Technology

• Servers

  • Database Server

    • PostgreSQL stores user data & sessions

  • REST Server

    • Rack: a Ruby web server
    • Passwordless authentication for the signup & login flow
    • Mailgun sends emails

  • Chat Server

    • Node.js: JavaScript server
    • WebSockets for two-way communication between client & server

• Clients

  • iPhone Client

    • Xcode for development
    • iOS SDK: Foundation, UIKit, etc.
    • Swift Programming Language

  • Android Client

    • Android SDK & Java

  • Web Client

    • HTML, CSS, and JavaScript