Freiberuflicher Security- und Software Engineer.
Aktualisiert am 10.03.2025
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 01.07.2025
Verfügbar zu: 100%
davon vor Ort: 10%
IT-Security
SIEM
Python
Rust
Docker
AWS
Agile Softwareentwicklung
PostgreSQL
Redis
DevOps
REST
Security Konzepte
Ansible
Terraform
German
Native Speaker
English
Experienced speaker with full working proficiency

Einsatzorte

Einsatzorte

Mainz (+10km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

3 Monate
2025-01 - heute

Analysis, refinement, and creation of new SOC workfolows

Cybersecurity Consultant SOC
Cybersecurity Consultant SOC
  • This includes the development of standard operating procedures and playbooks
  • Analysis, refinement, and creation of new of company security policies
  • Support SOC operation through best practice and clear process documentation
Liebherr?IT Services GmbH
4 Jahre 6 Monate
2020-10 - heute

SORMAS

Software Engineer Java Python Docker ...
Software Engineer

Kernentwickler von SORMAS, einer open-source e-Health Lösung die sowohl in Gesundheitsämtern als auch international zur COVID-19 Pandemiebekämpfung eingesetzt wird. Hauptaufgaben waren Design und Implementierung von

  • "Sormas2Sormas", welches das einfache Teilen von Falldaten ermöglicht.
  • einem Audit Systems welches sicherheitsrelevante Informationen aufzeichnet.
  • einer Schnittstelle zu einem Fallmelde-Tool.

GitHub Git IntelliJ Atlassian JIRA Atlassian Confluence
Java Python Docker PostgreSQL Keycloak etcd
vitagroup AG
Remote
1 Jahr 9 Monate
2023-04 - 2024-12

Monitoring of security relevants events in SIEM and EDR

SOC Analyst
SOC Analyst
  • Analysis and response to detected security incidents.
  • Optimization of detection processes and implementation of countermeasures.
  • Threat intelligence, threat hunting, and detection engineering.
Liebherr?IT Services GmbH
Remote
2 Jahre
2021-04 - 2023-03

open?source software system to support public health departments

Software Engineer Docker JavaEE etcd ...
Software Engineer
  • SORMAS core?team developer:
    • ?SORMAS is an open?source software system to support public health departments all over the world in their fight against the Covid?19 pandemic and beyond.
  • Main contribution was the design and implementation of:
    • Sormas2Sormas, which enables frictionless sharing of Covid?19 case data between public health offices.
    • An auditing subsystem, which records all relevant system operations and user interactions.
Docker JavaEE etcd Keycloak PostgreSQL
Vitagroup AG
Remote
6 Monate
2020-10 - 2021-03

implementation of an interface to the German case reporting tool

Software Engineer Docker JavaEE Spring Boot ...
Software Engineer
  • SORMAS core?team developer:
    • SORMAS is an open?source software system to support public health departments all over the world in their fight against the Covid?19 pandemic and beyond.
  • Main contribution was to support the implementation of an interface to the German case reporting tool.
Docker JavaEE Spring Boot and PostgreSQL PostgreSQL
IMIS Infektionsübermittlung GbR
Remote
6 Monate
2020-04 - 2020-09

Design and implementation of a SIEM and log collection system

Junior IT?Security Engineer ?
Junior IT?Security Engineer ?
  • Design and implementation of a SIEM and log collection system tailored to the needs of industrial networks based on Elasticsearch
KORAMIS GmbH
Saarbrücken, Germany
2 Jahre
2018-04 - 2020-03

Implementation of automated security solutions

Working Student: IT?Security Engineer
Working Student: IT?Security Engineer
  • Implementation of automated security solutions. Design and implementation of a SIEM system based on Elasticsearch, Logstash, and Kibana (ELK?Stack). Deployment with Terraform and Ansible to AWS.
  • IT?Security maintenance and incident response.
  • Penetration testing of internal and production systems.
  • Development of internal tooling in Python. Deyployment to Kubernetes cluster
FlixBus/FlixMobility GmbH
Remote
1 Monat
2018-04 - 2018-04

