Mainframe Experts in Düsseldorf
matched in minutes from over 15,000 CVs with vetted, available specialistsHire experts who keep COBOL, JCL, CICS, Db2 for z/OS and batch processing running with care. They support migrations, incident fixes and long-lived core systems, with fast, precise matching to vetted, available freelancers.
Meet FRATCH Experts in Düsseldorf, who have recently used Mainframe
Christian Wonneberger
Last position:
Software Engineer, cross-platform Application Manager at International major bank
- Creating interfaces between the legacy platform and the new container solution
- Coordinating required contributions from line units
- Moderating regular status meetings with the software vendor
- Minimally invasive conversion of TWS scheduling from the old to the new platform
- Environment: IBM Mainframe, DB2, CICS, MQ, Red Hat Linux, Oracle, Kubernetes, Kafka, Helm, GitLab, Jenkins
Hans-Dieter Große-Kreul
Last position:
Training as an AI Expert
I continuously expand my expertise in AI and automation, working with ChatGPT, OpenAI, Manus, Gemini, MS CoPilot, API, LangChain, Hugging Face, Manus, TensorFlow and Auto-GPT as well as Python-based ML frameworks and MLOps tools to intelligently transform classic software development, analysis, and testing processes.
Thorsten Otremba
Last position:
Workstream Lead (WS) at Bank-Verlag GmbH
- Introduction of giro card with Visa Debit card payment function (Combocard) for Commerzbank
- Support for the Card Processing Team (card processing; Clearing & Settlement incl. Dispute Management teams) in project work
- Creation of requirements for the Clearing & Settlement team, Authorization team (AZ) and Card Production team (KP) as part of a requirements catalog
- Requirements engineering (requirements management) with business contact person
- Participation in workstream meetings between VISA Inc., SRC Security Research & Consulting GmbH, Commerzbank AG and consulting firms (PwC and Senacor Technologies AG)
- Sprint planning with Jira tickets of type Task and use of Confluence
- Creation and presentation of weekly status reports for the Clearing & Settlement, Dispute Management and Reporting & GUI workstreams
- Coordination with network and file transfer teams for connection tests of new interfaces, e.g. setup of host keys, use of VPN or sipnet connections
- Coordination of the delivery of test files, e.g. exchange rates (FX rates; TC 56 of VISA rates), VISA Debit and Credit transactions (format Base II) and EANSS/ISS Base II clearing files to the Debit Clearing System (DCS)
- Conducting coordination meetings on the use of Visanet Settlement Service (VSS) and PSD2 reports and payment traffic statistics (ZVS)
- Organizing workshops with FiServ (First Data) on Dispute Management and complaint handling
- Setup and maintenance of Open Point List (OPL) in Confluence
- Technologies/methods: Jira, Confluence, giro card, VISA Debit card, payments, Kanban board, BIN, routing, CIQ, VPAY, ScalaTest, Dispute Management
Jürgen Schoemaker
Last position:
IT Consultant / Analyst / Developer / Tester / Support at Automotive Manufacturer
- Analysis, software development/customization, and testing of various transaction and batch objects
- Conducting functional integration and regression tests on TEST and QA platforms under z/OS for later production implementation
- Hardware / Software / Tools: IBM MVS, z/OS, JES2/3, TSO-ISPF, JCL, DB2, SQL, SQL/PL, QMF, QMF for Workstations, SPUFI, FileAid, IMS-DB/DC, MFS, XPEDITER, COBOL, REXX, Windows 10, MS Office 365, MS Teams, batch job management via OPC, BETA92, RVS, BVB, ABL, DIALOGplus, PROBA, PRODPR (VW internal systems), JIRA, CONFLUENCE
Esmail Saberi
Last position:
Senior Load and Performance Tester at Deutsche Bahn (DB-Netz)
- Design, development, and execution of load and performance tests for the PRISMA project
- Use of Apache Jmeter, Gatling, Apache ActiveMQ, Jms/Tibco Ems, SikuliX, Jython, Amazon AWS, PAN-Client
- Methods: load tests, test automation
Dalia Cananau
Last position:
Oracle Developer at Freelance
- Design and implementation of an OCI-based data warehouse and ETL system to replace legacy mainframe applications
- Developed a database optimization strategy and planned the rapid conversion of JCL and COBOL routines to PL/SQL using AI
- Developed an Oracle Apex-based app for internal administrative processes in the public sector (office equipment, staff training)
- Implemented PL/SQL workflows for approval processes and created a responsive mobile version with JavaScript and CSS
- Used Azure DevOps for backlog management and documentation, and Git for version control
- Developed REST interfaces to CRM systems
