Senior Software Engineer, Core



Software Engineering
United States · Remote
Posted on Friday, March 17, 2023

OneSignal is a leading omnichannel customer engagement solution, powering personalized customer journeys across mobile and web push notifications, in-app messaging, SMS, and email. On a mission to democratize engagement, we enable over a million businesses to keep their users - including readers, fans, players and shoppers - engaged and up to date by delivering 12 billion messages daily.

1 in 5 new apps launches using OneSignal! We support companies in 140 countries, including Zynga, USA Today,, Upwork, Tribune, and many more - from startups and small businesses just getting off the ground to established companies communicating with millions of customers.

We’re venture-backed by SignalFire, Rakuten Ventures, Y Combinator, HubSpot, and BAM Elevate (read more about our recent Series C!). We’re a remote-first company, offering remote work as the default option in the United States in California, New York, Pennsylvania, Texas, and Utah as well as in the UK and Singapore - with plans to expand the locations we support in the future. We also have offices in San Mateo, CA, New York City, and London, UK. Hiring in Singapore is done in partnership with a local PEO.

OneSignal has a lot of the great tech startup qualities you'd expect, but we don't stop there. Our massive scale and small team, emphasis on healthy life balance and kindness in all our interactions, and focus on ownership and personal growth make OneSignal a uniquely great place to work.

About The Team:

OneSignal has grown rapidly to where we are today serving billions of HTTP requests daily and sending upwards of over 10 billion messages daily. We achieved this scale by leveraging bare metal cloud and writing scale sensitive components in languages like Rust and Go. This potent combination of high-performance, low-cost hardware with efficient resource utilization has given us an incredible competitive edge.
We are hiring Core Engineers to help us continue to scale by operating and engineering the future of our internal services. We are investing to ensure we maintain high uptime as the business continues to grow and as the product evolves.
Your primary task will be writing software and running that software in a production environment. You'll be building systems to run our product, improving internal services, and advising product teams on architecture as it relates to the operability of the service.
Core engineers are responsible for writing, operating, and maintaining internal services that perform data access, analytics rollup jobs, and serve as the core of OneSignal’s event-driven features. We currently operate multiple gRPC services written in Go and Rust, and many Kafka consumers write in Rust. These services talk to multiple different types of backing data stores such as Redis, PostgreSQL, and Scylla.

What You'll Do:

  • Troubleshoot and repair an issue with items getting dispatched from Kafka
  • Assist the support team in determining if a customer report indicates a bug in our system
  • Help evaluate a new storage technology to further scale our stack
  • Build in automated limits on a service to prevent abuse
  • Architect a new service to scalably provide abstracted access to objects
  • Respond to production incidents in an on-call rotation

What You'll Bring:

  • At least 5 years experience working as a software engineer
  • Experience operating reliable production systems at scale
  • Easily bored running tasks by hand and the ability to automate such tasks
  • Experience with PostgreSQL

We value a variety of experiences, so these are not required. It would be an added bonus if you have experience in any of the following:

  • Experience deploying software on Kubernetes
  • Recent experience writing Go and/or Rust
  • Experience writing gRPC services
  • Past experience writing and running code in a large production environment
  • Experience with any of Redis, Kafka, Scylla

The New York and California base salary for this full time position is between $160,000 to $180,000. Your exact starting salary is determined by a number of factors such as your experience, skills, and qualifications. In addition to base salary, we also offer a competitive equity program and comprehensive and inclusive benefits.

Qualities we look for:

  • Friendliness & Empathy
  • Accountability & Collaboration
  • Proactiveness & Urgency
  • Growth Mindset & Love of Learning

In keeping with our beliefs and goals, no employee or applicant will face discrimination/harassment based on: race, color, ancestry, national origin, religion, age, gender, marital domestic partner status, sexual orientation, gender identity, disability status, or veteran status. Above and beyond discrimination/harassment based on 'protected categories,' we also strive to prevent other, subtler forms of inappropriate behavior (e.g., stereotyping) from ever gaining a foothold in our office. Whether blatant or hidden, barriers to success have no place in our workplace.

Applicants with disabilities may be entitled to reasonable accommodation under the terms of the Americans with Disabilities Act and certain state or local laws. A reasonable accommodation is a change in the way things are normally done which will ensure an equal employment opportunity without imposing undue hardship on OneSignal. Please inform us if you need assistance completing any forms or to otherwise participate in the application and/or interview process.

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