Supervision of a workshop series? practical part

Instructor
Instructor
  • Supervision of a workshop series? practical part concerning smartphone usage and cyber security for elderly people.
Verbraucherzentrale Saarland (Consumer advice center)
Saarbrücken, Germany
5 Monate
2017-11 - 2018-03

IT?Administration

Student Assistan
Student Assistan
  • Website/Database administration and IT infrastructure maintenance
Saarland University, Faculty of Philosophy
Saarbrücken, Germany
3 Jahre
2015-04 - 2018-03

Reverse engineering/Security testing of Android apps

Student Assistant - Research
Student Assistant - Research
  • Reverse engineering/Security testing of Android apps to research malicious advertisement libraries.
  • Design and implementation of an Android?specific fuzz testing framework.
  • Prototyping of a privacy analysis tool in C# using MariaDB as persistence.
Saarland University/Center for IT?Security, Privacy, and Accountability (CISPA)
Saarbrücken, Germany
6 Monate
2016-04 - 2016-09

foundation lecture Programming 2

Student Assistant: Tutor Programming Lecture
Student Assistant: Tutor Programming Lecture
Saarland University, Compiler Design Lab
Saarbrücken, Germany

Aus- und Weiterbildung

Aus- und Weiterbildung

2 Jahre 8 Monate
2019-10 - 2022-05

Computer Science

M.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of cybersecurity
  • Advanced courses in mobile, embedded, web, and usable security
  • MASTER THESiS on request
1 Jahr
2018-10 - 2019-09

Entrepreneurial Cybersecurity

M.Eng., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Eng.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on aspects of cybersecurity and computer science in combination with a business start?up project.
6 Monate
2018-04 - 2018-09

Computer Science

M.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of computer science.
  • Intermediate study to bridge the time till the start of the Entrepreneurial Cybersecurity Master Program
3 Jahre 6 Monate
2014-10 - 2018-03

Cybersecurity

B.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
B.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of cybersecurity and computer science
  • BACHELOR THESiS on request
7 Jahre 11 Monate
2006-08 - 2014-06

German high?school

diploma (Abitur), Albertus?Magnus?Gymnasium, St. Ingbert, Germany
diploma (Abitur)
Albertus?Magnus?Gymnasium, St. Ingbert, Germany

Advanced classes (Erweiterungskurse): 

  • Mathematics 
  • German

Position

Position

  • SECURiTY ENGiNEER
  • SOFTWARE ENGiNEER

Kompetenzen

Kompetenzen

Top-Skills

IT-Security SIEM Python Rust Docker AWS Agile Softwareentwicklung PostgreSQL Redis DevOps REST Security Konzepte Ansible Terraform

Schwerpunkte

  • Security Engineering:
    • Design and implementation of SIEM systems including log collection, processing, and enrichment.
  • SOC Analyst:
    • Hunting of cyber threats, swift analysis, and effective incident response. SIEM, EDR, and threat intel.
  • Security Enthusiast:
    • Strong focus on system and application security. Special interested in the design of secure software systems.
  • Software Engineering:
    • Implementation of reliable server backends and tooling in Java, Rust, and Python. Worked on a pandemic management system during the Covid?19 global pandemic.
  • Software Architecture:
    • ?Creation of clean and durable architectures, with expertise in evaluating suitable frameworks that align with project goals and requirements.

Produkte / Standards / Erfahrungen / Methoden

GitHub
Experte
Git
Experte
Ansible
Experte
Terraform
Experte
TOOLS/METHODS

DevOps:

  • Docker (?compose) and Kubernetes
  • Ansible 
  • Terraform
  • GitLab
  • Jenkins
  • GitHub 
  • GitHub Actions CI/CD pipeline


Agile:

  • Several years of working experience in agile environments using Scrum
  • Test Driven Development:
    • Knowledgeable of TDD


Office skills:

  • Familiar with all major office suites and applications


SECURiTY

Security generalist:

  • Strong familiarity with security concepts, principles, and best practices
  • Areas of expertise include system, application, and web security


SIEM:

  • Advanced knowledge of use, operation, and maintenance of the Elastic stack, especially in the context of SIEM
  • I designed two SIEM systems so far


Incident Response:

  • Advanced knowledge of incident response processes, MITRE ATT&CK® framework, threat intelligence management, and EDR
  • Hunting of cyber threats, swift analysis, and effective incident response


