Sergey Linnik

Sergey Linnik

Engineering Manager

linniksa@gmail.com GitHub Telegram

About

Engineering Manager with 16+ years of experience designing high-load systems for e-commerce, logistics, payments, and data platforms. Track record of launching B2B and SaaS products, leading cross-functional teams, and establishing development processes.

Skills

Programming Languages

Go PHP TypeScript Python C C++

Databases

PostgreSQL ClickHouse MongoDB

Infrastructure & Tools

Kafka Docker RabbitMQ Trino

Management

Team Leadership Cross-functional Teams Process Design

Experience

Development Group Lead

Magnit OMNI

Marketplace logistics management team at mm.ru

Team: 4 Backend Frontend 2 QA

FBS model — seller APIs for order management, delivery time calculation. Coordinating across domains: distribution centers, pickup points, WMS.

FBS Launch

  • Designed and launched marketplace seller APIs
  • Built a real-time delivery time calculation engine
  • Decomposed monolith into independent services

Logistics Platform

  • Route calculation and delivery SLA enforcement
  • Domain coordination: distribution centers, pickup points, WMS
  • End-to-end shipment tracking from warehouse to recipient

Noteworthy

  • › Launched FBS model in 4 months with a minimal team, while decomposing a distributed monolith in parallel
  • › Wrote a Kafka UI plugin — displays encoded proto messages from internal spec-storage (not Schema Registry)

Development Group Lead

VK Cloud

Cloud analytics — data collection and delivery to DWH.

Team: Backend

Essentially a staff engineer role. Rewrote the data delivery pipeline to DWH with reliability guarantees and metrics. Simplified the pipeline by removing redundant points. Integrated Trino for analytical queries, implemented CDC for real-time data synchronization.

Analytics Platform

  • Accelerated customer billing reports by 10x+
  • Integrated Trino for analytical queries
  • Implemented CDC (Change Data Capture) for real-time data synchronization
Go Python Kafka ClickHouse PostgreSQL YTSaurus Trino

Noteworthy

  • › Built a real-time Tarantool → PostgreSQL replicator

Senior Developer

Yandex

Shared data storage.

Joined as a Go developer with growth prospects toward a lead role, ended up writing a mix of C++ and custom Cython.

Python C++ Cython Go

Unit Lead

X5 Group

PIM for marketplace. Legacy PHP monolith.

Team: Teamlead 3 Fullstack SA QA

Marketplace project based on Perekrestok online and vprok.ru. Built a PIM development team from scratch in 4 months.

Marketplace PIM

  • Product information management system, 200k+ SKU
  • Migration and evolution of legacy PHP monolith
Go PHP PostgreSQL MongoDB RabbitMQ Kafka

Noteworthy

  • › Built a real-time image conversion service — saved 2 servers (16 cores each), improved quality and reduced size

Development Group Lead

RetailDriver

B2B SaaS CRM + boxed versions with enterprise deployments (Restore, Tvoy Dom, Lacoste).

Team: 3 Backend 2 Frontend Mobile

Grew from senior developer to team lead. Created many internal product solutions — audit trail, trigger language improvements. Introduced SSO, GitLab, deployment via Docker images, etc.

B2B SaaS CRM

  • SaaS + boxed versions with enterprise deployments
  • Expression language for trigger system (low-code automation)
  • SPA transition (Vue.js), explicit front/back separation
PHP Go C Symfony PostgreSQL Docker

Noteworthy

  • › Built an internal tunneling service from the internet to localhost using only a standard SSH client
  • › Wrote an hstore-extension for faster PHP hstore decoding (available on GitHub)
  • › Reduced test time from 12 hours to 15 minutes — 90 parallel threads on spot instances

Senior PHP Developer → Team Lead

Neoline

Backends for web and mobile apps, video traffic distribution, IVR.

Led a team of up to 10 developers. Backends for web and mobile apps, video traffic distribution, IVR development.

Mobile Backends

  • Built backends for iOS/Android apps
  • Video traffic distribution
  • Automated deployments with Jenkins and Capistrano
PHP Jenkins Capistrano

Noteworthy

  • › Built a full-featured epub reader in C++ for Samsung Bada OS — with page-turning animations on low-cost devices

PHP Developer

allvrn.ru

Web project development and support, CI implementation.

PHP Zend Framework Symfony 2 Doctrine 2 Sphinx

Noteworthy

  • › Launched a project on Symfony 2 while the framework was still in early alpha
  • › Tuned Sphinx search: keyboard layout correction, RT indexes, improved ranking algorithms

Web Developer

D'Arts (Advertising Agency)

Website development and frontend programming.

PHP JavaScript

Education

Voronezh State Technical University

Specialist (5-year degree) — Automated Design Systems

Automation and Robotization of Machine Building

Certificates & Awards

Languages

Russian — native
English — B2 (Upper-Intermediate)