Software Engineer · Koehler Software
Tom Köhler
System architecture and security concepts for banks and public authorities – designed and built by a full-stack developer working with Java and Angular.
01 / Career
From junior developer to technical expert.
since 10/2026Founder · Koehler Software
Part-time: websites and software for small local businesses – with the same care as in large-scale projects.
since 03/2018Team lead
Professional, technical and line management of a team of up to 12 people; staff development and new organisational structures together with the management board.
since 10/2016IT consultancy, Rhine-Main area
From junior developer to technical expert and senior IT consultant – working in client projects as a developer and architect throughout.
2010 – 2016B.Sc. and M.Sc. in Computer Science
Darmstadt University of Applied Sciences
02 / Projects
Selected projects
since 07/2025Financial sector · Large international projectTechnical Expert · Software Architect
Turning requirements into system and interface specifications, modelling architecture and data flows, designing security concepts and implementing them across all layers.
Outcome: Technical link between the development team and stakeholders.
07/2024 – 06/2025Federal authorityLead Software Engineer · Backend
Designed and built an asynchronous messaging system connecting external service providers, migrated interfaces from SOAP to REST and modernised legacy code.
Outcome: Messaging with three service providers in production.
10/2023 – 06/2024Federal authorityLead Software Engineer · Frontend
Restructured the frontend and upgraded it to Angular 17, implemented new procedures, moved from SVN to Git with CI/CD.
Outcome: The authority’s first procedure running on Kubernetes.
07/2021 – 09/2023Major bankLead Software Engineer & Technical Project Lead
Evolved public-facing web applications and market data middleware and migrated them to the cloud.
Outcome: Numerous applications modernised from Angular 8 to 14.
Earlier projects (2016 – 2021)
- Major bank · Migration of the market data provider, Technical Project Lead
- Major bank · Editor for application journeys, replacing more than 40 legacy journeys
- Major bank · Retirement planning journeys and financial check, component libraries
- Building society · Four online sales journeys with REST integration
03 / Skills
Toolbox
Java Spring Boot Angular TypeScript RxJS Keycloak OpenID Connect Kafka RabbitMQ Docker Kubernetes Terraform GitLab CI MongoDB MariaDB Node.js
All skills in detail
Architecture
Software architecture · Microservices · API design · UML · Design Patterns · Requirements Engineering
Security
OAuth2 / OIDC · JWT · Keycloak · Threat Modeling
Backend
Java 8–17 · Spring Boot · JPA / Hibernate · REST · Kafka · RabbitMQ · Node.js
Frontend
Angular 2–18 · TypeScript · RxJS · Signals · Angular Material · SCSS · Storybook · Microfrontends
DevOps & Cloud
Docker · Kubernetes · Terraform · CI/CD · GitLab
Data, testing & methods
Oracle · MariaDB · MongoDB · JUnit · Jest · Scrum · Kanban · SAFe
German (native) · English (business fluent) · Professional Scrum Master
04 / Websites for businesses
Example sites coming soon.
Live demos for restaurants, hair salons and other businesses.
05 / Contact