App reverse engineering:

  • Security analysis of Android apps while working as student assistant


Access control mechanisms:

  • I am strongly familiar with both, theoretical background and technical realization, of OS access control systems
  • Familiar with SELinux/SEAndroid and Fuchsia object capabilities


SOFT SKiLLS

Adaptability:

  • As shown by my track record, I am used to adapt to new sectors, domains, and projects within a short amount of time


Analytical thinking:

  • Skilled in dissecting complex problems and identifying patterns and trends through analytical thinking and data examination


Communication skills:

  • I can effectively communicate complex ideas and information in both verbal and written forms
  • This was crucial while working on a public health project in a time of a global pandemic


Self organization:

  • High degree of self organization and independence
  • Proven track record of successful remote work


Team player:

  • I enjoy to collaborate with others to achieve a common goal



MiSCELLANEO

Passionate open?source developer:

  • See my GitHub profile @JonasCir for details
  • I am convinced that the open source movement represents the future


Cloud Provider:

  • Familiar with Amazon Web Services (AWS) in a production environment
  • Knowledgeable of Google Cloud due to private usage


Webserver:

  • Familiar with the usage of both, Nginx and Apache2, in production environments
  • Familiar with Let?s Encrypt


Keycloak:

  • Proficient with usage, deployment, and client authorization (OIDC/OAuth2)


REST:

  • Strong familiarity with the design and implementation of secure, authenticated REST APIs


GraphQL:

  • Knowledgeable of GraphQL API design due to private usage


Message queues:

  • Used RabbitMQ together with Celery for internal tooling while working for Flixbus

Betriebssysteme

Linux
Google Fuchsia
Google Android
Windows

Programmiersprachen

Java
Rust
Python
C/C++
x86 assembler
C#

Datenbanken

postgreSQL
MySQL/;ariaDB
Elasticsearch
Fortgeschritten
SQLite
etcd
Redis

Branchen

Branchen

  • Transportation
  • Industrial Machinery Manufacturing
  • Public Health
  • Fuchsia?powered IoT devices

Einsatzorte

Einsatzorte

Mainz (+10km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

3 Monate
2025-01 - heute

Analysis, refinement, and creation of new SOC workfolows

Cybersecurity Consultant SOC
Cybersecurity Consultant SOC
  • This includes the development of standard operating procedures and playbooks
  • Analysis, refinement, and creation of new of company security policies
  • Support SOC operation through best practice and clear process documentation
Liebherr?IT Services GmbH
4 Jahre 6 Monate
2020-10 - heute

SORMAS

Software Engineer Java Python Docker ...
Software Engineer

Kernentwickler von SORMAS, einer open-source e-Health Lösung die sowohl in Gesundheitsämtern als auch international zur COVID-19 Pandemiebekämpfung eingesetzt wird. Hauptaufgaben waren Design und Implementierung von

  • "Sormas2Sormas", welches das einfache Teilen von Falldaten ermöglicht.
  • einem Audit Systems welches sicherheitsrelevante Informationen aufzeichnet.
  • einer Schnittstelle zu einem Fallmelde-Tool.

GitHub Git IntelliJ Atlassian JIRA Atlassian Confluence
Java Python Docker PostgreSQL Keycloak etcd
vitagroup AG
Remote
1 Jahr 9 Monate
2023-04 - 2024-12

Monitoring of security relevants events in SIEM and EDR

SOC Analyst
SOC Analyst
  • Analysis and response to detected security incidents.
  • Optimization of detection processes and implementation of countermeasures.
  • Threat intelligence, threat hunting, and detection engineering.
Liebherr?IT Services GmbH
Remote
2 Jahre
2021-04 - 2023-03

open?source software system to support public health departments

Software Engineer Docker JavaEE etcd ...
Software Engineer
  • SORMAS core?team developer:
    • ?SORMAS is an open?source software system to support public health departments all over the world in their fight against the Covid?19 pandemic and beyond.
  • Main contribution was the design and implementation of:
    • Sormas2Sormas, which enables frictionless sharing of Covid?19 case data between public health offices.
    • An auditing subsystem, which records all relevant system operations and user interactions.
Docker JavaEE etcd Keycloak PostgreSQL
Vitagroup AG
Remote
6 Monate
2020-10 - 2021-03

implementation of an interface to the German case reporting tool

Software Engineer Docker JavaEE Spring Boot ...
Software Engineer
  • SORMAS core?team developer:
    • SORMAS is an open?source software system to support public health departments all over the world in their fight against the Covid?19 pandemic and beyond.
  • Main contribution was to support the implementation of an interface to the German case reporting tool.
Docker JavaEE Spring Boot and PostgreSQL PostgreSQL
IMIS Infektionsübermittlung GbR
Remote
6 Monate
2020-04 - 2020-09

