FlexiTime Token: Building dApps with Ethereum

Problem: A company wants to retain the services of a consultant for a total of 16 hours over a 12 month period. It’s often the case that budget must be approved latest by beginning of Q1, and any budget not spent by end of Q3 gets cut, yet consultant’s services are often most needed in Q4. So company can pre-buy consultant’s time by paying for it in Q1 and then drawing down the hours during the year. Usually both company and consultant keep a spreadsheet of allocated and spent time, and reconcile every quarter or so, sometimes having to handle disputes.

Solution: Track pre-bought time as tokens on blockchain. Tokens can be redeemed for time by sending them to a task escrow contract address, and then on to the consultant once a task has been completed. Since code and data are immutable neither the consultant nor the company can alter either the code nor the balances without following agreed logic.

Implementation: Write a dApp in Ethereum. This includes (a) smart contracts written using the truffle framework, (b) user interface written in Angular 2 using the wed3 lib to interact with ethereum, and (c) off-chain private data storage protected by JWTs that are generated using signed by Ethereum private key messages. Will be able to demo how the solution works, how the dApp is architected, and key code highlights of contracts, UI code, and the private data store (uses Swagger, JWT, node.js, express).