# Fast, portable, non-Turing complete expression evaluation<p>Common Expression Language (CEL) is a non-Turing complete language designed for simplicity, speed, safety, and portability. CEL is designed to be evaluated without a sandbox, making it ideal for use within latency critical applications.<p>## Features<p><pre><code> - Familiar C-like syntax common to C++, Go, Java, and TypeScript.
- Gradual typing with first-class support for Protobuf and JSON types.
- High performance evaluators in C++ and Go with a rich set of standard operators.
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## How Google uses Common Expression Language<i></i><p>Google uses CEL as the expression component of IAM and Firebase security policies, as well as within Istio Mixer configs.