Design and implementation of a SIEM and log collection system

Junior IT?Security Engineer ?
Junior IT?Security Engineer ?
  • Design and implementation of a SIEM and log collection system tailored to the needs of industrial networks based on Elasticsearch
KORAMIS GmbH
Saarbrücken, Germany
2 Jahre
2018-04 - 2020-03

Implementation of automated security solutions

Working Student: IT?Security Engineer
Working Student: IT?Security Engineer
  • Implementation of automated security solutions. Design and implementation of a SIEM system based on Elasticsearch, Logstash, and Kibana (ELK?Stack). Deployment with Terraform and Ansible to AWS.
  • IT?Security maintenance and incident response.
  • Penetration testing of internal and production systems.
  • Development of internal tooling in Python. Deyployment to Kubernetes cluster
FlixBus/FlixMobility GmbH
Remote
1 Monat
2018-04 - 2018-04

Supervision of a workshop series? practical part

Instructor
Instructor
  • Supervision of a workshop series? practical part concerning smartphone usage and cyber security for elderly people.
Verbraucherzentrale Saarland (Consumer advice center)
Saarbrücken, Germany
5 Monate
2017-11 - 2018-03

IT?Administration

Student Assistan
Student Assistan
  • Website/Database administration and IT infrastructure maintenance
Saarland University, Faculty of Philosophy
Saarbrücken, Germany
3 Jahre
2015-04 - 2018-03

Reverse engineering/Security testing of Android apps

Student Assistant - Research
Student Assistant - Research
  • Reverse engineering/Security testing of Android apps to research malicious advertisement libraries.
  • Design and implementation of an Android?specific fuzz testing framework.
  • Prototyping of a privacy analysis tool in C# using MariaDB as persistence.
Saarland University/Center for IT?Security, Privacy, and Accountability (CISPA)
Saarbrücken, Germany
6 Monate
2016-04 - 2016-09

foundation lecture Programming 2

Student Assistant: Tutor Programming Lecture
Student Assistant: Tutor Programming Lecture
Saarland University, Compiler Design Lab
Saarbrücken, Germany

Aus- und Weiterbildung

Aus- und Weiterbildung

2 Jahre 8 Monate
2019-10 - 2022-05

Computer Science

M.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of cybersecurity
  • Advanced courses in mobile, embedded, web, and usable security
  • MASTER THESiS on request
1 Jahr
2018-10 - 2019-09

Entrepreneurial Cybersecurity

M.Eng., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Eng.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on aspects of cybersecurity and computer science in combination with a business start?up project.
6 Monate
2018-04 - 2018-09

Computer Science

M.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
M.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of computer science.
  • Intermediate study to bridge the time till the start of the Entrepreneurial Cybersecurity Master Program
3 Jahre 6 Monate
2014-10 - 2018-03

Cybersecurity

B.Sc., Saarland University, Department of Computer Science, Saarbrücken, Germany
B.Sc.
Saarland University, Department of Computer Science, Saarbrücken, Germany
  • Focus on theoretical and practical aspects of cybersecurity and computer science
  • BACHELOR THESiS on request
7 Jahre 11 Monate
2006-08 - 2014-06

German high?school

diploma (Abitur), Albertus?Magnus?Gymnasium, St. Ingbert, Germany
diploma (Abitur)
Albertus?Magnus?Gymnasium, St. Ingbert, Germany

Advanced classes (Erweiterungskurse): 

  • Mathematics 
  • German

Position

Position

  • SECURiTY ENGiNEER
  • SOFTWARE ENGiNEER

Kompetenzen

Kompetenzen

Top-Skills

IT-Security SIEM Python Rust Docker AWS Agile Softwareentwicklung PostgreSQL Redis DevOps REST Security Konzepte Ansible Terraform

