTPS └📄 Learn data structures and algorithms └📄 Learn SOLID, YAGNI, DRY, KISS principles └📄 Learn Design Patterns ∟📂 ASP. NET Core └📄 MVC └📂 APIs └📄 REST └📄 GraphQL └📄 gRPC └📄 Web APIs └📄 Minimal APIs └📄 Middlewares └📄 Filters & Attributes └📄 Authentication & Authorisation ∟📂 Client-Side .NET └📄 Razor └📄 Blazor └📄 .NET MAUI ∟📂 Databases └📄 Database design & SQL └📄 Stored procedures └📂 DBMS └📂 Relational └📄 SQL Server └📄 Postrges └📄 MySQL/MariaDB └📂 NoSQL └📄 MongoDB └📄 RavenDB └📄 CosmosDB ∟📂 ORM └📂 Entity Framework Core └📄 Learn basics └📄 Code first & migrations └📄 Change tracker API └📄 Lazy/eager loading ∟📂 Caching └📄 Memory Cache └📄 Redis └📄 Application-level ∟📂 Logging └📄 Serilog └📄 NLog ∟📂 Real-time communication └📄 SignalR Core └📄 Web Sockets ∟📂 Background tasks └📄 Native Backround Service └📄 HangFire └📄 Quartz ∟📂 Object Mapping └📄 AutoMapper └📄 Mapster ∟📂 Testing └📂 Unit Testing └📂 Frameworks └📄 xUnit └📄 NUnit └📂 Mocking └📄 NSubstitute └📄 Moq └📂 Assertion └📄 FluentAssertions └📂 Test Data Generators └📄 Bogus └📄 AutoFixture └📂 Integration Testing └📄 WebApplicationFactory └📄 TestServer └📂 Snapshot Testing └📄 Verify └📂 End-to-End Testing └📄 Playwright └📂 Performance Testing └📄 K6 └📄 JMeter ∟📂 Monitoring & Telemetry └📄 OpenTelemetry (Jeager) └📄 Prometheus └📄 Grafana └📄 ELK Stack └📄 Datadog ∟📂 Cloud └📄 Azure └📄 AWS ∟📂 Continous integration & delivery └📄 GitHub actions └📄 GitLab CI └📄 Azure Pipelines └📄 Jenkins ∟📂 .NET Libraries └📄 MediatR └📄 Polly └📄 FluentValidation 👉 Check my complete .NET Developer roadmap with other learning resources in my Ultimate .NET Bundle: patreon.com/techworld_with_m…. (Use 64E76 code for 39% off until the end of the week) #technology #softwarengineering #programming #charp #dotnet

In this post, @KyleMcMaster shows us how to use AutoFixture to generate test data and how it can help you write better tests: bit.ly/4d1Bw1I #TestDrivenDevelopment #TDD

Guard classes using FluentAssertions please. Config via IOptions<T>. Add unit and integration tests. Use Moq for all the DI stuff, FluentAssertions, AutoFixture We're several hundred lines of code in and the tests fail.... Oh, we forgot the 5 lines that actually send the email.

