Roman Volosatovs

GitHub: @rvolosatovs • LinkedIn: @rvolosatovs

Summary

Rust, Go, Nix, Wasm and Linux expert with 10 years of professional experience specializing in low-level systems programming, networking, distributed systems and high-performance computing.

Professional Experience

2023-2026

Cosmonic: Principal Software Engineer

Tech: Rust, Go, C, Nix, WebAssembly, TCP/IP, UDP, QUIC, HTTP, gRPC, NATS.io, Kubernetes, Elixir, OpenAPI, AWS, GitHub

At Cosmonic I serve as the WebAssembly runtime expert, focusing on performance-critical low-level systems programming as part of the Bytecode Alliance.

Primarily, I build and maintain open-source tooling and low-level libraries around WebAssembly in Rust. For example, I have designed and implemented:

• bytecodealliance/wrpc - transport-agnostic, high-performance general-purpose RPC framework leveraging WebAssembly Interface Types. Presented at WasmCon 2024
• rvolosatovs/wasmlet - high-performance, multi-tenant, embeddable WebAssembly runtime optimized for cloud-native applications with focus on low-latency execution, security and deployment density
• wasmcloud/cabish - Wasm canonical ABI implementation for native code, enabling interoperability between WebAssembly and native applications
• wasmcloud/wadge - component testing and plugin framework for Wasm
• bytecodealliance/wit-deps - package manager adopted across Bytecode Alliance projects

I have migrated the core product of Cosmonic - wasmcloud/wasmcloud, a distributed WebAssembly execution platform from Elixir to Rust for improved performance and maintainability.

I am a maintainer of bytecodealliance/wasmtime - the industry-leading WebAssembly runtime.

I have completed a 250000 USD contract for NEAR blockchain in 6 months, achieving 14x performance improvement in their WebAssembly runtime:

• Conducted extensive performance profiling, bottleneck analysis, and hot path optimization
• Optimized gas instrumentation overhead via WebAssembly binary analysis and patching
• Introduced WebAssembly component model support

I actively represent Cosmonic at:

• w3c WebAssembly and WASI working group meetings
• WASI, component model and Wasmtime development meetings
• Conferences, such as KubeCon, WasmCon and Wasm I/O

2021-2023

Profian: Principal Software Engineer / Network Service Tech Lead

Tech: Rust, C, Nix/NixOS, WebAssembly, TCP/IP, HTTP, TLS, cryptography, Linux, systemd, Trusted Execution Environments (Intel SGX, AMD SEV-SNP), AWS, Equinix, OCI (docker, podman), GitHub, GitLab, Nginx, OpenID Connect, REST, OpenAPI

At Profian I worked on Enarx - open-source confidential computing platform for secure execution of WebAssembly workloads in trusted execution environments and services around it.

The company was closed due to lack of funding.

• Contributed significantly to design of the overall system
• Led a team in development of network services on a tight schedule in accordance to business objectives
• Helped team members to overcome obstacles, blockers and meet deadlines
• Mentored the team in Rust, Nix, networking and system design
• Mentored students as part of internship programs
• Represented the company at KubeCon 2022, Open Source Summit Europe 2022, FOSDEM 2023
• Represented the company at WASI SIG Registries working group meetings
• Designed and implemented:
  • Sallyport - high-performance syscall proxying library with minimal overhead, enabling secure communication between trusted execution environments and host OS
  • Networking and virtual filesystem support for Enarx execution layer
  • Drawbridge - a Merkle tree-based object registry
  • Tooling to increase developer productivity:
    • Minimal WASI shell to facilitate development and testing of virtual file systems
    • GitHub worklow job name generator
• Set up, maintained and continuously improved organization-wide CI processes and release pipelines
  • Designed and implemented a Nix-based build library for maintenance and CI performance
  • Provided Enarx image media (AMIs, ISOs, etc.)
• Brought up all initial server infrastructure using NixOS on AWS and Equinix
• Contributed to various open-source projects, most notably:
  • rust-lang/cargo
  • bytecodealliance/wasmtime

2021

Docker Inc: Senior Software Engineer (Programmable OS team)

Tech: Go, C#, Swift, Linux, Windows, MacOS, OCI (docker), GitHub, Jira, REST, OpenAPI

At Docker I worked on open-source Docker Engine and proprietary Docker Desktop application for Windows and Mac with focus on performance optimizations.

