JulianRassolov
R&D Director & Engineering Leader
Engineering leader and systems architect with 15+ years designing platforms at scale and building the organizations that run them.
Distributed Systems Architecture
Designing fault-tolerant, high-throughput systems built for real-world traffic and scale.
Engineering Organisation Design
Scaling engineering teams from zero — hiring, structuring, and building culture for sustained delivery.
AdTech & RTB Platforms
End-to-end real-time bidding infrastructure and high-throughput programmatic advertising platforms.
Technical Strategy & Roadmapping
Aligning architecture decisions and engineering investment with business objectives and growth timelines.
Engineering at the Intersection of Architecture and Leadership
I'm an R&D Director and engineering leader with 15+ years of experience designing and delivering high-performance systems that handle real-world scale. My career has been shaped by a commitment to engineering excellence — from architecting distributed platforms to building the organizations that sustain them.
I've led engineering teams across AdTech, media, and platform companies, scaling organizations from scratch into high-output, autonomous delivery machines. I care deeply about technical quality, team growth, and the alignment between engineering decisions and business outcomes.
Based in Oak Bluff, Manitoba, Canada, and fluent in four languages — I bring both the technical depth and the organizational perspective needed to lead at scale.
Languages
High-Performance Systems
Real-time distributed architectures handling millions of requests per second
AdTech & RTB Platforms
Deep expertise in real-time bidding, programmatic advertising, and high-throughput auction infrastructure
Engineering Leadership
Built and mentored 4 engineering teams from 0 to 18+ high-performing engineers
Multilingual
English · Russian (Native) · Hebrew · Ukrainian — effective across global teams
Work History
15+ years building systems at scale — from individual contributor to engineering leader.
R&D Director
Leading R&D across multiple engineering teams, driving architecture and technology strategy for high-performance platform products. Accountable for roadmap, hiring, and technical execution.
- Achieved 72% reduction in end-to-end bidding pipeline latency through infrastructure redesign and algorithmic optimizations
- Scaled engineering organization from 0 to 4 teams (~18 engineers) through structured hiring and mentorship programs
- Defined and executed multi-quarter technical roadmaps aligned with business goals
- Established engineering culture centered on performance, code quality, and continuous delivery
Engineering Lead — AdTech Platform
Led a cross-functional engineering team building a real-time bidding platform processing billions of bid requests daily. Owned technical decisions from architecture through production.
- Designed and built a high-throughput RTB engine supporting 500K+ QPS at sub-10ms latency
- Integrated multiple demand partners and header bidding workflows, improving auction fill rates and yield
- Reduced infrastructure costs by 35% through service decomposition and right-sizing initiatives
- Grew and mentored a team of 8 backend engineers from junior to senior level
Senior Backend Engineer
Core engineer on distributed systems serving large-scale media and advertising workflows. Focus on performance optimization and reliability.
- Rebuilt core data ingestion pipeline, improving throughput by 4× and eliminating data loss under load
- Implemented distributed tracing and observability stack across 20+ microservices
- Led migration from monolith to service-oriented architecture with zero downtime
Backend Engineer
Built backend services and APIs for media-tech products. Developed expertise in high-traffic systems, database optimization, and cloud infrastructure.
- Developed RESTful APIs consumed by millions of daily active users
- Optimized SQL queries and indexing strategies reducing average query time by 60%
- Integrated third-party advertising networks and data providers
Technical Depth
Broad capability across the full engineering stack — with deep specialisation in backend systems, distributed infrastructure, and engineering leadership.
Core Technologies
Frameworks & Platforms
Cloud & Infrastructure
Performance & Observability
Data & Databases
Leadership & Delivery
Case Studies
Detailed write-ups of notable projects and technical challenges. Full case studies are in progress.
High-Throughput RTB Engine
Design and implementation of a real-time bidding engine capable of processing 500K+ bid requests per second at sub-10ms latency. Architected for horizontal scalability and resilience.
Bidding Pipeline Optimization
End-to-end latency reduction initiative that achieved a 72% improvement across the bidding stack through profiling, algorithmic changes, and infrastructure redesign.
Engineering Org Scale-up
Building 4 engineering teams from scratch — from hiring and onboarding through to establishing processes, technical standards, and a culture of delivery.
Writing
Technical articles on performance engineering, distributed systems, and engineering leadership. Articles are in draft — publishing soon.
Building RTB at 500K QPS: Lessons Learned
A deep dive into architecting a real-time bidding system that stays reliable under extreme load — covering queue design, latency budgets, and failure modes.
How We Cut Bidding Latency by 72%
The story of a multi-month performance initiative: from profiling and identifying bottlenecks to shipping optimizations that moved the needle significantly.
Scaling Engineering Teams Without Losing Culture
Growing from 2 engineers to 18 across 4 teams while preserving code quality, velocity, and team happiness. What worked and what didn't.
Prebid.js Deep Dive: Header Bidding Under the Hood
An inside look at how Prebid.js orchestrates header bidding across multiple demand partners, and lessons from contributing to the open-source project.
Get In Touch
Open to senior engineering leadership and R&D director opportunities. Feel free to reach out for collaboration or just to connect.
Phone
+1 431 294 7576Location
Oak Bluff, Manitoba, Canada