Toralf Chryselius - IT Consultant in PKI Software Development

Q: Where is Toralf based?

Toralf is based in Hohen Neuendorf, Germany and can operate in on-site , hybrid , and remote work models.

Q: What languages does Toralf speak?

Toralf speaks the following languages: German (Native), English (Advanced) .

Q: How many years of experience does Toralf have?

Toralf has at least 29 years of experience. During this time, Toralf has worked in at least 18 different roles and for 13 different companies . The average length of individual experience is 1 year and 5 months . Note that Toralf may not have shared all experience and actually has more experience.

Q: What is Toralf's latest experience?

Toralf's most recent position is IT Consultant in PKI Software Development at BWI .

Q: What companies has Toralf worked for in recent years?

In recent years, Toralf has worked for BWI , Techniker Krankenkasse , BITMARCK , Ingrano GmbH , and Velamentum .

Q: Which industries is Toralf most experienced in?

Toralf is most experienced in industries like Information Technology , Government and Administration , and Education . Toralf also has some experience in Retail , Healthcare , and Telecommunication .

Q: Which business areas is Toralf most experienced in?

Toralf is most experienced in business areas like Information Technology , Product Development , and Project Management . Toralf also has some experience in Research and Development , Sales , and Operations .

Q: Which industries has Toralf worked in recently?

Toralf has recently worked in industries like Information Technology , Education , and Healthcare .

Q: Which business areas has Toralf worked in recently?

Toralf has recently worked in business areas like Information Technology , Product Development , and Research and Development .

Recommended expert

Hohen Neuendorf, Germany

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Experience

Jan 2025 - Nov 2025

11 months

IT Consultant in PKI Software Development

BWI

Implementation of a full-stack application with Angular as frontend framework and Java as backend language
Use of the Swagger OpenAPI specification for REST communication between frontend and backend application
Control of a card printer via the Nexus Card SDK framework
Design and implementation of a card management software with web interface and JavaFX module for printer monitoring
Use of Cucumber tests for test automation and creation of test artifacts for testing outside the development environment
Use of Wireshark for network investigations to analyze the API of a third-party product and to monitor the REST API of the self-developed software

Feb 2024 - Dec 2024

11 months

IT Consultant in PKI Software Development

BWI

Redevelopment of an existing software with the Spring Boot 3 framework
Control of a Thales HSM from Java
Development of GUI tools with JavaFX 24
Use of Wireshark to monitor the REST API of the self-developed software

Feb 2023 - Aug 2023

7 months

Software Architect (Subject Matter Expert)

Techniker Krankenkasse

Formulation of requirements for Android and iOS development in Kotlin and Swift within a sprint
Improvement of the TK-Safe app with a focus on vaccine individualization
Creation of Scrum stories and acceptance criteria for bug fixes and new features

Jan 2022 - Dec 2022

1 year

Freelance Java Developer

BITMARCK

Development of software for describing health data for health insurance companies on JBOSS servers with J2EE
Use of the BDD language Gherkin in Cucumber for end-to-end tests with Selenium for the web interface in Java
Implementation of Clean Code principles and loose coupling between frameworks

Sep 2021 - Dec 2021

4 months

Freelance Java and Groovy Developer

Ingrano GmbH

Further development of existing tests for Worldline GmbH
Addition of features to the crypto lib for creating RSA and ECC certificates in the X.509 domain
Revision of test design according to Clean Code paradigms

Apr 2021 - Aug 2021

5 months

Freelance Test Developer

Ingrano GmbH

Adapting and redeveloping tests for the KoCo connector based on field test errors and TÜV IT guidelines
Testing the cryptographic parameters of protected data transmission between the connector and the healthcare telematics infrastructure

