New Solidity compilers arrive with major speed gains for Ethereum developers

Ethereum developers just got two reasons to update their toolchains. Within days of each other in September 2026, the Nomic Foundation shipped slang-solx, a new LLVM-based Solidity compiler backend, and the core Solidity team released v0.8.37 with security fixes and fresh opcode support. The bigger headline belongs to slang-solx. Launched on September 7, the compiler backend achieves speeds up to 5x faster than the traditional solc compiler when running in via-IR mode, and roughly 1.7x faster in legacy mode. What slang-solx actually changes Slang-solx attacks the problem at the backend level by leveraging LLVM, the same compiler infrastructure that powers Clang for C/C++ and Rust’s compiler. The project traces back to a compiler effort called solx that Matter Labs initiated in 2025. At some point the work transitioned to the Nomic Foundation, the organization behind Hardhat, Ethereum’s most popular development framework. Currently, slang-solx supports Solidity 0.8.34 and is explicitly positioned for development use rather than production. Nomic is not recommending it for mainnet deployments yet. The 5x speed improvement in via-IR mode is particularly noteworthy because via-IR is th...