AlphaCodium is an open-source code generation system from CodiumAI (now Qodo), released on GitHub with roughly 4,000 stars. It is the official implementation of the AlphaCodium paper, which showed that a carefully designed multi-stage flow beats direct prompting by a wide margin on hard coding benchmarks.
Instead of asking a model for code in one shot, AlphaCodium moves through structured stages: it reflects on the problem, reasons about inputs and outputs, generates and ranks test cases, produces candidate solutions, and then iteratively runs, debugs and fixes them against the tests. On the CodeContests benchmark, this flow engineering lifted GPT-4’s pass rate from 19% to 44% without any model fine-tuning. The repository includes the full pipeline, configuration for running it on CodeContests and other datasets, and the prompts used at each stage, making it a reference implementation for test-driven, agentic code generation. The code was last updated in 2024.
AlphaCodium is free and open source under the AGPL 3.0 license. There is no paid edition of the tool itself; you only pay for the underlying model API calls you choose to run it with.
AlphaCodium is for researchers and engineers working on code generation who want to study or reuse a proven flow-engineering approach for squeezing far better results out of existing models.