Timo Külbel - Senior Fullstack Developer

Q: Where is Timo based?

Timo is based in Bremen, Germany and can operate in on-site , hybrid , and remote work models.

Q: What languages does Timo speak?

Timo speaks the following languages: German (Native), English (Advanced), Spanish (Elementary) .

Q: How many years of experience does Timo have?

Timo has at least 23 years of experience. During this time, Timo has worked in at least 12 different roles . The average length of individual experience is 1 year and 4 months . Note that Timo may not have shared all experience and actually has more experience.

Q: What is Timo's latest experience?

Timo's most recent position is Senior Fullstack Developer .

Q: Which industries is Timo most experienced in?

Timo is most experienced in industries like Information Technology , Transportation , and Construction . Timo also has some experience in Retail , Banking and Finance , and Automotive .

Q: Which business areas is Timo most experienced in?

Timo is most experienced in business areas like Information Technology , Product Development , and Operations . Timo also has some experience in Supply Chain Management , Project Management , and Business Intelligence .

Q: Which industries has Timo worked in recently?

Timo has recently worked in industries like Construction , Transportation , and Retail .

Q: Which business areas has Timo worked in recently?

Timo has recently worked in business areas like Information Technology , Operations , and Supply Chain Management .

Q: What is Timo's education?

Timo attended education in Business Informatics .

Recommended expert

Bremen, Germany

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Experience

Jan 2025 - Present

1 year 6 months

Senior Fullstack Developer

Lead Developer / Tech Lead in a large banking group to completely redevelop payment transaction systems
Redesign of payment processing using stream processing
Development and design of stream processing for international payments based on Kafka and Kafka Streams
Development of various input formats for the business department using Drools rules for dynamic adjustment of validation rules
Evaluation and comparison of various public cloud providers regarding the databases they offer
Technologies & Tools: Java 21, Kotlin, Spring Boot, Kafka, Kubernetes, Azure, TDD, JEE, REST, Angular, Spark, Google Cloud, SCDF, PostgreSQL, Drools, Git, S3, MongoDB

May 2024 - Nov 2024

7 months

Senior Fullstack Developer

Development and maintenance of a claims application based on the Faktorzehn claims system using Java, Spring Boot, and Vaadin
Development of business processes using Camunda
Development of asynchronous data interfaces to involved systems using Azure Service Bus
Development of Grafana dashboards for production monitoring
Role as Product Owner and Data Protection Officer
Team size: 12
Technologies & Tools: Java 17, Spring Boot, Vaadin, Azure, ArgoCD, Kubernetes, PostgreSQL, Camunda, Git, Faktorzehn, Azure Service Bus, Grafana, Octane

May 2023 - Dec 2023

8 months

Team Lead Data Migration

Technical Product Owner for data migration tickets
Supporting management, functional design teams, and business API analysts with functional and technical architecture questions
Creating the data migration architecture for two applications
Development and support of several backend tools for data migration using Spring Boot, Kotlin, and Oracle
Lead Developer for a 12-person development team
Team size: 15
Technologies & Tools: Kotlin, Spring Boot, Oracle, Azure, Kotlin Exposed, Azure DevOps, Git, Jira

Nov 2022 - Jun 2024

1 year 8 months

Senior Backend Developer and Data Engineer

Development and maintenance of backend applications using Spring Boot, Spring WebFlux, and Kotlin
Development of data pipelines using Spark and Scala
Optimization of analytical queries and full-text searches
Development and maintenance of data workflows using ArgoCD
CI/CD using Azure DevOps
Team size: 6
Technologies & Tools: Kotlin, Spring Boot, Spring WebFlux, Azure, CosmosDB, Azure Search, ArgoCD, Databricks, Apache Spark, Scala, Azure DevOps, Git

May 2022 - Nov 2022

7 months

Senior Software Developer

Migration of a C++-based CORBA payment procedure for unemployment benefits (approx. €15 billion annual payout) to Java EE 7
Programming of backend applications, microservices, and REST services using Java EE 7 APIs (EJB, JPA, JAX-RS, CDI)
Applying complex build processes (Maven, Git, Stash, Jenkins)
Debugging, profiling, testing, integration, and documentation of migrated software components
Team size: 14
Technologies & Tools: Java EE 7, EJB, JTA, JAXB, JAX-RS, JPA, CDI, Bean Validation, Interceptors, Managed Beans, Microservices, REST, Maven, Git, Jenkins, Mockito, Wiremock, Gatling

