Staff Software Engineer — Networking & DNS Infrastructure

We're BlueCat—a Great Place to Work for good reason. Our team solves critical network challenges for some of the world's largest organizations. In simple terms, we manage the systems that keep networks running smoothly, securely, and reliably—the backbone infrastructure that powers digital transformation for enterprises globally. Our Intelligent Network Operations platform delivers and enables AI-driven agentic ops at scale, automating and simplifying how companies manage, secure, and optimize their networks.

But what makes us different is how we work: we believe great work happens in an environment where you're trusted, heard, and supported. With teams globally, we're building a workplace culture that values collaboration and integrity as much as innovation. If you're looking to advance your career with a company that invests in its people, this is it.

About the role:

We're looking for a systems engineer to build and operate high-throughput, low-latency network infrastructure written in Rust. You'll work on the core data plane of a production DNS platform. This service that handles large query volumes with tight latency budgets, strong reliability guarantees. It's also a role where you stay close to the people who use what you build, translating real customer problems into the right technical solution.

What you'll do:

• Design and implement components of a high-performance DNS engine: resolvers, forwarders, caching layers, and request-processing pipelines.
• Implement and harden DNS protocol features across transports: UDP/TCP, DNS-over-HTTPS, DNS-over-TLS, DNSSEC, EDNS Client Subnet, and related standards.
• Build features for traffic management and reliability: global server load balancing, health-checking, policy evaluation, response rewriting, and threat/security filtering.
• Profile and optimize hot paths: memory allocation, data structures (tries, caches), connection pooling and multiplexing and back changes with benchmarks.
• Integrate the data plane with control-plane services: configuration updates across distributed deployed nodes.
• Own observability for your components: metrics, structured logging/tracing, and diagnostics that make production behavior legible.
• Write thorough unit, integration, and component tests; keep the build green and the codebase clean (linting, formatting, dependency hygiene, security advisories).

Working with customers and product
• Listen directly to customers: through support escalations, field reports, and conversations to understand the problem behind the request, not just the feature they asked for.
• Partner with product management to turn customer pain points into well-scoped features, and help shape the roadmap by grounding it in what's technically feasible and where the real leverage is.
• Reproduce and diagnose customer-reported issues in production traffic patterns, then design fixes that address the root cause rather than the symptom.

What we're looking for:

• Strong systems programming experience in Rust, including async programming with tokio
• Solid grasp of networking fundamentals: TCP/UDP, TLS, HTTP, and ideally DNS or another wire protocol.
• Experience writing performance-sensitive concurrent code, and the instinct to measure before and after with benchmarks and profiling.
• A test-first, correctness-oriented mindset — you care about edge cases, graceful shutdown, backpressure, and deterministic behavior under concurrency.
• Comfort working across a large workspace: crates/modules, shared libraries, plugin boundaries, and CI.
• Strong communication skills and genuine customer empathy: you can talk to non-engineers, ask the right questions, and translate fuzzy problems into concrete engineering work.

Nice to have:

• Open source work in the Rust/tokio ecosystem a major plus
• DNS internals (record types, SOA/TTL handling, DNSSEC, ECS, dnstap).
• Prometheus metrics, tracing, and production observability practices.
• Protobuf/gRPC, service discovery, and control-plane/data-plane architectures.
• Allocator tuning (jemalloc/mimalloc), lock-free/atomic programming, and low-level performance work.
• Experience upgrading language toolchains and managing dependency/security posture over time.
• Experience working directly with customers or in a product-partnered engineering role.

Impact:

Your work directly affects the performance, resilience, and security of a service that sits on the critical path for every request that depends on it. Small improvements in latency, memory, or correctness matter at scale, and because you stay close to customers, you'll see those improvements land as real problems solved.