Description
Reddit's Transport and Site Defense teams build and operate foundational infrastructure behind one of the largest sites in the world. We are looking for a Staff Software Engineer to join the Site Defense team within Reddit's Infrastructure organization.
Site Defense is responsible for protecting Reddit at internet scale,serving as the first line of defense against DDoS attacks, automated abuse, large-scale scraping, and other network-level threats. This is a high impact role that sits at the intersection of distributed systems, networking, security, and applied machine learning.
You will design and own the critical infrastructure that safeguards Reddit's data from large scale attacks. Responsibilities include:
- Designing, building, and operating high-scale, low-latency systems that protect Reddit from DDoS attacks, bots, and automated abuse.
- Analyzing, developing and evolving ingress-level defenses across CDN, edge, and internal infrastructure layers.
- Building systems to detect, score, and mitigate malicious traffic in real time at per-request and per-user granularity.
- Partnering closely within Infrastructure and with Security, and internal Safety teams to balance security, performance, and user experience.
- Mentoring junior engineers in their professional growth.
- Contributing to the team's ML-at-Ingress initiatives, including experimenting with models for traffic classification, bot detection, and anomaly detection.
- Owning services end-to-end, including design, implementation, on-call, and operational excellence.
- Participating in incident response and post-incident analysis for large-scale network or abuse events.
Requirements:
- 7+ years of experience building and operating high throughput and low latency production distributed systems.
- Software development experience in one or more general purpose programming languages; Python, Go, Rust, Java, C++.
- Excellent communication skills to collaborate with a service-oriented team and company.
- Experience with DDoS mitigation, WAFs, bot management, or abuse prevention systems.
- Experience with networking fundamentals (HTTP, TLS, TCP/IP, proxies, CDNs, load balancing).
Nice to have:
- Experience with anti-abuse frameworks and bot scores (ReCaptcha, Datadome, Turnstile).
- Experience with browser fingerprinting frameworks (fingerprintJS, ThumbmarkJS).
- Familiarity with ML systems in production, especially real-time inference or feature pipelines.
Benefits:
- Comprehensive Healthcare Benefits and Income Replacement Programs.
- 401k with Employer Match.
- Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support.
- Family Planning Support.
- Gender-Affirming Care.
- Mental Health & Coaching Benefits.
- Flexible Vacation & Paid Volunteer Time Off.
- Generous Paid Parental Leave.