Mar 2021 - Jan 2022

11 months

Lead Backend Developer

Development of the backend component for a social network of a sustainable smartphone manufacturer
Integration of the system with Keycloak
Development of the backoffice GUI of the social network
Planning of the architecture for extending and further developing the application
Team size: 12
Technologies & tools: JHipster, Kotlin, Spring Boot, Angular, Keycloak, HATEOAS

Nov 2019 - Mar 2022

2 years 5 months

Fullstack Developer and Product Owner

Setup of a fully digital application process for a leasing company and integration into marketplaces
Support and further development of the digital application process
Design and development of a leasing and used car offering platform
Development of various interfaces to external and internal partners
Frontend development of the leasing configuration process
Product Owner for used car leasing
Team size: 15
Technologies & tools: Kotlin, Kubernetes, Azure, MongoDB (Cosmos), React, NATS, Redis, Camunda

May 2019 - Nov 2019

7 months

Technical Team Lead

Design, development, and operation of a pricing microservice
Maintenance of user stories in Jira
Development of backend pricing logic
Development of caching strategies
Team size: 4
Technologies & tools: Java, Kubernetes, Azure, MongoDB, Redis

Oct 2018 - Apr 2019

7 months

Senior Software Developer

Further development of a notification component for customer emails in a high-load scenario
New development of a push notification component
Performing DevOps activities: CI/CD, code, version, and release management
Team size: 8
Technologies & tools: Java, OpenShift, Google Firebase, JMS, ActiveMQ, Oracle

Apr 2018 - Sep 2018

6 months

Senior Software Developer

New development of a parcel shop finder with microservices
Creation of automated load tests for the parcel shop finder with Gatling
DevOps activities in the context of OpenShift
Development in test-driven development
Team size: 3
Technologies & tools: Kotlin, OpenShift, Spring Boot, MongoDB, Grafana, Gatling

Jan 2018 - Present

8 years 6 months

Freelance Developer

Development of various management tools for medium-sized companies (e.g. backend for an online massage booking platform, ERP for a sanitary company, warehouse management system for a moving company)
Development of an ERP system for multichannel supply for DIY and textile retail with API integration to Shopify, Etsy and Amazon as well as email integration via SendGrid
Technologies & Tools: JHipster, Kotlin, Spring Boot, Angular, Keycloak, PostgreSQL, Neo4J, DuckDB, GraphQL

Apr 2013 - Mar 2018

5 years

Lead Developer and Java Architect

Customization and further development of a fleet management software to build a fleet management service company
Deputy head of development at the software service provider
Technical project manager for the client
Lead developer of a sprint team
Security and data protection officer
Responsible for interface development (SOAP, REST), reporting and business documents
Further development, bug fixing and full-service calculations
Functional design of travel management billing
Team size: 7
Technologies & Tools: Java, Struts, Hibernate, Oracle, BIRT, SOAP, REST

Jun 2011 - Mar 2013

1 year 10 months

Senior Developer

Customization and further development of a claims management software for a motor vehicle B2B insurer
Technical project management for the client
Responsible for interface development (SOAP, REST)
Team size: 3
Technologies & Tools: Java, Struts, Hibernate, Oracle, BIRT, SOAP

Jan 2010 - May 2011

1 year 5 months

Senior Developer

International rollout of a fleet management solution in 26 countries
Development of various invoice importers and country-specific adjustments in invoice processing
Creation of CI/CD build processes
Development using test-driven development
Team size: 6
Technologies & Tools: Java, Struts, Hibernate, Oracle, BIRT

Jul 2009 - Dec 2009

6 months

Java Developer

Development of PDF statements using iText
Test-driven development
Architecture planning for extending the application
Internationalization and design of the PDF statements
Team size: 2
Technologies & Tools: Java, DB2, iText

