Test Engineer Jobs in Zagreb.
All active Test Engineer roles based in Zagreb.
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About Zscaler
Zscaler accelerates digital transformation to ensure our customers can be more agile, efficient, resilient, and secure. As an AI-forward enterprise, we are constantly pushing the envelope, leveraging the world’s largest security data lake to power our cloud-native Zero Trust Exchange platform. This innovation protects our customers from cyberattacks and data loss by securely connecting users, devices, and applications in any location.
Here, impact in your role matters more than title and trust is built on results. We say, impact over activity. We seek innovators who actively use AI to amplify their impact and who thrive in an environment where we leverage intelligent systems to stay ahead of evolving threats. We believe in transparency and value constructive, honest debate—we’re focused on getting to the best ideas, faster. We build high-performing teams that can make an impact quickly and with high quality. To do this, we are building a culture of execution centered on customer obsession, collaboration, ownership, and accountability.
We value high-impact, high-accountability with a sense of urgency where you’re enabled to do your best work and embrace your potential. If you’re driven by purpose, thrive on solving complex challenges, and want to be part of the team that’s helping to secure the AI age, we invite you to bring your talents to Zscaler and help shape the future of cybersecurity.
Role
We are looking for an AI Operations Engineer to join our team. This is a hybrid role based in our Zagreb office, reporting to Dominik Jurincic within the Red Teaming department. As an AI Operations Engineer, you will support the AI Red Team by operating and scaling the evaluation infrastructure that powers SPLX’s model benchmarks and MCP server registry. You’ll be the engineering force behind our continuous AI security testing workflows, ensuring our evaluation pipelines run reliably across a rapidly expanding ecosystem of LLMs and agentic tools.
What you’ll do (Role Expectations)
- Operate and extend our LLM benchmarking pipeline by integrating new models — whether through provider APIs or self-hosted deployments on virtualized infrastructure — and executing our security suite to populate and maintain the model benchmarks page
- Kick-off and maintain the SPLX MCP server registry by onboarding open-source MCP servers, provisioning their runtime dependencies, and running our dynamic code scanning and security testing against them
- Build and maintain reproducible deployment environments for evaluating third-party AI systems, ensuring consistent and reliable test conditions across diverse model and tooling configurations
- Partner with Red Team engineers and researchers to streamline evaluation workflows, automate recurring testing operations, and surface insights from benchmark and registry data
- Continuously improve the team’s internal tooling and operational processes, identifying opportunities to reduce manual effort and accelerate the cadence of model and MCP evaluations
Who You Are (Success Profile)
- You thrive in ambiguity. You're comfortable building the path as you walk it. You thrive in a dynamic environment, seeing ambiguity not as a hindrance, but as the raw material to build something meaningful.
- You act like an owner. Your passion for the mission fuels your bias for action. You operate with integrity because you genuinely care about the outcome. You adapt to what’s needed, navigating seamlessly between high-level strategy and hands-on execution.
- You are a high-trust collaborator. You are ambitious for the team, not just yourself. You embrace our challenge culture by giving and receiving ongoing feedback—knowing that candor delivered with clarity and respect is the truest form of teamwork and the fastest way to earn trust.
- You are a learner. You have a true growth mindset and never stop developing yourself, actively seeking feedback to become a better partner and a stronger teammate. You love what you do and you do it with purpose.
- You operate with urgency. You understand that in a high-growth environment, speed and quality are not mutually exclusive. You have a relentless focus on execution and a bias for action, delivering high-impact results quickly to win for the customer and the team.
What We’re Looking for (Minimum Qualifications)
- 1+ years of professional software engineering experience with Python, including the ability to ship reliable, production-quality code in a collaborative environment
- Working familiarity with the modern AI/ML ecosystem, including LLM provider APIs, model deployment patterns, and emerging protocols such as the Model Context Protocol (MCP)
- Hands-on experience with containerization (Docker) and deploying applications across cloud or virtualized infrastructure
- Solid working knowledge of REST APIs and modern integration patterns, including authentication, service orchestration, and debugging across distributed components
- Strong attention to detail and a track record of operating consistently in environments where reproducibility, rigor, and follow-through matter
What Will Make You Stand Out (Preferred Qualifications)
- Prior exposure to LLM evaluation, AI security, or red teaming workflows in a research or applied setting
- Familiarity with the broader open-source AI tooling landscape — including MCP servers, model serving frameworks, or agentic systems — and the curiosity to keep up with a fast-moving space
- Background in DevOps, platform engineering, or infrastructure automation, with comfort building reproducible test environments at scale
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At Zscaler, we are committed to building a team that reflects the communities we serve and the customers we work with. We foster an inclusive environment that values all backgrounds and perspectives, emphasizing collaboration and belonging. Join us in our mission to make doing business seamless and secure.
Our Benefits program is one of the most important ways we support our employees. Zscaler proudly offers comprehensive and inclusive benefits to meet the diverse needs of our employees and their families throughout their life stages, including:
- Various health plans
- Time off plans for vacation and sick time
- Parental leave options
- Retirement options
- Education reimbursement
- In-office perks, and more!
Learn more about Zscaler’s Future of Work strategy, hybrid working model, and benefits here.
By applying for this role, you adhere to applicable laws, regulations, and Zscaler policies, including those related to security and privacy standards and guidelines.
Zscaler is committed to providing equal employment opportunities to all individuals. We strive to create a workplace where employees are treated with respect and have the chance to succeed. All qualified applicants will be considered for employment without regard to race, color, religion, sex (including pregnancy or related medical conditions), age, national origin, sexual orientation, gender identity or expression, genetic information, disability status, protected veteran status, or any other characteristic protected by federal, state, or local laws. See more information by clicking on the Know Your Rights: Workplace Discrimination is Illegal link.
Pay Transparency
Zscaler complies with all applicable federal, state, and local pay transparency rules.
Zscaler is committed to providing reasonable support (called accommodations or adjustments) in our recruiting processes for candidates who are differently abled, have long term conditions, mental health conditions or sincerely held religious beliefs, or who are neurodivergent or require pregnancy-related support.
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