Professional Java Developer; f​/m​/d at established IT-Security

Professional Java Developer (f/m/d) at an established IT-Security Company

Join to apply for the Professional Java Developer (f/m/d) role at Zertificon Solutions GmbH.

Zertificon Solutions – Software Manufacturer since 2004. We are IT security specialists: our products encrypt business communications. More than 25% of the 100 highest‑revenue companies in Germany, as well as hundreds of medium‑sized enterprises across all industries, already use our Z1 encryption solutions. We have big plans and continue to grow steadily. Nearly 140 employees are already working with us in Neukölln.

Join our professional, highly qualified team: take on challenges, share your knowledge, learn new things, and discover your potential!

• Develop and maintain new, containerized services that make communication secure for everyone.
• Proactively develop and plan our enterprise products, finding new ways and solutions to create bleeding‑edge products.
• Analyze potential issues or blockers within the development strategy and plan and act in prevention.
• Act as an effective coordinator with the team interacting with internal stakeholders.
• Align your work with other RND teams to ensure that your product and its components fit into the overall development architecture.
• Be part of a cross‑functional team, not shying away from new technologies and thought patterns.

• At least 4 years of experience working in a development team and delivering solutions and products.
• At least 2 years of practical experience working with Java (Java 11/17/21).
• Deep knowledge of software architectures like monoliths and microservices.
• Experience with security technologies such as PKI, S/Mime, OpenPGP, X.509 certificates, PGP keys.
• Ideal: knowledge about Email, SMTP, Java Mail, and Bouncy castle.
• Good level of English (at least B2).

• Linux:
  Basic proficiency in Linux commands.
• Shell Scripting: ANSI Shell, Bash.
• Frameworks:
  Spring MVC, Spring Boot, Spring Data, Spring Integration.
• Microservice Design:
  Experience with microservice architecture.
• Monoliths:
  Experience with monolithic applications.
• Build Tools:
  Gradle, Maven.
• Software Testing Methodologies.

• Flexible working hours and home office possible.
• Mobility: free Germany ticket, job bike leasing or car parking.
• Allowances for food (e.g. Lieferando) and internet in the home office.
• Benefits in the office: roof terraces & green courtyard, organic fruit and drinks, parcel acceptance.
• Get‑together: pizza Friday in the office, regular team events, big summer party.

• Independent & committed:
  For over 20 years, we’ve built secure communication tools as an owner‑managed company with a clear stance.
• Purpose‑driven:
  We believe digital communication must be secure and free. If you support whistleblowing, we might share the same values. We donate €1,000 to an organization that supports Edward Snowden for every new hire who mentions him in their application.
• Hands‑on excellence:
  We tackle complex challenges and build the best ourselves.
• Agile by conviction:
  No bloated processes; initiative is welcome but will be challenged to ensure quality.
• Security that works:
  We build software that’s secure and usable for both large enterprises and smaller businesses.
• Diverse & international:
  Our team of 130 people from 30+ countries shares one mission: making secure digital communication accessible to businesses of all sizes.

If that resonates with you, we’d love to hear from you. Please have a look at our Work at Zertificon page:  For questions, you can reach our HR team at