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Project Experience

A selection of anonymized backend engineering, modernization, and integration projects in complex, business-critical environments.

Core themes

  • Java and Kotlin backend development in established systems
  • Safe modernization alongside ongoing product delivery
  • Reliable APIs, data flows, testing, and production operations

Modernizing a business-critical public-sector application

Technical modernization of an established Java application while ongoing domain and regulatory changes continued.

Results / operational benefits

  • Current Java, Jakarta EE, and application-server platform in production
  • Viable migration path for incrementally replacing EJB 2 persistence
  • EJB 2 and JPA operating side by side, with persistence behavior easier to verify automatically
  • Modernization alongside ongoing domain development

Evolving and modernizing a business-critical banking application

Java/JEE web application supporting internal customer-service and financial-services processes in a regulated environment.

Results / operational benefits

  • Reliable implementation of ongoing regulatory and technical changes
  • Java and framework upgrades running in production
  • Stronger automated test coverage
  • Stable build, deployment, and customer-service workflows

Building a scalable retail-media platform

Distributed Kotlin services, APIs, and data workflows forming the foundation of an integrated self-service platform.

Results / operational benefits

  • Extensible service foundation
  • Reliable interfaces and data workflows
  • Infrastructure defined and deployed reproducibly
  • Foundation for a self-service advertising platform

CRM-controlled portal onboarding & access control

A customer portal needed tight CRM integration.

Results / operational benefits

  • Clear approval process for sales without IT involvement
  • Consistent access control and feature visibility based on CRM data
  • Significantly less support effort around access and permissions
  • Traceable access logic through centrally controlled CRM-based policies

Cross-functional development for an international digital-health platform

Native iOS development as the primary responsibility, complemented by selected contributions to backend services, integrations, and production support.

Results / operational benefits

  • Continued development of the native iOS application for an international product
  • Support for multilingual product delivery
  • Targeted contributions to communication between the app and backend services
  • Cross-functional support for delivery, debugging, and production issues

What others say

  • Eliamo Touma
    Talent Specialist Lead

    “I've had the pleasure of working with Markus Krischke across two demanding projects, first in the banking sector and currently in the e-commerce domain. Markus is an exceptionally skilled Senior Backend Developer with over two decades of experience in software engineering, particularly in Java and Kotlin.

    What sets Markus apart is his ability to tackle complex technical challenges with clarity and precision. During our collaboration at ING, he played a key role in enhancing a critical web application used for internal banking operations, including account transactions, fraud case handling, and credit card management. His deep expertise in Spring Boot, Kafka, and microservices architecture was instrumental in delivering scalable and secure solutions.

    In our current e-commerce project, Markus continues to demonstrate his versatility. He develops robust backend features within a microservices setup, optimizes CI/CD pipelines, and ensures seamless service communication. His consulting skills are especially noteworthy; he excels at understanding business requirements, engaging stakeholders, and translating needs into strategic technical solutions.

    Beyond his technical capabilities, Markus brings outstanding soft skills to the table. He is structured, communicative, and highly proactive in agile environments. His experience working in international, remote teams makes him a reliable and collaborative team member.

    Markus is not only a top-tier developer but also a strategic thinker and trusted advisor. I wholeheartedly recommend him and look forward to future opportunities to work together.”

  • Gohar Gasparyan
    Senior Engineering Manager

    “I worked closely with Markus at Clue for a year and was lucky to be his manager. Markus is an exceptionally skilled senior iOS engineer. His work is clean, efficient and fast, always informed with best practices and lots of attention to detail.He is very passionate about iOS latest and greatest and besides can also help put on backend when needed.

    You can rely on him breaking down any complex task and handle on his own. He has been a great mentor for other teammates, reviewing and consulting them, but at the same time not imposing his views and letting them drive their own growth. Markus will always give an honest, unfiltered feedback and that has been of a great help for the team. I would highly recommend working with Markus.”

  • Florian Taufer
    Founder, Product Owner

    “Markus was an integral part of our small team that developed the multilingual software PINO-LA. This software enables efficient management of ETIM data, the global standard for product descriptions in the electrical industry.

    In his role as a software developer, Markus not only demonstrated his extensive programming expertise impressively, but also familiarized himself remarkably quickly with the complex subject matter of ETIM data. His commitment to also diving into the domain-specific details was a major advantage for the project.

    I would particularly like to highlight his strong understanding of the business requirements and his ability to contribute his own excellent ideas and solution proposals. This initiative and his analytical mindset significantly contributed to the success of the project.

    Working with Markus was always characterized by trust and a positive working atmosphere. I greatly valued his professional attitude, his reliability, and his ability to work effectively as part of a team.”
    (Translated from DE)

  • Emeline Cordat
    Senior Product Owner / Teamlead Product Management

    “I had the chance to work with Markus on various Apple applications (iOS mobile, tablet, and tvOS). Among other things, I shared with him a particularly exciting project: creating an Apple TV application from scratch. As a Product Owner, collaborating with Markus was an incredibly enriching and enjoyable experience.

    Markus is an exceptional developer, highly reliable, and truly passionate about delivering the best possible product to users. He doesn't just implement features: he puts himself in the users' shoes, constantly strives to understand their needs, and goes beyond expectations to provide tailored, relevant, and pragmatic solutions. He truly cares about improving the product, values good design, and knows how to identify and recommend quick wins.

    Beyond his impressive technical skills, Markus is also an exemplary colleague. His calm demeanor, total dedication to the project, efficiency, and ability to collaborate with team members make him a real cornerstone. He is a true team player - always ready to listen, share ideas, push the project in the right direction, and actively contribute to ensuring the team achieves its goals.

    Our collaboration was a real success overall, and in particular during the development of the search function for the Apple TV app, where we worked closely as a duo. Working with Markus was a genuine pleasure for me, and I can warmly recommend him to any team looking for a talented, pragmatic, passionate, and dedicated developer. He was a key contributor to the success of our Apple applications, and I am confident that he will continue to excel in any project he takes on, whether inside or outside the Apple world!”
    (Translated from FR)

  • Christian Storch
    Chief Technology Officer (CTO)

    “I had the pleasure of working with Markus and can confidently say he is an outstanding professional who consistently exceeds expectations. Proactive and forward-thinking, Markus tackles challenges head-on and drives initiatives independently, making a significant impact across teams.

    His expertise in mobile application architecture is remarkable. He led the development of a unified codebase for multiple brands and Apple platforms, enhancing our processes and improving scalability.

    What sets Markus apart is his ability to innovate. The "Magic Login" feature is a prime example; he conceived, designed, and guided it through patent filing, implementation, and cross-team adoption, showcasing his technical skills and collaborative spirit.

    Markus is a true leader who fosters innovation and delivers impactful results. I wholeheartedly endorse him for any role that requires expertise and leadership in mobile application development or technical architecture.”