Staff Frontend Engineer

About Castle

Castle is a Series A startup on a mission to create a safer online world by protecting platforms from fraud, abuse, and malicious activity. Trusted by companies like Canva, Atlassian, and Rockstar Games, we’re backed by Y Combinator, Index Ventures, and top-tier angels from Datadog, Stripe, and New Relic. Our fast-moving team is scaling globally, helping platforms stay secure while thriving in a rapidly evolving digital landscape.

The role

We are seeking a Staff Frontend Engineer with expertise in Angular and React to join our team. This role is ideal for a product-minded engineer with excellent UI and product sense. At Castle, we foster a culture of innovation, collaboration, and ownership. If you enjoy working in a fast-paced, startup environment where you can make a real impact, you’ll thrive here.

This is a fully remote role, with teammates in the US, Poland, Portugal, Sweden, and France. We have a local presence in New York and Cracow if you prefer to come into the office. We expect candidates to be located in time zones between UTC-5 (New York) and UTC+1 (Cracow) to ensure smooth collaboration.

Responsibilities

• Take ownership of the design and development of Castle Dashboard, focusing on exceptional user experiences and design.
• Work closely with Product Designers to ensure a seamless design-to-development workflow. Structure the codebase to empower designers with autonomy in making UI changes while maintaining consistency and performance.
• Analyze dashboard usage and performance to track feature adoption and proactively optimize data-heavy visualizations for speed and efficiency.
• Leverage AI and automation tools to streamline development workflows, accelerate testing, and enhance frontend performance.
• Ship incrementally and frequently, driving a constant flow of iterative, customer- and internal-feedback-driven development.
• As part of a small team, you will have a significant impact on the direction and implementation of projects, shaping the future of our product.

Qualifications

• 6+ years of professional software development experience, with a strong focus on frontend technologies.
• Extensive experience building and maintaining complex production applications using Angular and/or React.
• Demonstrated experience in building performance-optimized web applications, ideally in a SaaS or startup environment.
• Strong product sense with the ability to understand user needs and translate them into technical solutions.
• Excellent problem-solving skills and attention to detail.
• Strong verbal and written English communication skills to collaborate effectively in a distributed team and, when necessary, support customer-facing interactions.

Benefits

• Salary: $135k - $196k
• Flexible work hours. We prioritize outcomes over hours spent.
• Unlimited PTO. Take the time you need to recharge and maintain a healthy work-life balance.
• Paid parental leave. Supporting new parents during their transition.
• We'll provide the essential computer and related equipment to ensure you have everything you need to excel in your role.