Jul 2007 - Jun 2009

2 years

Java Developer

Development of web crawlers in the credit reporting area, including press crawlers
Operation and maintenance of imprint and company monitoring crawlers
Development of a frontend for research staff to evaluate the results
Integration of crawler execution into UC4
Team size: 2
Technologies & tools: Java, DB2, JSF, Lucene, UC4

Nov 2003 - Jun 2007

3 years 8 months

Software Architect

Responsible for the development and architecture of a ROLAP engine for analytical database marketing (target group segmentation, response analysis)
Coordinating test management with the client
Supporting the definition of target groups within the ROLAP engine
Architecture planning for application expansion
Test Driven Development
Team size: 6
Technologies & tools: Java, Struts, Hibernate, AspectJ, Oracle

Industry Experience

See where this freelancer has spent most of their professional time.

Experienced in Information Technology, Transportation, Construction, Retail, Banking and Finance, and Insurance.

Information Technology

Transportation

Construction

Retail

Banking and Finance

Insurance

Business Area Experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology, Product Development, Operations, Supply Chain Management, Project Management, and Business Intelligence.

Information Technology

Product Development

Operations

Supply Chain Management

Project Management

Business Intelligence

Skills

Top Skills

Java (22 Years)
Kotlin (7 Years)
Spring Boot (8 Years)
Kubernetes (4 Years)
Azure (6 Years)
Tdd (10 Years)
Jee (10 Years)
Rest (7 Years)
Angular (5 Years)
Spark (2 Years)

Industry Experience

Automotive (12 Years)
Leasing (5 Years)
Insurance (5 Years)
Credit Agency (2 Years)
E-Commerce (4 Years)
Shipping Logistics (1 Year)

Non-Dev Experience

Tech Lead (2 Years)
Technical Project Management (5 Years)
Product Owner (1 Year)
Data Protection Officer (1 Year)

Programming Languages

Java (=Excellent)
Kotlin (=Excellent)
Typescript (=Excellent)
Scala (=Medium)
Javascript (=Excellent)
Rust (=Basic)
Oracle (=Good)
Sql (=Excellent)
Postgres (=Good)
Mongodb (=Excellent)
Redis (=Medium)
Cosmosdb (=Medium)
Neo4j (=Basic)
Duckdb (=Excellent)

Databases

Oracle – Expert Level
Postgresql – Expert Level
Mysql – Basic Knowledge
Mssql – Advanced Knowledge
Mongodb – Expert Level
Arangodb – Basic Knowledge
Elasticsearch – Advanced Knowledge
Neo4j – Advanced Knowledge
Liquibase – Expert Level
Flyway – Expert Level

Frameworks

Angular – Advanced Knowledge
React – Advanced Knowledge
Spring Boot – Expert Level
Java Ee (Jakarta Ee) – Expert Level
Jax-Ws – Expert Level
Bootstrap – Basic Knowledge
Apache Camel – Basic Knowledge
Apache Wicket – Basic Knowledge
Google Web Toolkit (Bootstrap / Platform / Ext / Rpc) – Advanced Knowledge
Hibernate – Expert Level
Struts – Expert Level
Flutter – Basic Knowledge

Libraries

Rxjs – Basic Knowledge
Material-Ui – Basic Knowledge
Jquery – Basic Knowledge
Spring Data – Expert Level

Interfaces

Rest – Expert Level
Graphql – Expert Level
Grpc – Basic Knowledge
Soap – Expert Level
Openapi/Swagger – Expert Level

Cloud

Aws – Basic Knowledge
Azure – Expert Level
Openshift – Advanced Knowledge
Kubernetes – Expert Level

Testing

Selenium – Basic Knowledge
Jest – Basic Knowledge
Junit – Expert Level
Mockito – Expert Level
Wiremock – Expert Level
Postman – Expert Level
Soapui – Expert Level
Apache Jmeter – Basic Knowledge

Messaging

Apache Kafka – Basic Knowledge
Nats – Expert Level
Activemq – Advanced Knowledge
Redis – Expert Level
Jms – Advanced Knowledge

Operating Systems

Windows – Expert Level
Linux – Advanced Knowledge
Macos – Expert Level

Project Methods

Scrum – Expert Level
Kanban – Expert Level
Waterfall Model – Expert Level
V-Model – Expert Level
Spiral Model – Basic Knowledge

