Senior Java Developer (m/f/d)

About Virtual City Systems
Virtual City Systems (VCS) is a software company based in Berlin and Grafing near Munich.Since 2005, VCS has been supporting its customers in the creation, maintenance, and use of 3D city models. Initially operating as a service provider and software reseller, VCS has been developing its own 3D geodata infrastructure solution since 2013 for the management,visualization, and use of 3D geodata. Based upon which we have become one of the leading Urban Digital Twin solution provider in Germany.

Our customers are primarily municipalities and state surveying authorities, but increasingly also commercial enterprises seeking to implement digital 3D facility cadastres. Our solutions are based on well-known open-source projects such as CesiumJS, OpenLayers, and the 3D City Database, and we place a strong emphasis on open standards and interfaces such as OGC CityGML, OGC API Features, OGC WMS/WFS, OGC GeoJSON, OGC 3D Tiles, and others.

With the ongoing digitalization of public administration and current trend topics such as
Digital Twins, Urban Data Platforms, and Smart City projects, demand is increasing for
solutions that integrate 3D geodata with domain-specific applications in planning,
environment, simulation, land administration, and citizen participation. As a solution
provider and expert in 3D geoinformation, VCS is well positioned in this market and
continues to grow. We are therefore looking to strengthen our development team in the
areas of database development (3DCityDB and VC Database) and Java-based data
conversion processes.

• Your Responsibilities
  We are looking for a motivated and experienced Java Developer (m/f/d) to join our VC Suite development team. The focus of this role is the further development and maintenance of our VC Database (based on the open-source 3D City Database1) and our 3D Tiles converter. You will work on innovative Digital Twin solution and play a key role in the technical evolution of our software products. The topics include:- -----
• Further development and maintenance of the open-source solution 3D City
  Database (https://github.com/3dcitydb) and the VC Database built on it
•  Development, optimization, and maintenance of our 3D Tiles converter for
  converting various input data (vector data, CityGML, CityJSON) into the OGC 3D
  Tiles standard
• Collaboration within the VC Suite development team to continuously improve our
  software products
  - Design and development of web-based OGC interfaces, e.g. OGC API Features
  - Efficient processing of large data volumes (streaming, chunking, parallel
  algorithms)
  - Support of build, test, and deployment processes (CI/CD)
  Your Profile
  - Completed degree in Computer Science, Geoinformatics, or a comparable
  qualification
  - Strong expertise in PostgreSQL/PostGIS, particularly:
  o Design and implementation of relational database schemas
  o Development using SQL and PL/pgSQL
  o Use of spatial data types and functions
  - Very good knowledge of Java software development, including experience with:

         o JDBC
         o XML/JSON (including streaming, validation, schemas)
         o Concurrent programming and parallel algorithms
         o GIS libraries (e.g. GeoTools)
         o Computational geometry and geometry processing
         o Build tools (Gradle/Maven)
         o Automated testing (e.g. JUnit, Testcontainers)
         o Use of modern AI-assisted tools

- Experience in developing REST-based web services using OpenAPI, Spring, or JAX-
RS

- Experience working on larger software projects and confident handling of:
o Version control (e.g. Git)
o Containerization (e.g. Docker)
o CI/CD workflows (e.g. GitLab)
- Enthusiasm for programming, algorithmic challenges, open standards and data
models, and teamwork
- Independent and structured working style
- Ideally, experience with 3D GIS standards such as CityGML, CityJSON, and 3D Tiles,
as well as a general affinity for geospatial topics
- Very good English language skills, both written and spoken; German would be
welcome as well but not a must

What We Offer
- A full-time or part-time remote position
- A friendly and experienced team
- The opportunity to contribute your ideas to product development

Support for professional development and encouragement to contribute to open-
source projects