Senior Ruby on Rails developer needed for full-time employment

Needs to hire 4 Freelancers. We are hiring elite (top 1%), quality-focussed software engineers, who can deliver highly maintainable and agile code. Experience with good software architecture practices, and the ability to express correct solutions without compromising the long term maintainability of the software system are a requirement for this position, and will be tested during the interview. This is a long term full-time position centered around Ruby and JavaScript development, but may branch into other technologies such as Python, Java, Kotlin, and F#. Requirements - Full-stack Ruby on Rails + JS developer, minimum 5 years experience - Great programming and analytical skills (do not apply if you are not an elite, top 1% developer) - Proficient in high quality code architecture: we need DRY, modular, highly decoupled code that follows SOLID principles - Experience writing extremely high performance software, low latency rails apps, and high throughput data processing systems - Minimum 5 years experience with MySQL and PostgreSQL - Heroku, Linux experience - Proficient with Git & Github - Strong English speaking skills - Ability to own projects end-to-end - Attention to detail - Minimum 100 hours on Upwork Bonus Skills & Experience - Java or Kotlin programming experience - Python programming experience - F# programming experience - You have read Sandi Metz' Practical Object-Oriented Design in Ruby, and implemented the discussed principles (or similar) in your code - Machine Learning / Data Science experience - Startup experience To show that you have read this application carefully, please write "Edsger Dijkstra" at the top of your cover letter, and make sure you answer all questions as fully as possible to be considered for this job. We have 4 open positions and will hire every top engineer who meets our high standards. 1. How many years of experience do you have with each of the following: Ruby, Rails, Python, Java, Kotlin, F#? How would your rate your written and spoken English skills? 2. What are your 3 favorite books on Ruby or Rails? (bonus points for books related to code organization and architecture) Are you familiar with TDD? What is it? Explain. 3. What are some common principles and patterns used to achieve clean, high quality, maintainable code? 4. Describe 3 design patterns which you personally frequently use. 5. What does SOLID stand for? Explain what each letter in the acronym means, and how and why the rule is used.