Oct 2020 - Present

5 years 7 months

Developer and Training Lead

Velamentum

Development and redesign of the Velamentum ServerSuite as a full-stack project
Frontend: Angular 21 (TypeScript, CSS, HTML)
Backend: Go 1.25 with OpenAPI RESTful API
Development of a custom CA in Go to secure RESTful interfaces and generate third-party certificates via SCEP
Use of Podman containers instead of Docker for rootless systemd support
Automated distribution of root certificates to various client operating systems and browsers
Integration and use of OpenVAS, Wazuh, Suricata, ClamAV and Shuffle in custom-designed containers
Development of a training course with hardware (Raspberry Pi 5 or AMD64 systems) and training materials for hands-on network security

Sep 2019 - Mar 2021

1 year 7 months

Specification Engineer in the Patient Team

gematik GmbH

Further development of the specification for the architecture of the electronic patient record (ePA)
Managing the requirement lifecycle (AFOs) for ePA versions 1 through 5
Implementing fine-grained access control according to the Patient Data Protection Act in software architecture
Close coordination with spec writers of other components to ensure technology neutrality and compatibility

Jan 2019 - Present

7 years 4 months

Adjunct Lecturer for Computer Security, Penetration Testing and IT System Hardening

Code University Berlin

Development and delivery of a block seminar in English
Building a penetration testing lab (PenTestLab) as an open-source Java Spring Boot application for creating and provisioning virtual machines with Vagrant and Ansible
Integration and control of Metasploit, ZenMap, Armitage, OpenVAS, Snort, OSSEC and Graylog for hands-on training in attacks and monitoring

Jan 2017 - Aug 2019

2 years 8 months

Software Architect and Product Owner

T-Systems

Architecture and design of the T-Systems CA following Clean Code and SOLID principles for PKCS#12 containers and certificate packaging for terminal and card simulators
Role as Product Owner in the Scrum team (6–9 developers), occasionally taking on Scrum Master tasks
Design and development of an AdminCA in Java to generate valid and invalid X.509, CVC G1 and CVC G2 certificates using Spring 2 and Bouncy Castle

Jul 2016 - Dec 2016

6 months

C++ Developer in an Embedded Environment

T-Systems

Implementation of control routines for card terminals over the SICCT protocol to communicate with smart card crypto processors
Development environment: Eclipse, code versioning with Git, ticket system Jira, documentation in Confluence
Development in a Scrum process, tests in Gherkin with Cucumber, and implementation of Cucumber scanner routines in Java

Jul 2015 - Sep 2020

5 years 3 months

Managing Director and Developer

CSC

Design and development of the open source Velamentum Server Suite as Docker containers (12-factor app) for Intel and ARM hardware in SOHO environments
Development of a Velamentum CA in Go for issuing and actively distributing valid X.509 certificates, supporting SCEP and OCSP
Integration of OpenVAS, Snort, OSSEC, iRedMail, RoundCube, Rainloop, Nextcloud, OpenMediaVault, and Kodi as apps
Use of Jira, YouTrack, Git, GitLab, Docker registry, and Ansible for task management, versioning, image deployments, and DevOps support

Nov 2013 - Jun 2015

1 year 8 months

Software Architect and Developer in the PKI Environment

gematik GmbH

Design and implementation of a Gematik CA for X.509 and CV certificates, extending and later fully replacing the open source EJBCA components with custom code
Web interface in HTML/CSS with jQuery
Core: Java library for generating valid and invalid certificates according to X.509, CV G1, CV G2 with Brainpool curves
Creation of valid and invalid TSLs, using Bouncy Castle for cryptographic routines
Management with Maven and Ant, version control with Git/Gitblit, Jira in an agile Scrum process

Jan 2010 - Oct 2013

3 years 10 months

Freelance Software Architect and Developer

OpenLimit GmbH

Development of complex C++ and Java libraries for proprietary crypto software
Design of a signature service with a RESTful interface for a browser-based client
Development of the web GUI in HTML/CSS, porting console functionality to a web application with over 100 configurable parameters
Server-side JSF, database connectivity via JPA, communication with smart cards/HSMs via PKCS#11, version control with SCCS and Subversion

