Publication
.NET Best Practices and Tips by Toptal Developers
https://www.toptal.com/developers/dot-net/tips-and-practices
Andrei is available for hire
Hire AndreiAndrei Smirnov
Verified Expert in Engineering
Full-stack Developer
Antalya, Turkey
Toptal member since December 11, 2014
Bio
Andrei is a back-end and distributed systems engineer with vast experience in building production infrastructure and high-stakes systems at Chainlink, Microsoft, Deutsche Bank, and Obol Network. He has staff-level expertise in Go back-end development, distributed systems, APIs, fault-tolerant architectures, performance optimization, observability, and reliability engineering. Andrei also brings a strong background in C/C++ and systems programming, offering comprehensive technical leadership.
Portfolio
Obol & DV Labs
Go, Blockchain, Solidity, Ethereum Smart Contracts, PostgreSQL...
Chainlink
Go, Distributed Systems, Custom Protocols, Ethereum Smart Contracts, Blockchain...
mode.io
WebAssembly (Wasm), WebRTC, CMake, QML, JavaScript, Cryptography, Go, React, Qt...
Experience
- C++ - 20 years
- Technical Leadership - 10 years
- Software Architecture - 10 years
- Go - 8 years
- Distributed Systems - 7 years
- Blockchain - 4 years
- Ethereum - 4 years
- AI Agents - 1 year
Work Experience
Staff Protocol Engineer
2023 - 2026
Obol & DV Labs
- Led engineering across protocol development, smart contracts, back-end services, and infrastructure, providing architectural direction and cross-team technical leadership.
- Drove DVT performance improvements by instrumenting the protocol stack, identifying latency bottlenecks, and reducing end-to-end processing latency.
- Implemented HotStuff consensus alongside the existing QBFT implementation and designed a pluggable consensus architecture supporting dynamic algorithm selection while preserving required Byzantine Fault Tolerance (BFT) guarantees.
- Led protocol compatibility work with Ethereum consensus and validator clients, including Prysm, Teku, Lighthouse, Nethermind, and Vouch, to support upcoming forks and EIPs.
- Led collaboration with Nethermind on [Pluto, an alternative Rust implementation](https://blog.obol.org/announcing-pluto/) of the Obol distributed validator client, covering protocol compatibility, client architecture, and engineering coordination.
- Introduced AI-assisted engineering workflows for specification analysis, architecture, and design review, implementation, testing, and documentation, shortening engineering feedback loops and improving development consistency.
- Architected AI-assisted incident-response tooling that correlates operational context with metrics, logs, and traces to accelerate debugging, root-cause analysis, and post-incident investigation.
Technologies: Go, Blockchain, Solidity, Ethereum Smart Contracts, PostgreSQL, Decentralized Finance (DeFi), Grafana, Ethereum, Docker, Cryptography, Web3, Large Language Models (LLMs), AI-generated Code, Artificial Intelligence (AI), Software Architecture, Fintech, Back-end Development, AI Agents, Distributed Systems, Back-end, Technical Leadership, Agentic AI, Git, NoSQL, Python 3, Concurrent Programming, Google Protocol Buffer, REST, REST APIs, MacOS, APIs, Custom Protocols, Cryptocurrency, Observability, Databases
Senior Platform Engineer
2021 - 2023
Chainlink
- Designed and implemented the initial version of [Chainlink Functions](https://chain.link/functions), spanning back-end services, smart contracts, APIs, and production observability.
- Drove major improvements in platform observability through Grafana dashboards, metrics, monitoring, alerting, and production debugging workflows.
- Led external project integrations, including LayerZero, coordinating work across blockchain infrastructure, back-end systems, and platform engineering boundaries.
Technologies: Go, Distributed Systems, Custom Protocols, Ethereum Smart Contracts, Blockchain, Git, NoSQL, MySQL, Concurrent Programming, Google Protocol Buffer, REST, REST APIs, MacOS, Docker, Solidity, APIs, PostgreSQL, Cryptocurrency, Web3, Decentralized Finance (DeFi), Grafana, Software Architecture, Fintech, Back-end, Observability, Databases
Lead Software Engineer
2015 - 2021
mode.io
- Designed and developed a post-quantum, secure messaging system that included client framework, client applications, back end, and web portal management.
- Refactored legacy crypto code using the newest C++17 features, with full test coverage and a new build system with CMake and Conan.
- Designed and integrated voice and video calls with WebRTC.
- Added support to WebAssembly (Emscripten) to enable messaging applications to run in browsers.
