Java project to connect to Bitcoin Blockchain

General information for the business: Involved in Cryptocurrencies
Kind of development: New program from scratch
Num. of modules: 2
Description of requirements/functionality: The following project shall be done with Java and a library facilitating use of the bitcoin protocol (most likely BitcoinJ). The project consists of two modules
1. Use BitcoinJ to connect to the blockchain and receive new updates. We want the ability to use ReactiveX (rxjava) to subscribe to:
- transactions above a certain amount
- transactions from or to a certain wallet adress

2. Use BitcoinJ (or any other protocol) to connect to a large number of nodes, whenever a new block is broadcast from one of these nodes, we want the local timestamp, the block number, and the hash to be recorded in a local database. The block itself does not need to be saved, since this is covered in module 1. This modules incentive is to be as sure as possible about the real timestamp of a new block. The higher the number of nodes we connect to, the higher the likelihood of getting a new block quicker.

We want the whole project to be created using TDD (but with TestNG instead of JUnit). We prefer clean code over quick "elegant" hacks, and we require it to be safe in terms of concurrency issues. The source code shall be Java 8 compliant.

If the project is a success and well within our standards, there will be offers of follow up projects.

If you contact us, please tell us how experienced you are in the respective fields (Java, TDD) and in general related technologies, as well as provide some information about previous projects you did or technologies you used.
Specific technologies required: Java, ReactiveX (RxJava), TDD
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