Senior Full Stack Developer - Downdetector Connect

The Opportunity: As a Senior Developer, you’ll have significant autonomy to shape how some of the world’s largest telecom operators communicate with consumers and detect issues across their networks. You’ll help evolve the platform into a proactive, intelligent system built around Observe - Think - Act workflows, designing autonomous, AI‑driven operations that surface insights, trigger actions, and streamline complex network processes at scale. You’ll work across the full stack, building intuitive interfaces in React and architecting resilient Python backend systems capable of handling massive volumes of time‑series telemetry. You’ll join a dynamic, experienced global product and engineering team, collaborating with specialists across mobile SDKs, cloud platforms, and large‑scale distributed systems, while working directly with global customers. If you’re excited by the challenge of building intelligent systems, solving complex data problems, and driving meaningful impact at global scale, this role offers the scope and technical depth to do your best work.

Key Responsibilities:

• Full-Stack Development: Develop and maintain robust, scalable web applications using React, Redux, and modern backend frameworks.
• Automation & AI Features: Move the platform from reactive reporting to proactive operations by implementing "Observe-Think-Act" loops for network outage detection and communication.
• Maintain Technical Quality: Write clean, maintainable, and efficient code while conducting high-signal code reviews to elevate engineering standards.
• Collaborate Cross-Functionally: Work closely with Product teams to translate emerging AI capabilities into high-performance features for our global operator clients.
• Scale Data Processing: Help maintain and optimize backend services capable of handling high-volume network telemetry and time-series data.
• Experience integrating third-party APIs, AI services, webhooks, and event-driven workflows into production applications.

Job Qualifications:

• 5 to 8 years of professional software engineering experience.
• Experience in mentoring or leadership.
• Strong proficiency in Python (FastAPI or Django) and experience designing scalable RESTful APIs.
• Proficient in React and Redux with hands-on experience building complex, data-heavy web applications.
• Hands-on experience using AWS to build and scale web applications, including containerization (Docker/Kubernetes).
• Systems Thinker: Strong ability to break down complex manual problems into deliverable, automated technical sub-tasks.
• PLUS: AI Frameworks: Hands-on experience deploying AI agents into production or proven exposure to tools like LangChain, LangGraph, or LlamaIndex.
• PLUS: Experience with anonymization techniques, data privacy and GDPR.
• PLUS: Domain: Understanding of network monitoring, telecommunications data, or performance testing.

About Ookla: Ookla is a global leader in connectivity intelligence, offering unparalleled network insights through the combined expertise of Speedtest®, Downdetector®, RootMetrics®, and Ekahau®. Ookla’s complementary datasets combine crowdsourced and controlled, public and private collection methods, QoS and QoE metrics, and more to unlock correlations and actionable insights — helping organizations optimize networks, enhance digital experiences, and create better connected experiences for end-users. Our team is a group of people brought together through passion and inspired by possibility. We are looking for team members who love solving problems, are motivated by challenges, and enjoy turning clever ideas into exceptional products. When you work for us, you are using Ookla data and insights to advance our mission of better connectivity for all.

Our Benefits: Ookla offers competitive salaries in addition to robust, health and wellness-focused benefits. We are committed to work-life balance with paid time off when you need it. At Ziff Davis, we remain dedicated to creating an environment where everyone feels valued, respected, and empowered to succeed. We offer Employee Resource Groups, company-sponsored events, and regular opportunities for professional growth through educational support, mentorship programs, and career development resources. Our employees are recognized and celebrated through employee engagement programs and recognition awards. If you're seeking a dynamic and collaborative work environment where you can see the direct impact of your performance and thrive both personally and professionally, then Ookla is the place for you.

Ziff Davis is an Equal Opportunity Employer. At Ziff Davis, Diversity, Equity, and Inclusion (DEI) has always been about fairness, equal opportunity, and belonging. DEI enables us to attract and retain the best talent, regardless of background or circumstances, while enabling our thousands of employees worldwide to thrive.

Compensation Range: Ziff Davis provides a range for the base pay. Factors that may be used to determine your actual pay may include your specific job related knowledge, skills, experience, and geographic location. The salary compensation for this role is £50,000 to £80,000. Individual pay within the compensation range for this business unit specific role is determined based on a variety of factors including experience, scope of the role, capabilities to perform the role, education and training, as well as business and company performance.