- Mentored new team members, conducted technical webinars, and maintained detailed documentation.
Technologies: WebAssembly (Wasm), WebRTC, CMake, QML, JavaScript, Cryptography, Go, React, Qt, C++, Git, MySQL, Concurrent Programming, Google Protocol Buffer, REST, MacOS, Qt 5, C++17, SQL, PostgreSQL, Software Architecture, Distributed Systems, Back-end, Observability, DLL, Databases
Freelance Software Engineer
2015 - 2015
DreamFactory
- Designed and developed .NET SDK for DreamFactory API: https://github.com/dreamfactorysoftware/.net-sdk.
- Built production-ready SDK for the modern .NET clients.
- Addressed users' feedback and adopted best practices of building SDKs for the .NET platform.
Technologies: REST APIs, C#, .NET, Git, REST, APIs, Back-end
Technical Lead
2014 - 2015
Return On Intelligence
- Designed and developed a web portal for employee benefits management (insurance, retirement, and more).
- Introduced a web services mocking approach to ease local debugging and troubleshooting.
- Enabled automatic testing using Selenium. Implemented and enforced product quality tools.
- Improved corporate build and deployment strategy dramatically to minimize day-to-day efforts.
Technologies: C#, Back-end Development, Git, Google Protocol Buffer, REST, Software Architecture, Back-end, Databases
Lead Application Developer
2013 - 2014
Deutsche Bank
- Designed and developed a metadata-driven framework for desktop interoperability and enabled several existing applications to use this framework. Currently, all Autobahn software uses a framework called Synapse.
- Enhanced WPF applications (FX trading) for investment banking with respect to performance, security, and code quality.
- Developed a number of WPF controls (MVVM) for banking applications.
Technologies: .NET, C#, Back-end Development, REST, REST APIs, Fintech
Senior Software Developer
2010 - 2012
Microsoft
- Developed a rapid data serialization SDK (similar to Google ProtoBuf), including the C# code generator for it: Github.com/microsoft/bond.
- Built an object-oriented logging framework (business data logging) for in-house cloud infrastructure, now used by AdCenter and Bing.
- Implemented a remote-procedure calls (RPC) engine and toolset for a brand new key-value store (NoSQL) currently used by Azure.
Technologies: C++, NoSQL, .NET, C#, Back-end Development, Git, Win32 API, Concurrent Programming, REST, CMake, Qt 5, C++17, SQL, PostgreSQL, Software Architecture, Distributed Systems, Back-end, DLL, Databases
Senior Software Engineer
2009 - 2010
EMC Corporation
- Worked on a high-availability Linux-based cluster (HA), integrating and configuring Pacemaker for network-attached storage (NAS).
- Introduced the cgroups feature usage to the HA cluster.
- Developed an out-of-memory (or overcommit) monitoring daemon in C.
Technologies: Linux, C, C++, Concurrent Programming, CMake, Qt 5, C++17, PostgreSQL, Software Architecture, Distributed Systems
Senior Software Engineer
2006 - 2009
Motorola, Inc.
- Worked on several Motorola mobile device platforms, implementing security features (JSR177), branding services (T-Mobile MyFaves), etc.
- Integrated Adobe Flash Lite player to the mainstream Motorola mobile platform (P2K). Collaborated with Adobe.
- Participated in AJAR mobile platform development and integration into Motorola's mobile devices.
- Developed a number of internal tools for embedded software development in C# and C++.
Technologies: C++, Embedded Systems, C, C++17, DLL
Senior Software Engineer
2002 - 2005
The Institute of Telecommunications
- Designed and developed a 3D engine for GIS (Geographical Information Services) in C++, STL, and OpenGL.
- Developed a cross-platform computational geometry math library in C++.
- Designed and built a full-featured application suite for manipulating GIS data.
- Programmed a large-image processing engine (satellite imagery) in C and C++.
Technologies: Qt, OpenGL, 3D Graphics, C++, C, C++17, DLL
Project History
DB Autobahn
https://autobahn.db.comParticipated in Autobahn FX products development: from protocols to user interface (.NET/WPF).
I designed and implemented a flexible interoperability protocol that connected many Autobahn products (existing and new). This system is called Synpase and is currently in production and driving the Autobahn ecosystem.
I designed and implemented a flexible interoperability protocol that connected many Autobahn products (existing and new). This system is called Synpase and is currently in production and driving the Autobahn ecosystem.
