Expr Playground provides a simple and user-friendly interface to write and quickly evaluate Expr expressions.

expr-lang ➡ SQL translator

A terminal spreadsheet that feels like a spreadsheet.

A simple language of expressions.

Browser-based editor for the Expr expression language with live eval, formatting, and AST inspection — all client-side via Go WASM

A high-performance, generic Rules Evaluation Engine for e-commerce promotions using Google CEL (Common Expression Language). Unlike traditional systems that hardcode promotion logic, Price-Cutter allows dynamic, runtime definition of complex promotion rules.

make expr-lang be embedded easily in Golang

General-purpose JSON/JSONC programming language engine in Go. 20 step types, 135+ functions, lambda expressions, structs, I/O modules, web server.

RuleTrace: small explainability layer for expr-lang that records rule eval traces

Pilot Protocol policy plugin + policy expression language (expr-lang/expr backed)

parse react query builder JSON into expr lang expressions

Make HTTP requests from inside WASM in Expr. Demo and devcontainer.

Kubernetes admission webhook, audit loop, and NetworkPolicy analyser. Rules are boolean expressions (expr-lang/expr) — no DSL.