Tools

Git – Expert Level
Gitlab – Advanced Knowledge
Github – Basic Knowledge
Bitbucket – Basic Knowledge
Apache Subversion – Advanced Knowledge
Jira – Expert Level
Confluence – Expert Level
Trello – Expert Level
Sonarqube – Basic Knowledge
Docker – Advanced Knowledge
Jenkins – Advanced Knowledge
Apache Maven – Expert Level
Gradle – Advanced Knowledge
Terraform – Basic Knowledge
Glassfish – Basic Knowledge
Oracle Sql Developer – Expert Level
Jpa – Expert Level
Jsp – Expert Level
Keycloak – Advanced Knowledge

Platforms

Camunda – Expert Level
Cadence – Advanced Knowledge
Apache Kafka – Basic Knowledge

Concepts

Code Review – Expert Level
Pair Programming – Advanced Knowledge
Tdd – Test Driven Development – Expert Level
Clean Code – Expert Level
Solid – Expert Level
Bdd – Behavior-Driven Development – Advanced Knowledge
Responsive Design – Basic Knowledge
Component-Based Web Development – Expert Level
Redux – Basic Knowledge

Architecture Patterns

Domain-Driven Design (Ddd) – Advanced Knowledge
Microservices – Expert Level
Mvc (Model-View-Controller) – Expert Level
Mvvm (Model-View-Viewmodel) – Basic Knowledge

Ides

Intellij – Expert Level
Vscode – Advanced Knowledge
Eclipse – Expert Level

Other

Spring Eco – Expert Level
Ci/Cd Pipelines – Expert Level
Apache Tomcat – Expert Level
Apache Spark – Expert Level
Orm Modeling With Hibernate – Expert Level
Java Servlet – Expert Level
Websphere Application Server – Basic Knowledge
Extreme Programming (Xp) – Basic Knowledge
Oauth 2.0 / Openid Connect – Advanced Knowledge

Languages

German

Native

English

Advanced

Spanish

Elementary

Education

Diploma in Business Informatics · Business Informatics

Statistics

Experience

Total positions 17

Experience in Information Technology 16 y

Avg length 1 y 10 m

Longest experience 8 y 5 m

Expertise

Recent roles Senior Fullstack Developer, Team Lead Data Migration, Senior Backend Developer and Data Engineer

Main industries Information Technology, Transportation, Construction

Main business areas Information Technology, Product Development, Operations

Profile

Created

April 2025

Last Update

June 2026

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Frequently asked questions

Have questions? Find more information here.

Where is Timo based?

Timo is based in Bremen, Germany and can operate in on-site, hybrid, and remote work models.

What languages does Timo speak?

Timo speaks the following languages: German (Native), English (Advanced), Spanish (Elementary).

How many years of experience does Timo have?

Timo has at least 23 years of experience. During this time, Timo has worked in at least 12 different roles. The average length of individual experience is 1 year and 4 months. Note that Timo may not have shared all experience and actually has more experience.

What roles would Timo be best suited for?

Based on recent experience, Timo would be well-suited for roles such as: Senior Fullstack Developer, Team Lead Data Migration, Senior Backend Developer and Data Engineer.

What is Timo's latest experience?

Timo's most recent position is Senior Fullstack Developer.

Which industries is Timo most experienced in?

Timo is most experienced in industries like Information Technology, Transportation, and Construction. Timo also has some experience in Retail, Banking and Finance, and Automotive.

Which business areas is Timo most experienced in?

Timo is most experienced in business areas like Information Technology, Product Development, and Operations. Timo also has some experience in Supply Chain Management, Project Management, and Business Intelligence.

Which industries has Timo worked in recently?

Timo has recently worked in industries like Construction, Transportation, and Retail.

Which business areas has Timo worked in recently?

Timo has recently worked in business areas like Information Technology, Operations, and Supply Chain Management.

What is Timo's education?

Timo attended education in Business Informatics.

What is the availability of Timo?

Timo will be available full-time from January 2027.

What is the rate of Timo?

Timo's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.