Hi. I'm Sebastian @sesigl Sigl 馃


Short Bio

I am a seasoned software engineer with over 18 years of experience across various domains. In recent years, my focus has been on high-load server-side projects, data- and machine-learning-driven applications, and platform development, where I love tinkering with infrastructure, containers, and Cloud Native technologies.

While there isn't a Wikipedia page about me (sorry folks!), a media bio is available below.


As a Staff Engineer at Adevinta, I have the honor of supporting multiple teams dedicated to delivering the best possible content based on first and third-party data. My primary focus is to support teams providing users with personalized content maximizing relevancy and revenue. I am privileged to empower multiple markets like Kleinanzeigen or Leboncoin two of the largest and most renowned classifieds markets in the world. Together, we aim to set new standards in user experience and drive impactful innovations within the industry.

As a result of the integration of various classifieds enterprises under Adevinta, we have emerged as the preeminent global leader in facilitating environmentally-conscious transactions of second-hand goods.

Technology is my driving force, and I firmly believe that anyone with a passion for it can learn to code. As a fervent advocate of this ideology, my heart lies in content creation. It affords me the opportunity to connect with like-minded individuals, stay up-to-date with the latest industry trends, and witness the growth of other tech enthusiasts - often younger generations - as they embark on their journey in this dynamic field. I am deeply inspired by the idea that we all stand on the shoulders of giants, and take great pride in observing the exponential expansion of our community.


  • Adevinta
    Dec 2022 Present
    MTS 2, Software Engineer
    As the Staff Engineer at Adevinta, it is my responsibility to create an exceptional search experience for advertising in Germany, which is seamlessly integrated into multiple digital marketplaces, each of them having millions of monthly active users. My focus is on building state-of-the-art solution that leverages the latest technologies to deliver the best content possible, which meet the needs of our users and exceed their expectations.
  • eBay
    Oct 2018 Dec 2022
    Classifieds Senior Full-Stack Engineer | Tech Lead Advertising
    As a senior Full-Stack Engineer and later as a tech-lead for advertising, I had the privilege of leading a talented team in the development of a cutting-edge global advertising configuration management system. With scalability and flexibility at the forefront of our approach, our system empowered yield experts to optimize revenue while maintaining maximum control.
  • Mister Spex
    Oct 2016 Sep 2018
    Senior Full-Stack Engineer
    As a Senior Full-Stack Engineer, I had the privilege of leading a team that spearheaded the evolution of essential features in our system. One of our most noteworthy accomplishments was the creation of an innovative augmented reality application that enabled our customers to virtually try on glasses. This technology played a pivotal role in transforming our primarily brick and mortar business into a digital-first enterprise.
  • Sopra Steria
    Oct 2014 Sep 2016
    Mid-Level Backend Engineer
    Sopra Steria
    As a Mid-Level Full-Stack Engineer, I had the opportunity to modernize a Java-Swing Application. With great attention to detail, I focused on extracting both frontend and backend components, resulting in a significant improvement in backend performance and frontend user-experience. Through advocating for a test-first mentality, I ensured that the components were not only successfully extracted from a big monolith but were also easier to change and caused fewer defects.
  • Freelance
    Oct 2005 Sep 2014
    High School, Computer Science Master & Freelancer
    From my teenage years onwards, coding has been my passion. At the age of 17, I took on the ambitious project of creating a Facebook clone for Turkey - a significant accomplishment that marked the beginning of my journey as a developer. Since then, I have continued to hone my skills by working for various companies on a contractual basis, all while pursuing my education.

Let's Connect

I'm excited to connect with others via email and Twitter to chat about projects and ideas. Currently, I'm not taking on freelance projects, but I am open to hearing about potential opportunities, discussing them with you and then potentially collaborating if it's a good fit.