Ethereum smart contract ERC20 for Pre-ICO & ICO Phase

GENERAL: Experience in creating complex smart contracts on Ethereum platform is needed. Should have prior experience in initial coin offering projects and blockchain based products. ENVIRONMENT: Solidity, Ethereum Virtual Machine (EVM), NodeJS, Geth, TestRPC, Truffle v4, Atom, web3 JS API, MetaMask/MIST, Html, Css, Javascript frameworks, SQL Server 2012 SPECIFIC: - Design, develop & test the Dapps built using Webpack Truffle boxes & front-end technologies. - Use Ethereum contract design patterns (such as Self-destruct, race condition, safe math Factory, Name registry, Mapping Iterator, etc.). - Built, deploy and thoroughly test the smart contracts in various test environments – TestRPC, Geth private network and Ropsten test network/acceptance environment. - Use Atom & Truffle’s Mocha Javascript testing framework & Chai behavior driven development assertions in TestRPC to test various test cases of test suite. - Develop & test the token creation & token distribution smart contracts. For crowd-sale contract, develop & test the contribute, refund, funding status and payout functions. TASKS: 1. Smart contracts -Pre ICO & ICO Phase -Token creation -Token distribution against incoming Ether address - Ether current price based calculation to find how much token to be send to an incoming ETH payment - In Pre-ICO stage there will be sale with 20-30% free token on each purchase. 2. Token Distribution for Bounty/AirDrop/PR campaigns, Somthing like - there will be a list of wallet addresses in database, we might be sending tokens to that list of addresses. 3. Integration with ICO website through web3 JS API 4. TESTING TESTING & TESTING [login to view URL] should be listable in any exchange Please share your experience on these skills and present reference implementations in your proposal. It will be a long term work, if worked then you can work with us on our product dapp.