Schwerpunkte

  • Security Engineering:
    • Design and implementation of SIEM systems including log collection, processing, and enrichment.
  • SOC Analyst:
    • Hunting of cyber threats, swift analysis, and effective incident response. SIEM, EDR, and threat intel.
  • Security Enthusiast:
    • Strong focus on system and application security. Special interested in the design of secure software systems.
  • Software Engineering:
    • Implementation of reliable server backends and tooling in Java, Rust, and Python. Worked on a pandemic management system during the Covid?19 global pandemic.
  • Software Architecture:
    • ?Creation of clean and durable architectures, with expertise in evaluating suitable frameworks that align with project goals and requirements.

Produkte / Standards / Erfahrungen / Methoden

GitHub
Experte
Git
Experte
Ansible
Experte
Terraform
Experte
TOOLS/METHODS

DevOps:

  • Docker (?compose) and Kubernetes
  • Ansible 
  • Terraform
  • GitLab
  • Jenkins
  • GitHub 
  • GitHub Actions CI/CD pipeline


Agile:

  • Several years of working experience in agile environments using Scrum
  • Test Driven Development:
    • Knowledgeable of TDD


Office skills:

  • Familiar with all major office suites and applications


SECURiTY

Security generalist:

  • Strong familiarity with security concepts, principles, and best practices
  • Areas of expertise include system, application, and web security


SIEM:

  • Advanced knowledge of use, operation, and maintenance of the Elastic stack, especially in the context of SIEM
  • I designed two SIEM systems so far


Incident Response:

  • Advanced knowledge of incident response processes, MITRE ATT&CK® framework, threat intelligence management, and EDR
  • Hunting of cyber threats, swift analysis, and effective incident response


App reverse engineering:

  • Security analysis of Android apps while working as student assistant


Access control mechanisms:

  • I am strongly familiar with both, theoretical background and technical realization, of OS access control systems
  • Familiar with SELinux/SEAndroid and Fuchsia object capabilities


SOFT SKiLLS

Adaptability:

  • As shown by my track record, I am used to adapt to new sectors, domains, and projects within a short amount of time


Analytical thinking:

  • Skilled in dissecting complex problems and identifying patterns and trends through analytical thinking and data examination


Communication skills:

  • I can effectively communicate complex ideas and information in both verbal and written forms
  • This was crucial while working on a public health project in a time of a global pandemic


Self organization:

  • High degree of self organization and independence
  • Proven track record of successful remote work


Team player:

  • I enjoy to collaborate with others to achieve a common goal



MiSCELLANEO

Passionate open?source developer:

  • See my GitHub profile @JonasCir for details
  • I am convinced that the open source movement represents the future


Cloud Provider:

  • Familiar with Amazon Web Services (AWS) in a production environment
  • Knowledgeable of Google Cloud due to private usage


Webserver:

  • Familiar with the usage of both, Nginx and Apache2, in production environments
  • Familiar with Let?s Encrypt


Keycloak:

  • Proficient with usage, deployment, and client authorization (OIDC/OAuth2)


REST:

  • Strong familiarity with the design and implementation of secure, authenticated REST APIs


GraphQL:

  • Knowledgeable of GraphQL API design due to private usage


Message queues:

  • Used RabbitMQ together with Celery for internal tooling while working for Flixbus

Betriebssysteme

Linux
Google Fuchsia
Google Android
Windows

Programmiersprachen

Java
Rust
Python
C/C++
x86 assembler
C#

Datenbanken

postgreSQL
MySQL/;ariaDB
Elasticsearch
Fortgeschritten
SQLite
etcd
Redis

Branchen

Branchen

  • Transportation
  • Industrial Machinery Manufacturing
  • Public Health
  • Fuchsia?powered IoT devices

Vertrauen Sie auf Randstad

Im Bereich Freelancing
Im Bereich Arbeitnehmerüberlassung / Personalvermittlung

Fragen?

Rufen Sie uns an +49 89 500316-300 oder schreiben Sie uns:

Das Freelancer-Portal

Direktester geht's nicht! Ganz einfach Freelancer finden und direkt Kontakt aufnehmen.