Staff Software Engineer - Site Defense

Details

Reddit's Transport and Site Defense teams build and operate foundational infrastructure behind one of the largest sites in the world. The Site Defense team protects Reddit at internet scale against DDoS attacks, automated abuse, large-scale scraping, and other network-level threats. This role sits at the intersection of distributed systems, networking, security, and applied machine learning, with responsibility for designing and owning critical infrastructure that safeguards Reddit's data from large-scale attacks.

Responsibilities

• Design, build, and operate high-scale, low-latency systems that protect Reddit from DDoS attacks, bots, and automated abuse.
• Analyze, develop, and evolve ingress-level defenses across CDN, edge, and internal infrastructure layers.
• Build systems to detect, score, and mitigate malicious traffic in real time at per-request and per-user granularity.
• Partner with Infrastructure, Security, and internal Safety teams to balance security, performance, and user experience.
• Mentor junior engineers in their professional growth.
• Contribute to ML-at-Ingress initiatives, including experiments with models for traffic classification, bot detection, and anomaly detection.
• Own services end-to-end, including design, implementation, on-call, and operational excellence.
• Participate 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, including Python, Go, Rust, Java, or C++.
• Excellent communication skills and the ability to collaborate with a service-oriented team and company.
• Experience with DDoS mitigation, WAFs, bot management, or abuse prevention systems.
• Experience with networking fundamentals, including HTTP, TLS, TCP/IP, proxies, CDNs, and load balancing.

Nice to Have

• Experience with anti-abuse frameworks and bot scores, such as ReCaptcha, Datadome, or Turnstile.
• Experience with browser fingerprinting frameworks, such as fingerprintJS or ThumbmarkJS.
• Familiarity with machine learning systems in production, especially real-time inference or feature pipelines.

Benefits

• Comprehensive healthcare benefits and income replacement programs.
• 401(k) with employer match.
• Global benefit programs supporting workspace, professional development, caregiving, and other needs.
• Family planning support.
• Gender-affirming care.
• Mental health and coaching benefits.
• Flexible vacation and paid volunteer time off.
• Generous paid parental leave.
• Equity in the form of restricted stock units.

Compensation

The base salary range is $217,000–$303,900 USD. The role may also be eligible for commission depending on the position offered. Reddit provides additional benefits to U.S.-based employees, including medical, dental, and vision insurance, a 401(k) program with employer match, vacation, and parental leave. Interview recording, transcription, and summarization by artificial intelligence may apply to select roles and locations, with an option to opt out before scheduled interviews.