Senior Full Stack Software Engineer Jobs in Mercer Island, WA

System1 (NYSE: SST) is an omnichannel customer acquisition marketing platform powered by AI and machine learning. Our proprietary Responsive Acquisition Marketing Platform (RAMP) uses data science and real-time bidding to match high-intent consumers with advertisers at scale. We operate a portfolio of consumer-facing brands across search, shopping, and travel - including Startpage, MapQuest, and CouponFollow - and build the apps, search engines, and online publications that power them.
Startpage (part of System1) is the world's most private search engine. We deliver high-quality search results through a privacy-preserving proxy layer that strips identifying information before queries leave our infrastructure. Users get the search experience they expect without being tracked, profiled, or targeted.
Startpage is looking for a full-stack Senior Software Developer to work alongside our existing team. This is a full-time, on-site position with the expectation of a 40-hour work week from our Bellevue, WA office.
At a high level, Startpage engineers work with our product team to build out new features on our roadmap, primarily for our private search engine, our flagship product. We also help to shape architectural decisions, while proactively tackling tech debt, bugs, and other engineering tasks. All developers at Startpage work with a wide variety of languages, tools, and technologies across all parts of the stack. Generally, day-to-day work across our stack includes mostly Python and JavaScript.
We are a small but fast-moving, adaptable team, and we are rapidly iterating our products to meet the ever-changing demands of the open internet in the world of AI. The team is distributed across time zones in North America and Europe. While we don't maintain a strict schedule, everyone on the team overlaps their days for 4-5 hours so we can all work together for a portion of our day.
Ideal candidates for this role are self-starters who take initiative and learn things quickly, are flexible in dealing with rapidly evolving technical requirements, and have a good eye for balancing quality, output volume, and complexity. Startpage developers are expected to oversee their work from tickets to production deployments and monitoring, and should feel confident and comfortable releasing changes to a highly-trafficked, internationally distributed web product multiple times per week.
Given Startpage is a privacy-focused product, previous experience working on a privacy-focused web product would be an asset, but is not a hard requirement. Similarly, our developers are expected to have a high level of attention to detail in order to maintain the privacy of our users, which we take very seriously. Engineering at Startpage means working on systems where privacy is a real architectural constraint, not a marketing line. This role also requires participation in our emergency on-call rotation.
This position is a hybrid role requiring you to work out of our Bellevue, WA office located at 10800 NE 8th Street Suite 200 Bellevue, WA 98004.
Technical Qualifications and Desired Experience:

• Excellent communications skills, strong command of the English language
• 5+ years of professional software development experience building and operating production web services at scale.
• Deep understanding of HTTP and all of its moving parts: front-ends, back-ends, serving infrastructure, DNS, etc.
• Good understanding of REST API architectures, both writing them and consuming them.
• Experience with JavaScript (TypeScript/Node.js/React), modern CSS, and HTML.
• Experience with Python-our backend services are predominantly written in Python.
• Hands-on experience with Kubernetes and Helm in a multi-region production environment and a good working knowledge of K8s concepts.
• Proficient with Docker and containerized service development.
• Experience with Redis and/or similar caching strategies in latency-sensitive systems.
• Comfortable with modern CI/CD tooling (ArgoCD, GitHub Actions).
• Experience with monitoring and instrumenting services such as New Relic, Datadog, Cloudwatch, etc.
• Strong automated testing experience and discipline (unit, integration, and end-to-end tests).
• Experience with AI coding tools and a good understanding of when it is appropriate to move quickly with these tools versus when it is important for human oversight.
• Experience with AWS or other modern cloud provider(s) for serving well-architected, scalable web applications.
• Any background or previous experience in search, ad tech, or browser-facing privacy products would be an asset but not a must.

What We Have To Offer:

• Competitive salary + bonus + equity
• Generous PTO + 11 company holidays
• Open sick time
• 100% covered Medical, Dental, Vision for employees
• 401k with match
• Health & Dependent Care Flex Spending Account
• Paid professional development
• Leadership & growth opportunities
• Virtual company and team building events

The U.S. base salary range for this full-time position is $133,000 - 170,000 + bonus + equity + benefits. Our salary ranges are determined by role, level, and location. The range displayed on each job posting reflects the minimum and maximum target for new hire salaries for the position across all US locations. Within the range, individual pay is determined by work location and additional factors, including job-related skills, experience, and relevant education or training. Your recruiter can share more about the specific salary range for your preferred location during the hiring process. Please note that the compensation details listed in U.S. role postings reflect the base salary only, and do not include bonus, equity, or benefits.
System1's headquarters is located in Marina del Rey, CA with an additional office in Bellevue, WA.
Employees near office locations are returning to the office.
Equal Employment Opportunity:
System1 provides equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.
This policy applies to all terms and conditions of employment, including recruiting, hiring, placement, promotion, termination, layoff, recall, transfer, leaves of absence, compensation and training.
We may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses and identifying potential inconsistencies or verification signals in application materials based on available information. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.