.𝗡𝗘𝗧 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 𝗥𝗼𝗮𝗱𝗺𝗮𝗽 𝗳𝗼𝗿 𝟮𝟬𝟮𝟰. I have been coding in C# for over 15 years and am often asked how to learn C#/.NET development, what learning resources to use, etc. Here's a roadmap to Master C# / .NET development. 📂 𝗡𝗘𝗧 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 𝗥𝗼𝗮𝗱𝗺𝗮𝗽 ∟📂 C# └📄 Learn basics of C# 6 - 13 └📄 Learn .NET 8 and .NET 9 └📄 Learn dotnet CLI ∟📂 General Development skills └📄 Learn Git └📄 Learn HTTP/HTTPS └📄 Learn data structures and algorithms └📄 Learn SOLID, YAGNI, DRY, KISS principles └📄 Learn Design Patterns ∟📂 ASP. NET Core └📄 MVC └📂 APIs └📄 REST └📄 GraphQL └📄 gRPC └📄 Web APIs └📄 Minimal APIs └📄 Middlewares └📄 Filters & Attributes └📄 Authentication & Authorisation ∟📂 Client-Side .NET └📄 Razor └📄 Blazor └📄 .NET MAUI ∟📂 Databases └📄 Database design & SQL └📄 Stored procedures └📂 DBMS └📂 Relational └📄 SQL Server └📄 Postrges └📄 MySQL/MariaDB └📂 NoSQL └📄 MongoDB └📄 RavenDB └📄 CosmosDB ∟📂 ORM └📂 Entity Framework Core └📄 Learn basics └📄 Code first & migrations └📄 Change tracker API └📄 Lazy/eager loading ∟📂 Caching └📄 Memory Cache └📄 Redis └📄 Application-level ∟📂 Logging └📄 Serilog └📄 NLog ∟📂 Real-time communication └📄 SignalR Core └📄 Web Sockets ∟📂 Background tasks └📄 Native Backround Service └📄 HangFire └📄 Quartz ∟📂 Object Mapping └📄 AutoMapper └📄 Mapster ∟📂 Testing └📂 Unit Testing └📂 Frameworks └📄 xUnit └📄 NUnit └📂 Mocking └📄 NSubstitute └📄 Moq └📂 Assertion └📄 FluentAssertions └📂 Test Data Generators └📄 Bogus └📄 AutoFixture └📂 Integration Testing └📄 WebApplicationFactory └📄 TestServer └📂 Snapshot Testing └📄 Verify └📂 End-to-End Testing └📄 Playwright └📂 Performance Testing └📄 K6 └📄 JMeter ∟📂 Monitoring & Telemetry └📄 OpenTelemetry (Jeager) └📄 Prometheus └📄 Grafana └📄 ELK Stack └📄 Datadog ∟📂 Cloud └📄 Azure └📄 AWS ∟📂 Continous integration & delivery └📄 GitHub actions └📄 GitLab CI └📄 Azure Pipelines └📄 Jenkins ∟📂 .NET Libraries └📄 MediatR └📄 Polly └📄 FluentValidation Is anything missing? #programming #charp #dotnet

Love autofixture

xUnit, Moq, FluentAssertions, Autofixture, Autofixture Automoq

TDD in golang is TeeDDiious Not sure if there a mocking and autofixture libraries but everything is so long. Might be worth grouping with other devs to do something similar to Moq and AutoFixture that C# has to make life eaiser. @anthdm wdyt any tips.

I just edit the test and switch Fact to Theory and add a [RepeatAttribute(1000)] - usually 1,000 iterations is enough to find the bug. Hack: Use CsCheck instead of frameworks like AutoFixture, and shrink your bug repro down to a well-defined bad input that breaks the test.

In this post, @KyleMcMaster shows us how to use AutoFixture to generate test data and how it can help you write better tests: bit.ly/3t4hClT #TestDrivenDevelopment #TDD

A lot of people do use Autofac, Moq, Autofixture etc... but this doesn't really meet the standards of being able create humanizer quality code without a lot of setup and teardown. Instead just have the ai do that for you, authorize the specific area the user has authroization for, and then only that data and those methods can be debugged. You keep iterating iteratively until you uncover the necessary breadth of the bug or feature, then you update the ticket to explain the correct scope, environment, set of classes and methods, get approval from like a lead or senior dev, then tackle the problem. Then once the work is complete then your senior dev can verify the code solution matches the expectation. Establed your earned value, actual value relationship and estimated values roughly match and complete the ticket.

I would rather go with something like AutoFixture. Writing all these builders just to get a nicer syntax to setup test data seems like too much work for me.

Blogged: Using AutoFixture with EF Core without circular references This will be part of a series of a few posts that detail some helpful practices when writing tests that involve EF Core. #dotnet daninacan.com/using-autofixt…

Moq AutoFixture Have used Telerik's JustMock as well ... NSubstitute looks almost identical to Moq, with a couple of less lines. I just wonder how else the two compare

In this post, @KyleMcMaster shows us how to use AutoFixture to generate test data and how it can help you write better tests: bit.ly/3t4hClT #TestDrivenDevelopment #TDD