At Segment, we believe companies should be able to send their data wherever they want, whenever they want, with no fuss. Unfortunately, most product managers, analysts, and marketers spend too much time searching for the data they need, while engineers are stuck integrating the tools they want to use. Segment standardizes and streamlines data infrastructure with a single platform that collects, unifies, and sends data to hundreds of business tools with the flip of a switch. This empowers our customers to focus on building amazing products and create personalized experiences for their customers, while we take care of the complexities of processing their customer data reliably at scale. With an incredibly sticky product and minimal direct competition, we’re on track to be the driving force behind powering the entire customer data ecosystem, which brings us to you.
The Libraries and Instrumentation team builds software that brings more than 2 billion events at greater than 1 million requests per second into Segment from millions of devices so that we can make rich data accessible to our customers. From startups to Fortune 100, businesses of all sizes rely on the Segment Platform to deliver data downstream into hundreds of streaming integrations and thousands of customer data warehouses. Instrumentation is the gateway to getting all data into Segment, which enables us to deliver amazing digital customer experiences.
While our analytics.js library has been around since day one, we believe it is time for us to make a step-change around how our customers add analytics to their applications and build the next generation of our instrumentation platform. This means we need to go deep and think about how applications are built, how their runtimes operate, as well as improve the developer experience of integrating with Segment.
We are looking for a software engineer with expert-level Javascript experience to help craft a high-performance and highly operable Javascript library that will be used by web developers like you to integrate their applications with Segment. Your code will run on all Segment customer’s website and will be responsible for collecting analytics. Therefore, the code should be performant, well-tested, well-documented, and fault-tolerant. 

Who we’re looking for:

  • You love writing code in Typescript/Javascript and know the language and ecosystem really well. 
  • You enjoy writing reusable libraries and SDKs that will be used by other developers
  • You enjoy writing code that runs on browsers, lower in the stack than frameworks like React or Vue
  • You are willing to keep up with the latest changes in the web ecosystem 
  • You care about writing code that is optimized for performance and can run in a variety of browsers, and conditions
  • You value and enjoy being part of a cohesive and supportive team.
  • You are passionate about helping your team find scalable solutions to challenging technical problems.
  • You know when it’s time to refactor and when it's time to ship.


  • You have 4+ years of engineering experience writing Javascript for client-side web or mobile runtimes
  • You are familiar with TypeScript, modern Javascript language features, and tooling 
  • You have experience debugging complex issues in a variety of browsers
  • You have experience measuring and optimizing the performance of web applications or libraries
  • Experience maintaining and contributing to open source projects.
  • Nice to have: worked in a professional environment on scalable, cloud-based distributed systems.
  • Nice to have: experience writing Node.js applications.
We encourage you to apply if this role excites you - even if you think you may not meet all of the qualifications. At Segment we live by four values: karma, drive, tribe and focus. We are always looking for outstanding individuals with diverse backgrounds and perspectives who embody these values. To learn more about life at Segment and our commitment to diversity, equity, and inclusion, visit our LinkedIn page. We’re excited to meet you!
Segment is an equal opportunity employer. We believe that everyone should receive equal consideration and treatment in all terms and conditions of employment regardless of sex, gender (including pregnancy, childbirth, breastfeeding or related medical conditions), sexual orientation, gender identity, gender expression, race, color, religion, creed, national origin, ancestry, age (over 40), physical disability, mental disability, medical condition, genetic information, marital status, domestic partner status, military or veteran status, height, weight, AIDS/HIV status, and any other protected category under federal, state or local law. Pursuant to the San Francisco Fair Chance Ordinance, we will consider for employment qualified applicants with arrest and conviction records.

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