We have decided to open source our implementation of pooled mining for Ethereum. This software is not a complete mining pool. It only takes care of work distribution and share validation; valid shares are stored into a local database (LevelDB). Reward calculation and payments are not yet implemented but it should be possible to connect this software some of the existing open source mining pools.
While the current implementation in go might not be the most effective one, the pool was able to process ~600 workers at 30% CPU utilization (1 core) and 70MB RAM usage.
The pool has been tested successfully with both the go Ethereum client (geth) and the cpp Ethereum client (eth).
Pull requests & possible optimizations
If you find any issues with the pool software please feel free to issue a pull request.
If you want to improve the pool, implementing the connection to geth via IPC instead of HTTP would be a good start.