Consulting

I help companies build efficient, flexible and architecturally-sound data streaming platforms

I have spent the last 10 years of my career building data streaming systems. I keep seeing the same challenges:

  • Disconnect between the application and data / analytical teams. Upstream schema changes that break data pipelines.
  • Apache Kafka at the top of the infrastructure bill. Sometimes without clear cost attribution.
  • New projects that rely on the data platform take forever to complete.
  • Popular data processing frameworks that require enormous amount of compute even for moderate datasets.
  • Layers of competing technologies due to migrations, acquisitions, and reorgs. Poorly chosen tools based on habits, not research and benchmarks.
  • Data analysts and data scientists are responsible for managing complex infrastructure without proper training.

What I offer

I work with your team to improve the architecture and efficiency of your data streaming systems.

Here are some examples of the work I’ve delivered for my clients:

  • Improved performance of a complex Flink job, bringing the cost down.
  • Designed and developed a specialized stream-processing framework using Rust, Arrow and DataFusion.
  • Advised a team on how to ingest mutable streams from Kafka into ClickHouse using Flink.
  • Educated a team on how to use profiling and benchmarking for complex Flink pipelines.
  • Advised a team on how to design efficient Change Data Capture process for Postgres using Flink CDC.
  • Ran workshops on Scala and Akka.
  • Ran training and bootcamps on Apache Flink.

Background

I'm a software engineer & architect specializing in data-intensive applications: data platform engineering, data streaming, stream processing, and distributed systems.

I was a tech lead at Activision and Shopify, and a founding engineer at a data infrastructure startup Goldsky.

I've designed and built data platforms end-to-end: data instrumentation and ingestion, data processing, analytics, data lakes and warehouses, OLAP databases, data products. For the past 10 years, I've been primarily focused on data streaming, stream-processing and realtime data pipelines. I have a lot of experience with Apache Kafka and Apache Flink, but I've worked with a variety of technologies, and have solid understanding of most of the popular (and not so popular) streaming platforms and frameworks.

Recently I founded Irontools, where I build complex extensions for Apache Flink.

How I work

Depending on my availability and your needs, we can choose a few ways to collaborate:

  • Advisory role. I meet with your team weekly, and I'm available for questions 24/7. This works well for sharing best practices, guiding technical roadmap, high-level strategy discussions, and ongoing operational support
  • Hands-on role. I work with your team 1-2 days a week. This is ideal for collaborating on important deliverables, performance optimization work, and greenfield projects.
  • Training. I craft a custom workshop for your team.

Contact

Email me at yaroslav@irontools.dev.

Testimonials

Hojjat Jafarpour

"Yaroslav's knowledge of Flink, Kafka, and ClickHouse is outstanding. His consulting sessions are packed with practical advice, best practices, and forward-looking insights. Highly recommended for anyone building real-time data platforms."

Hojjat Jafarpour

CEO @ DeltaStream

Ryan Self

"Yaroslav was a key advocate for Flink during his tenure as a full-time employee at Shopify, and during his later consulting contract with our customer data platform team, his deep expertise greatly benefited us. His insightful recommendations led to real improvements in our Flink pipelines and helped us work together more smoothly during on-call shifts."

Ryan Self

Senior Data Engineer @ Shopify

Wasif Aleem

"Yaroslav is one of the deepest practitioners and has run data streaming systems in production at scale, with hands-on expertise across Flink, Kafka, Spark, and Iceberg. What sets him apart is his judgment, reading system behavior to identify noise from bottlenecks, distinguishing architectural limits from low-level performance tuning, and knowing which tradeoffs really matter.

Working with him to push Flink, Spark, Kafka Connect, Debezium, and Supermetal to their limits was genuinely fun. He's a professional with sharp instincts who delivered ahead of schedule. I'd work with him again without hesitation."

Wasif Aleem

Co-Founder and CTO @ Supermetal

Otto Remse

"I had the privilege of working with Yaroslav as a consultant on one of the Nordic region's largest e-commerce database projects. His expert knowledge of Apache Flink proved invaluable to our search team's success. Yaroslav demonstrated exceptional technical acumen in identifying and resolving performance bottlenecks, ultimately delivering a 50% improvement in system performance while simultaneously reducing operational costs.

Yaroslav has deep technical expertise and can effectively diagnose complex issues and implement practical solutions. This combined with exceptional professionalism sets him apart from others."

Otto Remse

Data Engineer / Cloud Architect

Jeff Ling

"Yaroslav’s ability to balance business need with deeply technical solutions is an incredible supplement for fast moving teams. It’s easy to shift from a breadth-first research mode into a deep implementation mode, but he brings the unique ability to shift from deep work back to breadth first to maximize his own technical contributions based on the team’s goals."

Jeff Ling

CTO @ Goldsky

Sujay Jain

"I’ve been running large-scale streaming systems for years, and Yaroslav consistently stands out as someone who really understands Flink. His experience with stateful stream processing, best practices, and production patterns goes beyond what you typically see in documentation. The Advanced Apache Flink course looks genuinely useful for anyone looking to level up."

Sujay Jain

Senior Software Engineer @ Netflix

Ryan van Huuksloot

"I had the privilege of working with Yaroslav Tkachenko at Shopify, and it's rare to find someone with his depth of expertise across the entire streaming stack combined with an exceptional ability to make complex topics accessible. If you're serious about mastering streaming technologies, learning from someone with Yaroslav's real-world, battle-tested experience is an opportunity you don't want to miss."

Ryan van Huuksloot

Staff Engineer @ Shopify

Dionysios Stolis

"An excellent training for anyone looking to master Apache Flink. Yaroslav guided us from understanding Flink internals and the core codebase all the way to practical deployment techniques. If you want to move beyond the basics and understand how Flink actually works under the hood, this is the course to take."

Dionysios Stolis

Machine Learning Engineer @ Just Eat