Principal Software Engineer
OpenX
Software Engineering
United States · Remote
Posted on Aug 19, 2025
OpenX is focused on unleashing the full economic potential of digital media companies. We do this by making digital advertising markets and technologies that are designed to deliver optimal value to publishers and advertisers on every ad served across all screens.
At OpenX, we have built a team that is uniquely experienced in designing and operating high-scale ad marketplaces, and we are constantly on the lookout for thoughtful, creative executors who are as fascinated as we are about finding new ways to apply a blend of market design, technical innovation, operational excellence, and empathetic partner service to the frontiers of digital advertising.
We’re seeking a Principal Engineer to lead the architecture, development, and technical direction of products within our SaaS platform. You’ll join a talented, remote-first US team and play a pivotal role in shaping the platform. This is a strategic and hands-on role where you will write production code, build and modernize the frontend, and design and scale APIs. You’ll mentor senior engineers, and ensure the architecture enables rapid iteration, massive scale, and long-term reliability.
An ideal candidate is:
* Open-minded – Welcomes feedback, learns from failure, and adapts quickly to change.
* Proactive – Takes initiative to identify problems and drive thoughtful, effective solutions.
* Self-motivated & Organized – Manages priorities independently and follows through with clarity and accountability.
Key Responsibilities:
- Lead and contribute to the development of the platform and its frontend, ensuring scalability, fault tolerance, high throughput, and long-term reliability.
- Design, implement and optimize low-latency services, APIs and modern frontend features that deliver a high-quality customer experience.
- Drive critical platform and frontend initiatives from design and prototyping through implementation, testing, rollout, and adoption.
- Identify and address technical debt, performance bottlenecks, and scalability risks before they impact customers.
- Champion architectural patterns and platform capabilities that improve developer velocity and operational reliability.
- Provide technical leadership by example: pair programming, leading design sessions, reviewing code, mentoring engineers, and fostering a culture of excellence.
Required Qualifications:
- 12+ years of professional software development experience, with strong proficiency in modern frontend languages (e.g. React, TypeScript) and a track record of building scalable systems using backend technologies such as Python, Go or Java.
- Experience building and modernizing complex SaaS frontends with a focus on maintainability, usability, accessibility, and performance.
- Hands-on experience with a major cloud platform (GCP, AWS, or Azure) for designing and operating production workloads.
- Proven track record of delivering distributed, high-performance, and highly reliable systems that operate at scale.
- Expertise in designing and scaling APIs (RESTful, gRPC, Thrift), including data modeling, error handling, performance optimization, and security best practices.
- Experience leading architecture and technical direction across multiple teams or product areas.
- Strong problem-solving skills, with the ability to anticipate and address scalability, reliability, and privacy challenges.
- Excellent collaboration and communication skills, with success working closely with product, engineering, and cross-functional stakeholders.
- Proven ability to mentor senior engineers and raise technical standards across an organization.
Preferred Qualifications:
- Experience designing real-time, low-latency, large-scale data processing systems.
- Knowledge of programmatic advertising or other high-throughput transactional platforms.
- Familiarity with CI/CD pipelines, infrastructure as code (Terraform, Helm), and advanced monitoring/observability tools (e.g. Grafana).
- Proven ability to introduce architectural patterns that improve developer velocity and system reliability.
- Experience using AI-assisted development tools to enhance productivity.