1.
Short introduction from my side and the recruiters side as well. Suddenly he switched to tech questions like: What is DDD, CQRS, ACID, SOLID, Concurrency, locking.
He asked me about my experiences and how I assure code testability overall.
2.
For the coding challenge you need to have an IDE open with a new project. The interviewer sends the requirements via chat and you need to start coding the solution right away.
The requirements are easy overall but you need to take care about coding speed, maintainability, testability (solid principles) and write unit tests for the given scenarios to assure code quality. It is not an easy task to do it right so you need full focus to pass.
3.
This round was unfortunately the last one for me though I really liked the whole interview process at Revolut. I was prepared for Solidity coding and smart contract deployment and testing but it was not necessary at all. The interview was 100% theoretical and blockchain related. They asked about cryptocurrencies, what is a cryptocurrency? What is oraclization? Smart contract testing and decentralised application testing, consensus algorithms, Ethereum 2.0 - Proof of stake. How would you design a backend service to communicate with a smart contract, what would be the architecture?
The interview was very intensive with a lot of technical questions regarding blockchain and if you are not certain with even only 1 or 2 of your answers you won't pass. (Thats what happened to me) You need to be 100% certain and have very deep understanding about everything related to blockchain technologies and development.