Truebit allows software running outside a blockchain environment to provide trusted results to smart contracts and applications running within a blockchain. The platform allows practically unlimited external compute resources to be applied in a trusted way to extend the performance, throughput, and scalability of its host blockchain. Research began in 2015 on this verification solution which today connects blockchains to both on-chain and off-chain data while enabling smart contracts to securely perform complex computations in standard, easy-to-use programming languages at significantly reduced gas costs.  
Unlike sharding and other methods for distributing high transaction throughput, Truebit processes complex and large transactions via a consensus mechanism involving a minimal number of redundancies, making it a novel solution for Web 3.0 infrastructure. The bulk of computation occurs with off-chain resources. 

Truebit Whitepaper