Please list the technologies used by the company that published the following vacancy:

Covalent is redefining how top industrial companies are qualifying their workforces and utilizing workforce data. We’re looking for an exceptional Ruby on Rails engineer to join us in building that adds value to employees, companies and the industrial ecosystem.
As a Ruby on Rails Engineer, you will deliver solutions as we continue to maintain and expand on our core application, and will have the opportunity to be a technical thought leader in the building of new products as we look to expand the Covalent platform.
Our ideal candidate has strong expertise in software development principles, is excited to accept ownership of features and deliverables, has excellent verbal and written communication skills, and is enthusiastic about growing with an evolving new business. This is a fast-paced startup environment, candidates should be interested in working in a dynamic, agile engineering culture.
Given the industries we serve, this position must meet Export Control compliance requirements, therefore a “US Person” as defined by 22 C.F.R. § 120.15 is required. “US Person” includes a US Citizen, lawful permanent resident, refugee, or asylee.
This position is contract to hire. 
Responsibilities: 

    Write concise and maintainable code in Ruby on Rails, SQL and Javascript.
    Help improve code quality through writing unit tests, E2E tests and performing code reviews.
    Work collaboratively with the rest of the scrum team (Engineering, QA and Product) to deliver features and bug fixes within a scrum framework.
    Be a thought leader within the Engineering team and the larger organization.

Requirements
Required experience:

    5+ years of web application development
    3+ years of Ruby on Rails 
    3+ years of SQL experience (Postgres preferred)
    2+ years of Javascript framework experience (React & Redux preferred)
    Git source control experience
    Strong communication skills around requirements, user stories and technical challenges


Nice to have:

    Scalable data architecture experience
    Experience integrating with other applications
    The ability and desire to mentor other engineers
    Strong technical documentation skills
    Test-driven development experience

Benefits
Why join us?
Our team is passionate about helping people gain in-demand skills that drive economic independence. To do so, we provide purpose-built software for technical training and workforce analytics in industrial environments. Our platform  Please repeat the request first, then give your response.
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