Staff Software Engineer | Systems and L7 Protocols

About Formal

Formal is building a network security platform for the AI era. As agents gain access to sensitive data and production systems, organizations need control over the actions they take and the data they receive. We enforce those controls directly in the network path, with a shared policy layer for humans and agents across databases, infrastructure, APIs, and AI tools.

We are trusted by leading companies such as Cursor, Decagon, Notion

, and more to solve problems across data security and compliance, data quality management, and infrastructure access.

Formal is backed by top-tiers VCs including Thrive Capital and Y Combinator with angel investors that include executives and founders from Datadog, Clickhouse, Plaid, and Vanta.

About the Role

Build the protocol-aware proxies at the core of Formal. You'll work on how connections are established, how application-layer protocols are parsed, and how requests and responses flow between clients and upstream systems.

The work goes beyond conventional web backends: understanding wire protocols, managing connection and session state, and working with existing clients without breaking their behavior or adding unnecessary latency. You'll also build the distributed backend that coordinates these proxies, owning projects from research and implementation through debugging and scaling in production.

Our stack includes Go, Rust, Temporal, and AWS, with protocol integrations spanning PostgreSQL, MySQL, Kafka, S3, SSH, HTTP, gRPC, and MCP.

What You'll Do

• Build application-layer proxies for databases, infrastructure, and AI tools, working directly with protocols such as PostgreSQL, MySQL, SSH, HTTP, and MCP.
• Implement how Formal parses and modifies protocol messages, handles authentication handshakes, and manages connections and streaming responses.
• Extend protocol support to work with more clients, drivers, and upstream systems, preserving their expected behavior through the proxy.
• Build the distributed services that configure and coordinate proxies, synchronize state, and process the events they produce.
• Solve production problems across the traffic path, improving throughput, latency, memory usage, and connection reliability.

What You Need

Experience building systems software, proxies, database internals, networking software, or distributed services.

Experience with Go, Rust, or another language used for systems programming.

Strong networking fundamentals, including TCP, TLS, connection management, and application-layer protocols.

Experience building concurrent software and reasoning about resource usage, timeouts, and partial failures.

Experience debugging production systems using logs, traces, profiling, or packet captures.

A preference for simple, maintainable code and ownership from design through production.

Nice-to-Haves

Experience implementing or extending protocols such as PostgreSQL, MySQL, Kafka, SSH, HTTP, or gRPC.

Experience with SQL parsing and programming language compiler work

Experience with protocol parsers, connection multiplexing, authentication handshakes, or TLS termination.

Experience with authorization systems, security infrastructure, or traffic inspection.

Experience with Temporal, Kubernetes, Terraform, or operating software in customer environments.