dotnet▌

You are an expert .NET/C# backend developer with 8+ years of experience building enterprise-grade APIs and services.

Reverse engineers .NET malware using dnSpy decompiler and debugger to analyze C#/VB.NET source code, identify obfuscation techniques, extract configurations, and understand malicious functionality including stealers, RATs, and loaders. Activates for requests involving .NET malware analysis, C# malware decompilation, managed code reverse engineering, or .NET obfuscation analysis.

Production-grade C#/.NET patterns for APIs, MCP servers, and enterprise backends with modern async, DI, and data access practices. \n \n Covers clean architecture project structure, dependency injection lifetimes, and configuration with IOptions pattern \n Async/await best practices including parallel execution, ConfigureAwait usage, and ValueTask optimization for hot paths \n Entity Framework Core and Dapper repository patterns with query optimization, multi-mapping, and performance considerati

Extract embedded configuration from Agent Tesla RAT samples including SMTP/FTP/Telegram exfiltration credentials, keylogger settings, and C2 endpoints using .NET decompilation and memory analysis.

Analyzes the variety and depth of assertions across .NET test suites. Use when the user asks to evaluate assertion quality, find shallow testing, identify assertion-free tests (no assertions or only trivial ones like Assert.IsNotNull), flag self-referential or tautological assertions (output equals input on identity/round-trip operations), measure assertion coverage diversity, or audit whether tests verify different facets of correctness. Produces metrics and actionable recommendations. Works with MSTest, xUnit, NUnit, TUnit. DO NOT USE FOR: writing new tests (use writing-mstest-tests), other anti-patterns like flakiness or duplication (use test-anti-patterns), or fixing assertions.

Migrate MSTest v1 or v2 test project to MSTest v3. Use when user says "upgrade MSTest", "upgrade to MSTest v3", "migrate to MSTest v3", "update test framework", "modernize tests", "MSTest v3 migration", "MSTest compatibility", "MSTest v2 to v3", or build errors after updating MSTest packages from 1.x/2.x to 3.x. USE FOR: upgrading from MSTest v1 assembly references (Microsoft.VisualStudio.QualityTools.UnitTestFramework) or MSTest v2 NuGet (MSTest.TestFramework 1.x-2.x) to MSTest v3, fixing assertion overload errors (AreEqual/AreNotEqual), updating DataRow constructors, replacing .testsettings with .runsettings, timeout behavior changes, target framework compatibility (.NET 5 dropped -- use .NET 6+; .NET Fx older than 4.6.2 dropped), adopting MSTest.Sdk. First step toward MSTest v4 -- after this, use migrate-mstest-v3-to-v4. DO NOT USE FOR: migrating to MSTest v4 (use migrate-mstest-v3-to-v4), migrating between frameworks (MSTest to xUnit/NUnit), or general .NET upgrades unrelated to MSTest.

Migrates .NET test projects from VSTest to Microsoft.Testing.Platform (MTP). Use when user asks to "migrate to MTP", "switch from VSTest", "enable Microsoft.Testing.Platform", "use MTP runner", or mentions EnableMSTestRunner, EnableNUnitRunner, or UseMicrosoftTestingPlatformRunner. USE FOR: MTP behavioral differences vs VSTest (exit code 8, zero tests discovered), --ignore-exit-code, TESTINGPLATFORM_EXITCODE_IGNORE. Supports MSTest, NUnit, xUnit.net v2 (via YTest.MTP.XUnit2), and xUnit.net v3 (native MTP). Covers runner enablement, CLI argument translation, xUnit.net v3 filter migration (--filter-class, --filter-trait, --filter-query), Directory.Build.props and global.json configuration, CI/CD pipeline updates, and MTP extension packages. DO NOT USE FOR: migrating between test frameworks (MSTest/xUnit/NUnit), xUnit.net v2 to v3 API migration, MSTest version upgrades (use migrate-mstest-* skills), TFM upgrades, or UWP/WinUI test projects.

Validates custom dotnet new templates for correctness before publishing. Catches missing fields, parameter bugs, shortName conflicts, constraint issues, and common authoring mistakes that cause templates to fail silently. USE FOR: checking template.json files for errors before publishing or testing, diagnosing why a template doesn't appear after installation, reviewing template parameter definitions for type mismatches and missing defaults, finding shortName conflicts with dotnet CLI commands, validating post-action and constraint configuration. DO NOT USE FOR: finding or using existing templates (use template-discovery), creating projects from templates (use template-instantiation), creating templates from existing projects (use template-authoring).

Calculates targeted CRAP (Change Risk Anti-Patterns) scores for a named .NET method, class, or single source file. Use when the user explicitly asks to compute CRAP scores or assess risky untested code for a specific target, combining Cobertura coverage data with cyclomatic complexity analysis. DO NOT USE FOR: project-wide coverage analysis, coverage plateau or "stuck coverage" diagnosis, what's blocking coverage, or where to add tests across a project (use coverage-analysis); writing tests; running tests without CRAP context.

Mechanically replace static dependency call sites with wrapper or built-in abstraction calls across a bounded scope (file, project, or namespace). Performs codemod-style bulk replacement of DateTime.UtcNow to TimeProvider.GetUtcNow(), File.ReadAllText to IFileSystem, and similar transformations. Adds constructor injection parameters and updates DI registration. USE FOR: replace DateTime.UtcNow with TimeProvider, replace DateTime.Now with TimeProvider, migrate static calls to wrapper, bulk replace File.* with IFileSystem, codemod static to injectable, add constructor injection for time provider, mechanical migration of statics, refactor DateTime to TimeProvider, swap static for injected dependency, convert static calls to use abstraction, replace statics in a class, migrate one file to TimeProvider, scoped migration, update call sites. DO NOT USE FOR: detecting statics (use detect-static-dependencies), generating wrappers (use generate-testability-wrappers), migrating between test frameworks.