• Designed and implemented Linux cgroup-based start/stop feature released in Docker Desktop shortly after I left the company
• Contributed to moby/moby

2016-2021

The Things Industries / The Things Network: Backend Engineer

Tech: Go, C, Lua, Python, JavaScript, TCP/IP, UDP, DNS, gRPC, protocol buffers, TLS, Linux, cryptography, LoRaWAN, InfluxDB, Redis 6, OCI (docker), AWS, Azure, GitHub, GitLab, Travis CI, Nginx, IoT, edge devices, REST

At The Things Industries / The Things Network I worked on open-source and proprietary parts of a distributed, global LoRaWAN IoT network operator stack.

• Was involved directly in technical conversations with customers
• Provided technical support to high-profile customers
• Managed and represented the company at The Things Conference organized yearly
• Designed the LoRaWAN specification as part of LoRa Alliance Technical Commitee
• Provided AWS-based SaaS offerings
• Implemented support for device roaming in collaboration with other LoRaWAN network operators
• Designed and implemented:
  • LoRaWAN specification-compliant, highly-available, distributed, high-performance microservice components for multi-tenant environments:
    • Network Server - low-level packet routing and MAC layer protocol implementation
    • Join Server - performing secure device provisioning with cryptographic key derivation, exchange and HSM-backed storage
  • NOC - a proprietary component monitoring the state of the network handling several thousand requests per second
  • Build tooling:
    • Generic all-inclusive protoc OCI image, which I eventually inherited
  • Tooling to increase developer productivity:
    • protoc plugin with fieldmask support
    • Binary LoRaWAN frame decoder

2016

Eindhoven University of Technology: Software Engineer

Tech: Go, JavaScript, HTML, CSS, InfluxDB, OCI (docker), systemd, REST

• Designed, implemented and maintained a full-stack research application interfacing with Philips Hue lights used on-site in a hospital

2016

Google Summer of Code: Intern

Tech: Go, C, TypeScript, systemd

• Designed and implemented systemgo - init system in Go compatible with systemd unit file format for a browser-based operating system

Hobby Experience

• Nix and NixOS - I use Nix and NixOS on my personal machines/servers since 2016
  • Member of NixOS organization on Github
  • Contribute to NixOS/nixpkgs
  • FOSDEM 2023 talk about adopting Nix at Profian
• rund - A gRPC service in Go, which runs arbitrary Linux processes in a separate cgroup2 in an Alpine Linux container via pivot_root with mTLS authentication
• Offline speech-to-text tool using Deepspeech
• Rust bindings to a C VAD library
• Idiomatic Rust wrapper for the above
• Rust bindings to WebExtensions JS API via Wasm
• Idiomatic Rust wrapper for the above
• Julia - I use Julia for computations and occasional scripting, data analysis
• I use Linux and BSD derivatives on my machines exclusively since 2012

Education

2015-2018

BSc, Software Science; Eindhoven University of Technology

• mooshy - developed kernel-level exploit framework leveraging ShellShock and Dirty CoW vulnerabilities, demonstrating deep understanding of Linux kernel internals, and system-level security mechanisms
• Taken Declarative Programming course in university, which was completely based on Haskell with a big focus on category theory
  • Wrote a Lisp interpreter in Haskell with a study partner as part of the course

About me

• Languages:
  • Russian - bilingual
  • Latvian - bilingual
  • English - proficient
  • French - basic knowledge
  • Dutch - basic knowledge
• Studied in a Jazz college part-time in parallel to high school studies
• Worked as a professional guitarist, guitar teacher and math teacher in the past
• I like various types of art, board games, powerlifting, hiking, snowboarding and nature