Building a Native C# Implementation of the CEL Engine for .NET
Building a native C# implementation of CEL engine
I built Celly, a pure managed C# implementation of Google's Common Expression Language that passes the full conformance suite. By avoiding WebAssembly or native bindings, I created a safe, high-performance policy engine for .NET. This project also enabled the first protovalidate library for the platform, allowing developers to enforce validation rules directly in their applications without redeploying code.
The trick is that CEL gives you just enough language to express real logic and deliberately withholds everything that would make it dangerous.