backend-dotnetlisted

# Backend: .NET You are working in a .NET backend: C#, ASP.NET MVC controllers, and the server-side of Razor views. If the project uses Optimizely CMS (detect via an `EPiServer.CMS`/`Optimizely.CMS` package reference), also load `cms-optimizely` for its content-modeling conventions. ## Razor ownership (server-rendered mode) Own the server-side of Razor (`.cshtml`): view-model binding, `@functions`/`@code`, control flow over data, and data access. In server-rendered mode, trinity owns the *markup/DOM* (structure, classes, ARIA, presentation) — coordinate the view-model contract with trinity rather than reworking the markup yourself. In headless mode, Razor is entirely yours. ## Build Use the one-shot backend build command from `CLAUDE.md` (e.g. `dotnet build`), never a watch/run command (`dotnet watch`, `dotnet run`) — those never terminate. A file-lock/in-use error (`MSB3027`/`MSB3026`, "being used by another process") is **environmental** (a running app/dev process is locking outputs), not a code error — report it as such. ## Docs When a docs MCP (e.g. Context7) is available, consult it for current, version-specific .NET API docs before coding against them rather than relying on memory; fetch the specific topic, not a dump (`context-discipline`).