Reddit is a community of communities, known for open and authentic conversations on the internet. They are seeking a Senior Software Engineer to join the Site Defense team, which is responsible for protecting Reddit from various internet threats through high-scale, low-latency systems and collaboration with security teams.
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 closely within Infrastructure and with Security, and internal Safety teams to balance security, performance, and user experience
- Mentor junior engineers in their professional growth
- Contribute to the team’s ML-at-Ingress initiatives, including experimenting 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:
- 5+ 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)
- Prior experience with cloud infrastructure systems (Kubernetes, AWS / GCE ecosystems)
- Familiarity with ML systems in production, especially real-time inference or feature pipelines
- Knowledge of traffic analysis, anomaly detection, or large-scale telemetry systems