# Ethereum Foundation · Protocol · Specs

> The Ethereum Foundation Specs team maintains the specifications and reference tests for Ethereum's execution and consensus layers.

Specs is the Ethereum Foundation team that maintains the specifications and reference tests of Ethereum's execution layer (Specs [EL], ethereum/execution-specs) and consensus layer (Specs [CL], ethereum/consensus-specs). It was formed in 2026 when STEEL (Specifications and Testing for the Ethereum Execution Layer) and the consensus specs team merged.

## About Specs

- [Home](<https://specs.ethereum.foundation/index.md>): What the Specs team is and what it works on
- [About](<https://specs.ethereum.foundation/about/index.md>): Mission, collaborators and team history
- [Specs \[EL\]](<https://specs.ethereum.foundation/el/index.md>): Specs [EL]: execution layer specs, tests, tools and releases
- [Specs \[CL\]](<https://specs.ethereum.foundation/cl/index.md>): Specs [CL]: consensus layer specs, reference tests, c-kzg-4844 and releases
- [Team](<https://specs.ethereum.foundation/team/index.md>): Team members
- [Docs](<https://specs.ethereum.foundation/docs/index.md>): Entry point to the execution-specs documentation

## Blog

- [The Weld: EELS + EEST Will Become a Single Repository](<https://specs.ethereum.foundation/blog/2025-09-11_weld-announcement/index.md>)
- [Testing \`eth\_config\`](<https://specs.ethereum.foundation/blog/2025-09-15_eth-config/index.md>)
- [The Weld is Complete: Welcome to Unified Specs and Tests](<https://specs.ethereum.foundation/blog/2025-11-04_weld_final/index.md>)
- [Osaka Mainnet Testing](<https://specs.ethereum.foundation/blog/2025-11-27_osaka_mainnet_tests/index.md>)
- [Specs as Models: Applying Category-Partition Testing to Ethereum's Consensus Layer](<https://specs.ethereum.foundation/blog/2026-06-11_specs-as-models/index.md>)
- [STEEL and the consensus specs team are now Specs](<https://specs.ethereum.foundation/blog/2026-11-11_steel-is-now-specs/index.md>)