Oct 2009 - Jan 2015

5 years 4 months

Commercial Self-Employment in Crypto Software Design and Distribution

Self-employed

Design, development, and distribution of the Velamentum crypto software to protect computers against trojans
Design of a complex PKI with a central trust authority and smart card protection
Managed a team of one developer and one designer

Mar 2005 - Sep 2009

4 years 7 months

Programmer and software architect

Bundesdruckerei GmbH, Berlin

Design and programming of the Country-CA for Germany to generate ICAO-compliant CV certificates for passports
Development of cryptographic routines with Bouncy-Castle, GUI with SWT
Technical project management and implementation of a complex PKI

Jan 2005 - Feb 2005

2 months

Freelance programmer

Bundesdruckerei GmbH, Berlin

Worked on software to program the chips in electronic passports

Apr 2004 - Dec 2004

9 months

Author of a technical book on applied typography

Self-employed

Created a technical book on typography, font layout, and printing techniques
Used OpenOffice for prepress and professional typesetting

Apr 2002 - Mar 2004

2 years

Freelance software developer

Alcatel Berlin

Created a project study for internal communication between signal boxes (in English)
Implemented the Euroradio protocol for the Alcatel/Siemens communication stack
Coded communication between signal boxes using OpenSSL in C++
Designed a generic crypto communication stack, developed test routines for SIL 4 approval by the Federal Railway Authority
Ported open source software to a high-security hardware platform (Tagopert)
Worked in a team of about 85 people

Apr 1997 - Feb 2002

4 years 11 months

Freelance programmer

Self-employed

Programming in K&R C and C++ (MFC, STL) for retail (Lidl & Schwarz) and government agencies (BfA)
Porting code from C to C++ with consideration for the Y2K issue

Industry Experience

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

Experienced in Information Technology, Government and Administration, Education, Retail, Healthcare, and Telecommunication.

Information Technology

Government and Administration

Education

Retail

Healthcare

Telecommunication

Business Area Experience

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

Experienced in Information Technology, Product Development, Project Management, Research and Development, Sales, and Operations.

