// the find
ethereum/aleth
Aleth – Ethereum C++ client, tools and libraries
Aleth is the old official C++ Ethereum client — full node, EVM, P2P networking, wallet, the whole stack. It was the reference C++ implementation before the Ethereum Foundation officially discontinued it. Archeological value only at this point.
The library decomposition is clean: libdevcore, libdevcrypto, libethcore, libethereum, libp2p are all separate CMake targets with clear boundaries. The RLPx handshake and ENR implementations in libp2p are well-documented reference material for the wire protocol. The testeth consensus test runner was the gold standard for EVM correctness testing across client implementations. The EVMC abstraction layer (now a standalone project) originated here and is still in use.
Discontinued and explicitly says so in the README — this is not a soft abandonment, it's a hard stop. The last meaningful protocol support stops at Berlin/Istanbul; it has no concept of proof-of-stake, the Merge, or any post-Merge EIPs. GPU mining support was already stripped before discontinuation, so even the mining path is incomplete. Building it today requires fighting a CMake + Hunter dependency setup that no longer has maintained package recipes.