Vault
https://github.com/pinebit/vaultA tiny C++ library that manages password-protected files, with a very simple API to use.
Imagine you needed to persist some user-sensitive information in a password-protected file—this little library addresses this need.
Imagine you needed to persist some user-sensitive information in a password-protected file—this little library addresses this need.
React-CR
https://github.com/pinebit/react-crA tiny library for conditional rendering in JSX. The idea here was to express conditions declaratively (JSX style) rather than inject conditional JavaScript code. The library is used in some real projects in production.
The Largest App
https://github.com/pinebit/largestappA desktop application for finding the largest files and folders on your computer. The idea was to build a primer app using Qt5/QML. To make it more useful, I made it search for large files on the computer.
Stack: C++ and Qt5 with QML UI.
Stack: C++ and Qt5 with QML UI.
Balabol AI Translator App
https://balabol.appA simple deep-coding exercise with Claude: a translator app for expats that leverages five different AI models for text translation, text-to-speech, and speech-to-text. This is a PWA that can be easily added to your mobile home screen without installation.
Monoko
https://github.com/pinebit/monokoMonoko is a fast, native image viewer for macOS, built for Apple Silicon. This is a deep-coding exercise. The goal was to build the most power-efficient, GPU-optimized image viewer for macOS. It's possibly the fastest image viewer in the world right now.
zxradio.org
https://zxradio.org/ZX RADIO is a browser player for curated ZX Spectrum AY-3-8912 chip music, rendered live through WebAssembly and AudioWorklet. My dedication to ZX Spectrum history (50th anniversary). The music is rendered in the browser in real time.
Charon DVT
https://github.com/ObolNetwork/charonCharon is the distributed validator client (pronounced 'kharon'), an HTTP middleware client for Ethereum Staking that enables you to safely run a single validator across a group of independent nodes. It is used by stakers to distribute the responsibility for running Ethereum Validators across multiple instances and client implementations.
Chainlink Functions
https://docs.chain.link/chainlink-functionsChainlink Functions provides your smart contracts access to trust-minimized compute infrastructure, allowing you to fetch data from APIs and perform custom computation. Your smart contract sends source code in a request to a Decentralized Oracle Network (DON), and each node in the DON executes the code in a serverless environment. The DON then aggregates all the independent return values from each execution and sends the final result back to your smart contract.
Publication
.NET Best Practices and Tips by Toptal Developers
https://www.toptal.com/developers/dot-net/tips-and-practices
Publication
The Missing Article About Qt Multithreading in C++
https://www.toptal.com/developers/qt/qt-multithreading-c-plus-plus
Publication
A Vital Guide to Qmake
https://www.toptal.com/developers/qt/vital-guide-qmake
Publication
How to Boot-strap and Create .NET Projects
https://www.toptal.com/developers/dot-net/bootstrap-and-create-dot-net-projects
Publication
Meet Bond, Microsoft Bond - A New Data Serialization Framework
https://www.toptal.com/developers/microsoft/meet-bond-microsoft-bond
Education
1996 - 2002
Specialist Degree in Engineering
Baltic State Technical University - Saint-Petersburg, Russia
Certifications
APRIL 2026 - PRESENT
Claude with Anthropic API
SkillJar
Skills
Libraries/APIs
API Development, React, OpenGL, Win32 API, WebRTC, Node.js, REST APIs
Tools
Git, Grafana, Claude Code, Codex, CMake, ComfyUI, Terraform
Languages
C, Go, QML, C++, C#, C++17, JavaScript, Python 3, SQL, TypeScript, Solidity, Objective-C
Frameworks
.NET, Qt, Google Protocol Buffer, Qt 5, Next.js, Metal
Paradigms
Concurrent Programming, REST
Platforms
Ethereum, Windows, Blockchain, Linux, Docker, Apache Kafka, Kubernetes, MacOS
Storage
Databases, NoSQL, PostgreSQL, MySQL
Other
Cryptography, APIs, Custom Protocols, Cryptocurrency, Web3, AI-generated Code, Artificial Intelligence (AI), Software Architecture, Back-end Development, AI Agents, Distributed Systems, Back-end, Technical Leadership, Agentic AI, Observability, DLL, Agentic Coding, AI Engineering, WebSockets, CI/CD Pipelines, 3D Graphics, Ethereum Smart Contracts, Decentralized Finance (DeFi), Large Language Models (LLMs), Temporal, AI Security, Argo CD, WebAssembly (Wasm), Embedded Systems, Fintech, AI Assistants
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