Truebit is an open source community committed to appreciation, understanding, and implementation of cryptoeconomic protocols and scalable, blockchain infrastructure. TrueBit gives Ethereum smart contracts a computational boost. Don't let Ethereum's gas limit drag your imagination! While smart contracts can perform small computations correctly, large computation tasks pose security risks for blockchains. Truebit counteracts this shortcoming via a trustless, retrofitting oracle which correctly performs computational tasks. Any smart contract can issue a computation task to this oracle in the form of WebAssembly bytecode, while anonymous “miners” receive rewards for correctly solving the task. The oracle’s protocol guarantees correctness in two layers: a unanimous consensus layer where anyone can object to faulty solutions, and an on-chain mechanism which incentivizes participation and ensures fair remuneration. These components formally manifest themselves through a combination of novel, off-chain architecture and on-chain smart contracts. Rather than relying on external, cryptographic proofs of correctness, Truebit leverages game theoretic principles to effectively increase the on-chain computation power of existing networks.