developer-apis enterprise-software telephony
San Francisco, CA

Sr Software Engineer - Proxy


Twilio Engagement Cloud is a suite of declarative APIs that handle the communications logic needed for every type of customer engagement.Our mission is to give builders preconfigured, smart, and nuanced building blocks that allow them to leverage the power of the Twilio platform while focusing on the user experience.  

Proxy is the all-in-one answer to one of Twilio’s most common uses - private text and voice conversations between a customer and a mobile worker representing your business. Proxy connects riders & drivers, guests & hosts, shoppers & delivery.

About the job:

As a senior engineer at Twilio, you are empowered to create wonderful experiences for our customers, developers just like you. You are excited when you release something that makes developers' lives better.

You think about the largest customer currently using Twilio and the future largest customer who just signed up yesterday.

 You will own and create REST APIs for customers to create and configure Twilio Proxy services that will orchestrate the messaging and voice traffic of some of our most interesting customers. To take Twilio Proxy to scale, you will be developing a complex distributed platform and will be concerned with availability, throughput, latency and real-time responsiveness.

 You will build services that intelligent handle error conditions and carefully choose how and when to surface them to the developer.

 You will own and operate production services in AWS cloud infrastructure using the latest tools, like Datadog and Rollbar.

 You will work in a small and empowered team. During the day, you will work on large new complex features that encompass multiple sprints. You will also push small impactful fixes multiple times a week for quick wins. Senior Engineers are critical in making sure Twilio is loved by developers, is easy and fun to use, and stays on the cutting edge.

You can make a developer's life better.


  • Continue to develop and scale the Twilio Proxy product.
  • Collaborate with Product Managers, Architects and Engineering leaders to define, architect and build new customer-facing features.
  • Own, operate, and maintain your team’s services in a distributed production environment.  You own what you build, from your desktop to production.
  • Drive quality by writing unit, functional, load and performance tests.
  • Work closely with DevOps engineers to ensure services are reliable, scalable, manageable and supportable.
  • Excel as an engineer and be a productive member of the team where leadership is a behavioral trait, not a title.  Lead architecture, design and code reviews as well as mentor junior engineers.


  • Bachelor’s degree in CS or similar field, or related work experience.
  • Prior experience as Senior Software Engineer.
  • Extensive experience scaling production backend systems.  You can design and develop horizontally-scalable, resilient and performing-under-load systems.  You have scaled data tiers employing a variety of SQL/NoSQL database and caching technologies.
  • Java or JVM language experience preferred. You are an expert in at least one web stack and framework.
  • Experience of agile processes, continuous integration and test automation.

Bonus points:

  • You've worked with Twilio products and can think of ways to improve them.
  • You’ve worked with voice or messaging communications products.
  • You know the difference between an Abstract Base Class and an Interface, and when to use them.
  • You have tuned a production service based off of customer feedback and empirical data.
  • You have spent 4 hours figuring out what 4 characters are causing a bug and kind of liked it.
  • You have worked in both a monolithic and heavily service oriented architecture and understand the benefits of each.
  • Experience with build/deployment tools such as Maven, Chef and Jenkins.

About us

Twilio makes communication easy and powerful. Over 700,000 web and mobile developers have used Twilio’s cloud-based platform to integrate voice, SMS and MMS capabilities into software applications. Customers like Uber, Airbnb, Box and Home Depot leverage Twilio’s well-documented REST interface to power and innovate their communications at global scale. Twilio is recognized as one of the 10 Fastest Growing Companies in San Francisco, one of The Bay Area’s 10 Most InDemand Startups, and has over 400 employees with offices in San Francisco, Mountain View, New York City, Bogota, Tallinn, Dublin, London and Hong Kong.

Twilio is proud to be an equal opportunity workplace and is an affirmative action employer. We are committed to equal opportunity regardless of race, color, ancestry, religion, gender, gender identity, parental or pregnancy status, national origin, sexual orientation, age, citizenship, marital status, disability, or Veteran status and operate in compliance with the San Francisco Fair Chance Ordinance. #Li-Post


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