Information Technology

Product Development

Project Management

Research and Development

Sales

Operations

Summary

28 years of experience in software architecture and development in general cryptographic programming (symmetric, asymmetric, cryptographic securing of data transmissions, Public Key Infrastructures (PKI)) in C/C++, Java, Go, and Angular, design, programming, network design for the secure operation of active malicious machines, development of a full-stack application with Angular as frontend framework and Java and Go as backend languages, setup and operation of Certificate Authorities (CAs), penetration testing, project management for the product "T-Systems Connector", collaboration with gematik on the software and hardware specification for the "Electronic Health Record" project, test developer for the KoCo Connector, PKI software developer for HSM control from Java for key derivation, employee of the Techniker Krankenkasse for requirements gathering for PKI security of the Techniker Krankenkasse mobile app.
25 years of experience in software architecture and development in C/C++ and Java programming on Windows, Linux, and AIX including control of the operating systems' GUI variants.
16 years of experience in Java programming:
Storing data via the JPA interface
Spring Boot 3 framework
JavaFX GUI applications
Java 6, 7, 8, 9, 11, 13, 18, 21, 24 application design
Development of architecture and design of complex server applications with RESTful API
Use of the Swagger OpenAPI framework
Intensive use of the Bouncycastle library
JavaFX GUI development
13 years of experience using the JBOSS, Glassfish, and Wildfly application servers.
10 years of experience in smart card control, PKCS#7, PKCS#10, PKCS#11, and PKCS#15 APIs, control from Java and C++, ISO 7816 token.
12 years of experience with HTTP and CSS, setting up projects with the Bootstrap framework and with Angular.
10 years of experience with web service technologies SOAP, RESTful service (via Java Spring and Java Spring Boot).
10 years of experience implementing Clean Code paradigms (after R.C. Martin) and the SOLID principles in software, especially for loose coupling via interfaces and limiting responsibilities of Java classes.
7 years of experience working in Scrum teams as a developer (BITMARCK, Gematik, T-Systems) and as software architect and team lead PO (T-Systems).
5 years of experience developing WebGUI applications with Angular, JavaScript, jQuery with AJAX and client-side control of RESTful services.
5 years of experience with Docker and Podman as tools for isolated application execution on a machine and to support deployment processes.
5 years of experience with SQL using MS SQL, MySQL, PostgreSQL from Java and Python (Django).
5 years of experience in application programming with libraries from OpenSwan, IPSEC, OpenVPN, CyberGhost, DNSSEC, ISO-7816 token.
5 years of experience using and plugin programming vulnerability scanner OpenVAS; registered Open Source developer at Greenbone since 05/2015.
2 years of experience in Python programming (Django and Python control of websites and databases).
5 years of experience using the DevOps software Ansible in the software development process.
6 years of experience with Maven, SVN, Git, GitLab, Jira, Confluence (also as administrator); IDEs: Eclipse, IntelliJ IDEA, IntelliJ GoLang, IntelliJ PyCharm, Visual C++, MPS.
3 years of experience controlling the SICCT protocol in Java and C++.
3 years of experience creating, testing, and deploying Podman and Docker images to local registries, converting server software into 12-factor apps within Podman or Docker containers.
3 years of experience setting up and using local Podman and Docker registries (e.g., within GitLab), creating, testing, and deploying to local registries, converting server software into 12-factor apps within Podman or Docker containers.
2 years of experience implementing Domain Driven Design in Java, Go, and Angular.
3 years of experience implementing Behavior Driven Testing with the Gherkin flavors Cucumber for Go, Java, and TypeScript.
3 years of experience in front-end development with Angular 14, 15, 16, 17, 18, 19, 20, and 21.
4 years of experience in back-end development with Go.
3 years of experience in GUI development with JavaFX 24 and 25.

Skills

Operating Systems: Unix/linux (Ubuntu, Debian) +++ 26 Years.
Operating Systems: Windows (7, 8, 10, 11) +++ 25 Years.
Operating Systems: Mac Os (X) ++ 8 Years.
Operating Systems: Creating Custom Ubuntu Distributions ++ 6 Years.
Programming Languages/frameworks: Java +++ 15 Years.
Programming Languages/frameworks: C++ +++ 22 Years.
Programming Languages/frameworks: C (Ansi C, K & R C) +++ 6 Years.
Programming Languages/frameworks: Go +++ 5 Years.
Programming Languages/frameworks: Angular +++ 3 Years.
Programming Languages/frameworks: Typescript/css/html +++ 5 Years.
Programming Languages/frameworks: Admin Lte 3 For Angular +++ 5 Years.
Technologies: Uml +++ 13 Years.
Technologies: Domain Driven Design +++ 5 Years.
Technologies: Junit (Test-driven Development) +++ 10 Years.
Technologies: Test Driven Design +++ 5 Years.
Technologies: Gradle +++ 6 Years.
Technologies: Web Services ++ 4 Years.
Technologies: Ansible +++ 6 Years.
Technologies: Javafx ++ 2 Years.
Technologies: Java Ee Technologies +++ 7 Years.
Technologies: Spring Boot 2 And Spring Boot 3 +++ 6 Years.
Technologies: Hsm And Smart Card Programming Over Pkcs#11 Interface In Java +++ 7 Years.
Technologies: Cucumber With Java, Go, And Typescript +++ 5 Years.
Technologies: Selenium For Automated Web Testing +++ 5 Years.
Technologies: Parsing Certificates According To X.509 Standard +++ 9 Years.
Databases: Mysql/mariadb ++ 5 Years.
Databases: Oracle ++ 2 Years.
Databases: Postgresql ++ 6 Years.
Tools: Wireshark ++ 5 Years.
Tools: Jetbrains Intellij Ultimate And Eclipse (Angular, Html, Css, C++, Java, And Go) +++ 11 Years.
Tools: Together +++ 3 Years.
Tools: Enterprise Architect +++ 3 Years.
Tools: Clearcase ++ 3 Years.
Tools: Svn +++ 5 Years.
Tools: Confluence +++ 11 Years.
Tools: Git +++ 10 Years.
Tools: Crypto Library Bouncy-castle +++ 10 Years.
Tools: Maven, Gradle, Groovy +++ 8 Years.
Tools: Cmake +++ 8 Years.
Tools: Make +++ 10 Years.
Tools: Jira +++ 5 Years.
Tools: Confluence +++ 5 Years.
Tools: Openproject + 1 Year.
Products: Ms Office (Macro Creation) +++ 7 Years.
Products: Openoffice/libreoffice (Macro Creation) +++ 7 Years.
Others: Communication Protocol Tls +++ 16 Years.
Others: Preparing And Delivering Training In Cryptography, Office, And Pki +++ 13 Years.

