Image of Stefan Lier
My name is Stefan Lier and I am a passionate technologist that is more interested in people and solutions than a certain tech stack. Driving culture, growth and personal development is my goal and technology the vehicle to help others grow and create a culture of knowledge sharing.
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What I've been up to lately

Tech Lead at Plancraft

Jan 2025 - Mar 2025

At Plancraft, I am leading the engineers in a cross-functional team. We are responsible to help our customer to make proper financial decisions and keep their financial health in check. We are using React, Typescript, and Firebase to build a web application that allows our customers to manage their finances and make informed decisions.

TerraformDockerGitCSS3ReactTypeScriptGoogle CloudPostgreSQLFirebase

Managing Sustainable Growth at Netlight

Oct 2014 - Aug 2024

Netlight is a company built and owned by its employees, fostering motivation for everyone to shape the company's future in alignment with their own needs, vision, and values. I was part of this journey for almost ten years, joining the German branch of Netlight when it had around 60 employees, to today, with over 700 active employees in Germany alone.

During this time, I played a vital role in growing the Hamburg office from 10 employees in 2016 to 170 employees in 2024. My key contributions to the office's growth included establishing a strong knowledge-sharing culture through various formats for consultants and other Netlight functions to exchange ideas, challenge each other, and learn through hands-on experience. I took an active role in hiring and developing new talent within Netlight, both in consulting and sales, while serving as a disciplinary leader for over six years. I worked to promote diversity in IT by establishing and supporting FINTA-related initiatives and projects in collaboration with local social organizations. Throughout my tenure, I successfully balanced business needs with talent and engagement management, creating an environment conducive to both personal and business growth.

Solution Architect

Feb 2024 - Aug 2024

In this role, I focused on aligning Macro-Architecture with product teams by working closely with technical and business leads to understand their requirements and needs, making decisive choices when necessary. I established guidelines for teams to follow and implement their services against, creating a unified product vision through automated API guideline enforcement. Working with the platform team, I co-created infrastructure improvements for all teams, adjusting and adding Terraform modules to align with architectural needs. I independently supported teams by migrating legacy services into containerized and self-contained systems based on Kotlin and Spring Boot, with an emphasis on quick turnaround times and minimal viable products.

KubernetesKotlinSpring BootTerraformDockerGitVue.jsCSS3NuxtTypeScriptGoogle CloudPostgreSQL

Product Architect

Jan 2023 - Jan 2024

As a Product Architect, I provided guidance for five application teams, aligning product architectures with the macro-architecture. I facilitated product-related and technical formats to understand needs and coordinate implementation efforts. Being part of the teams allowed me to maintain proximity and ensure alignment between micro and macro architectures. My approach facilitated swift decision-making and effective development coordination, fostering a culture of knowledge sharing across teams.

KubernetesTerraformDockerGitMicrosoft AzureApache KafkaGNU Bash

Team and Tech Lead

Jul 2022 - Dec 2022

As technical lead, I guided a team of 3 engineers to drive company-wide cloud adoption through SRE concepts and individual developer and product owner tutoring. I developed a comprehensive cloud migration vision in collaboration with Project Management, Product Owners, and technical stakeholders. Using Kotlin and Spring Boot, I implemented a cloud solution from scratch, coordinating needs and requirements across all parties while establishing the infrastructure for immediate user impact. I developed a self-contained system driven by domain-driven design and an iterative approach, demonstrating the feasibility of this relatively new methodology while ensuring quick user impact.

KotlinSpring BootReactCSS3TypeScriptTerraformDockerGitGoogle CloudApache Kafka

Site Reliability Engineer

Aug 2021 - Dec 2021

I was responsible for creating reusable components, automated infrastructure in Terraform, facilitated fast onboarding and deployment for teams. I started an internal open-source initiative, fostering knowledge and code sharing across teams. I connected development teams to share best practices, driving knowledge sharing through various channels and supporting site reliability efforts.

Microsoft AzureTerraformDockerGitApache KafkaPostgreSQL

Solution Architect

Jan 2021 - Jul 2021

I played a crucial role in defining technical infrastructure and architectural guidelines, enabling scalable and maintainable application landscapes. My focus on implementation speed without sacrificing quality ensured rapid end user acceptance. Facilitating technical discussions and embracing a cloud-native approach, I helped create a low-maintenance infrastructure and drove development with a pragmatic approach.

JavaRabbitMQ

Solution Architect

Jun 2020 - Dec 2020

Coordinating the architecture for an IoT platform across different subsidiaries, I led discussions towards a unified system. My collaboration with product leads ensured alignment with market needs and integration of diverse solutions. My expertise facilitated the development of a flexible and scalable platform capable of meeting various market demands.

Technical Lead

Jun 2019 - Apr 2020

In this position, I spearheaded the creation of a new MVP product from the ground up, leading a cross-functional team as a full-stack engineer covering both infrastructure and Frontend development. I architected and implemented a scalable microservices system hosted in Kubernetes to facilitate market entry. Through iterative development of full-stack applications using Kotlin and React, I enabled quick evaluation of assumptions and rapid time-to-market for the new product. I enhanced operational efficiency by implementing comprehensive technical and product metrics, displaying them in Operational Dashboards for monitoring purposes. The MVP was successfully delivered within 5 months, launching just before the Christmas peak-travel season, progressing from initial ideation to a robust cloud-native application.

KotlinReactCSS3TypeScriptTerraformDockerGitMicrosoft AzureApache KafkaPostgreSQLAmazon Web Services

Full Stack Developer

Jan 2018 - May 2019

Working within a cross-functional team, I evaluated and integrated external marketing software, including essential business logic. I developed scalable services using cloud-infrastructure and Kotlin to meet both organizational and customer demands. My focus included automating infrastructure-as-code principles to streamline continuous integration and deployment processes. I improved project maintainability and stability by introducing comprehensive automated testing of interfaces, contracts, and service integrations.

KotlinSpring BootReactCSS3TypeScriptTerraformDockerGitAmazon Web ServicesApache Kafka

Technical Product Owner

May 2017 - Dec 2017

I managed the current state and advanced it to meet new requirements, including communication with internal and external IT-providers and development teams to align their requirements. I created a new infrastructure vision by bridging the gap between internal IT and the project team, optimizing the infrastructure platform to match the needs of the development teams and their product.

Platform Engineer

Aug 2016 - Apr 2017

In this role, I maintained and advanced the current infrastructure throughout the development cycle, including automating the provisioning and deployment measurements and orchestration of services. I implemented automatic collection and processing of application and infrastructure metrics and logs, enabling the project team to monitor application state and track malfunctions during runtime.

AnsibleGNU BashPythonDockerGitAmazon Web Services

Full Stack Developer

Oct 2014 - Jul 2016

I significantly improved website performance and user interactions by eliminating obsolete technology and enforcing standards with third-party vendors, achieving a tenfold increase in meaningful first paint. Using Scala and NodeJS, I developed services to transition legacy application code toward a microservice architecture, enabling easily maintainable, small artifacts with multiple daily deployments instead of bi-weekly releases. I established common front-end workflows and created pattern and component libraries for an in-house built framework, leveraging ES2015 instead of jQuery.

HTML5JavaScriptCSS3Node.jsScalaJavaDockerGit