Senior Software Engineer – Virtual Network Security Appliance (C++ / Go / Rust)

Hybrid – Pune, India · Full-time, direct hire · Rust · C/C++ · Go · Linux networking · Containers · AWS

The role

You'll build and own Securly's edge proxy appliance: a virtual appliance (containers on a minimal Linux OS image) that we deliver into customers' school networks to intercept, inspect, and filter web traffic. You own it end to end: the traffic-handling datapath, how it's packaged and shipped, how it updates itself safely, how it fails without cutting off a network, and how the deployed fleet reports back to our AWS control plane.

This is a senior role in Pune Engineering, reporting to the SVP of Engineering.

You'll bring

You've shipped software that runs inside a customer's network, such as a proxy, firewall, secure web gateway, VPN gateway, load balancer, or network security appliance. We're open to strong C/C++ or Go engineers whose Rust is still growing, as well as Rust engineers with appliance or proxy experience.

8+ years of software engineering in systems, networking, or security products
Production experience in Rust, C/C++, or Go. Rust is where the new proxy is headed, so you'll write Rust here.
Network programming below the HTTP layer: TCP streams, sockets, bidirectional forwarding, transparent proxying (TPROXY), TLS, and the Linux network stack
A shipped appliance, proxy, or network security product you can name, and the problems you solved on it
Containerization and software delivery into customer networks: Docker image builds, minimal Linux images, container networking, installs and upgrades
Network security fundamentals: TLS, mTLS, certificates, and hardening systems against tampering
Performance testing and profiling: load tests, CPU/memory profiling, flame graphs
Working knowledge of AWS and infrastructure as code (CloudFormation or Terraform)

Strongly preferred: production Rust (async, Tokio); Linux kernel networking (eBPF/XDP, netfilter, routing); HAProxy or Envoy; OTA or fleet management at scale; high-availability design (watchdogs, VRRP/CARP failover).

Nice to have: RADIUS; fleet messaging (gRPC over mTLS, MQTT, AWS IoT Core); observability (CloudWatch, Splunk, SLO definitions); immutable OS images (Flatcar, Talos, Buildroot).

What you'll build

Proxy datapath: TCP interception, transparent proxying, and TLS inspection, plus Linux network stack tuning for throughput and latency.
Appliance packaging and delivery: Container images and a minimal, immutable OS image that installs and runs cleanly inside customer networks.
Safe updates: Zero-downtime OTA updates with A/B swaps, automatic health-check rollbacks, and phased canary rollouts to machines you can't log into.
Fail-open and high availability: Watchdogs, failover, and bypass logic so the customer's internet keeps working if the appliance doesn't.
Fleet control plane: Secure, low-latency channels for policy updates and telemetry between deployed appliances and AWS.
Security hardening: Protecting the appliance against tampering and configuration drift in environments we don't own.
Performance baselines: Load tests that simulate sharp, predictable traffic spikes (everyone on the network coming online at the start of the school day), profiling, and written baselines.

The technical challenges

Traffic you have to handle correctly, every time. The proxy sits in the path of all web traffic on the network. Latency, memory use, and correctness under load all matter.
Machines you can't touch. Appliances run inside networks we don't control. Updates, rollbacks, and debugging all have to work remotely, through telemetry and careful rollout design.
Failure has to be safe. If the appliance crashes or an update goes wrong, traffic must keep flowing. Designing fail-open behavior and failover is core to the job.
Every environment is different. Customer networks vary widely in hardware, firewall setups, and configuration. The appliance has to install and run cleanly across all of them.
Architecture decisions are yours. Many design choices, standards, and documents for the appliance are still to be defined. You'll make those decisions and write them down.