Languages

German

Native

English

Advanced

Education

Sep 1990 - Mar 1997

Universität Rostock

Diploma Engineer · Electrical Engineering, specialization in communications engineering, focus on 'Secure Data Transmission' · Rostock, Germany · 1.4

Oct 1987 - Jun 1989

Brinkmann-Gymnasium Güstrow

Abitur · Güstrow, Germany · 1.2

Certifications & licenses

Professional Scrum Product Owner

Scrum.org

Professional Scrum Master

Scrum.org

Statistics

Experience

Total positions 20

Experience in Information Technology 16.5 y

Avg length 2 y 5 m

Longest experience 7 y 3 m

Expertise

Recent roles IT Consultant in PKI Software Development, Software Architect (Subject Matter Expert), Freelance Java Developer

Main industries Information Technology, Government and Administration, Education

Main business areas Information Technology, Product Development, Project Management

Qualifications

Highest degree Bachelor

Certifications earned 2

Profile

Created

February 2026

Last Update

April 2026

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Toralf based?

Toralf is based in Hohen Neuendorf, Germany and can operate in on-site, hybrid, and remote work models.

What languages does Toralf speak?

Toralf speaks the following languages: German (Native), English (Advanced).

How many years of experience does Toralf have?

Toralf has at least 29 years of experience. During this time, Toralf has worked in at least 18 different roles and for 13 different companies. The average length of individual experience is 1 year and 5 months. Note that Toralf may not have shared all experience and actually has more experience.

What roles would Toralf be best suited for?

Based on recent experience, Toralf would be well-suited for roles such as: IT Consultant in PKI Software Development, Software Architect (Subject Matter Expert), Freelance Java Developer.

What is Toralf's latest experience?

Toralf's most recent position is IT Consultant in PKI Software Development at BWI.

What companies has Toralf worked for in recent years?

In recent years, Toralf has worked for BWI, Techniker Krankenkasse, BITMARCK, Ingrano GmbH, and Velamentum.

Which industries is Toralf most experienced in?

Toralf is most experienced in industries like Information Technology, Government and Administration, and Education. Toralf also has some experience in Retail, Healthcare, and Telecommunication.

Which business areas is Toralf most experienced in?

Toralf is most experienced in business areas like Information Technology, Product Development, and Project Management. Toralf also has some experience in Research and Development, Sales, and Operations.

Which industries has Toralf worked in recently?

Toralf has recently worked in industries like Information Technology, Education, and Healthcare.

Which business areas has Toralf worked in recently?

Toralf has recently worked in business areas like Information Technology, Product Development, and Research and Development.

What is Toralf's education?

Toralf holds a Bachelor in Electrical Engineering, specialization in communications engineering, focus on 'Secure Data Transmission' from Universität Rostock.

Does Toralf have any certificates?

Toralf has 2 certificates. These include: Professional Scrum Product Owner and Professional Scrum Master.

What is the availability of Toralf?

Toralf is immediately available full-time for suitable projects.

What is the rate of Toralf?

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