Julius Seporaitis
on hobbies and work


I have 16 years of wide ranging software engineering experience. The large part of this time was spent in startups and early stage companies. Twice I was an engineer #1 in a startup. I have also worked as a freelancer and in mid-sized companies with sizeable engineering teams. I am a strong individual contributor and engineering manager, with a product mindset.

If you are interested in knowing more about my actual skills, you should connect or read my full resume on LinkedIn.

Below are some informal highlights from most recent work.


Lyst is a fashion search platform offering shoppers to find the best priced fashion items among the catalog of millions of products from thousands of retailers across the world. I joined as a Senior Software Engineer II in a team responsible for enrichment and deduplication of product data. Within a year I was the team lead. The first nine months of my tenure was defined by hands-on work, but the second part - more leadership and indirect influence. Key highlights:

  • Lyst is a first company where I managed myself out of a team, positively. I transformed the team from followers and executors of top-down decisions, to a team of proactive participants who are capable of defining their own metrics to track business objectives and tactics to impact them. The internal team health metrics were consistently well above industry and the company average (8 or more out of 10).
  • My proudest moment following the above transformation was - the team solved a notoriously elusive deduplication problem that plagued product catalog for years, but noone successfully tackled it until then. They did it end-to-end on their own, my job was to provide context, facilitation and guardrails.
  • I coached and/or mentored my colleagues on topics ranging from basic software engineering skills, to management, including difficult conversations (addressing poor performance, and firing someone).
  • Two projects I lead saved the company up to a $400'000 per year.


genus.ai helps marketing teams engage their customers effectively, using behavioral science based machine learning models. I joined as a software engineer to build out the prototype into a working product, setup tools, and processes, hire and look after the team. My key highlights:

  • Process-wise, I optimized for iteration speed. It takes between 5 and 15 minutes to deploy a change to production, including building, testing, security, and safety checks.
  • Security-wise, I got buy-in from the C-suite and I implemented extra steps on multiple levels to prevent, detect, and deflect common attack vectors. This directly helped sign large corporate clients, who always do a vendor security assessment.
  • It is my first dip in a leadership role as Head of Engineering. It pushed me to better understand myself and my preferred leadership style: transformative, leading by example - "do as I do", and enabler, looking for waste in processes and tools, and trying to unblock them.


Onefinestay is an online private home rental platform, akin to Airbnb, but focusing on luxury homes. Unfortunately, the engineering team in London has been dissolved and my tenure there was short. Regardless, I enjoyed working with the team, and it was also a career challenge. Coming from a complete greenfield project at YPlan, to a company with an established product, can I make a meaningful difference? These are my highlights:

  • Applied my learnings from YPlan and made the deployment process completely automatic.
  • Developed a new website, with inventory from all three companies, two weeks ahead of schedule, under a tight deadline. We did it as a team and had a lot of fun doing it.
  • After the data science team has been dissolved, on personal initiative, I took over and successfully maintained Apache Airflow based workflows, without any documentation or support.


YPlan was an events discovery and booking service from 2012 until it was acquired by TimeOut in 2016. Despite it being a financially unsuccessful acquisition, with bitter news coverage, I learned a lot at YPlan about the startup rollercoaster, engineering, and teamwork. Many of my colleagues went on to work at Facebook, Google, QuantumBlack, Uber, Ubuntu, and Microsoft, so I have been massively privileged to work with and learn from them. Engineering wise, I am most proud of:

  • Building out the infrastructure on AWS from scratch. It largely remained the same throughout the company's lifetime. It has been covered in an AWS Case Study. Also, a simple plugin yum-s3-iam, from the early days of YPlan surprisingly continues to be popular.
  • Advocating internally and implementing continuous deployment (a summary by my former colleague here) and stage-less release process (also, described here).
  • Setting up Phabricator for code reviews and task tracking. It contributed to the engineering speed (here is a good explanation of difference to pull requests). It also remains difficult to explain to anyone who has not tried it, but the slight shift in the workflow has enabled a culture of rapid and bold experimentation.