- Replaced and reprogrammed Oracle Forms screens with Oracle Apex and updated to the latest Apex versions
- Designed a Git branching strategy and conducted code reviews
- Maintained and further developed an EDI-based data exchange system based on Oracle Advanced Queuing for the public sector in Austria
- Performed data analysis and created charts in the Oracle Apex frontend; installed standalone ORDS and Apex 23.1
- Worked agile using the Spotify model; developed complex Apex pages with support from Oracle JET
- Rebuilt and customized existing PL/SQL packages, created workarounds for database version differences, and optimized queries
- Developed Apex applications for broker pools to manage and optimize Oracle databases in the banking environment, including SSO-based authorization systems with OAuth2 and Keycloak
- Built extensive Oracle Apex applications for BI and data mining modernization projects and developed manual and automated projection methods in the frontend
- Carried out data warehousing projects in the banking sector and used Scrum and Kanban in team projects
Bernhard Döpper
Last position:
Enterprise Architect. And responsible for the cross-functional architecture as well as all domains with a focus on the sales at Süddeutsche Krankenversicherung
Creation of business and technical concepts as well as support for enterprise architecture management as part of the migration to the Adesso standard insurance solutions and the renewal of surrounding systems
Interface definitions
Business analysis and creation of the business concepts for input management and sales
Creation of architecture guidelines and processes
Processing technical and business decisions in the architecture board
Definition of service processes and system management aspects
Creation of the technical target operating model
Creation of an integration architecture for AI/LLMs from the providers Commasoft and Insiders
CommaSoft (Alan) webpages and web services
Insiders for Smartfix based on web services
Creation of a question catalog for a security/regulatory check.
Analysis of threats using threat modeling / STRIDE incl. creation of a set of measures to secure the systems
System environment: Jira, Confluence, Java, Enterprise Architect, VAIT/DORA, KritisV, GDPR, IT ServiceMgmt, Adesso Ecosphere and Insure Health, DoPIX and successor product, SmartFix, SmartFlow, Zabas, Kolumbus, Clarc archive, BiPRO, AI / LLM, MS Azure, AWS, TOM/FMO
Rüdiger Kohl
Last position:
Data Analyst and Reporting Manager at Energieversroger
Implemented Power BI reporting for various departments at an energy provider. Agile project: responsible for organizing and coordinating with departments and IT, and regularly presented interim steps and results to project management.
Discover over 15,000 top freelancers
Statistics of experts using Mainframe
Aggregated from the professional profiles of matched freelancers.
Experience
33 years (Germany: 29 years)
Position duration
1.9 years (Germany: 2.3 years)
Positions per freelancer
22 (Germany: 17)
Top business areas
Information Technology, Business Intelligence, Operations
Top industries
Information Technology, Banking and Finance, Insurance
Certification focus areas
Information Technology, Human Resources, Project Management
Bachelor's degree or higher
83% (Germany: 72%)
Master's degree or higher
50% (Germany: 43%)
Doctorate
17% (Germany: 12%)
Certifications per freelancer
1 (Germany: 3)
Most common languages
German, English, Spanish
Speak two or more languages
88% (Germany: 96%)
Based on our profile pool as of 30 Aug 2026.
Daily rate distribution
The chart shows how the daily rates of freelancers in this technology in Düsseldorf are distributed, based on recent contracts on our platform. Each bar covers a rate range — its height shows how many freelancers charge within that range.
Average rates of experts in Düsseldorf using Mainframe
Rates are based on recent contracts and do not include FRATCH margin.
The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.
The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.
Calculated based on our freelancers’ daily rates as of 30 Aug 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
About the technology
Core systems
Mainframe systems run the business logic behind payments, policy handling, claims, ledger processing and other high-volume back-office work. They are built for stability, throughput and controlled change. Many companies still rely on IBM Z and z/OS for their most critical workloads.
Typical work
- COBOL and PL/I application changes
- JCL and batch job maintenance
- CICS, IMS and Db2 for z/OS support
- Integration with APIs, files and middleware
- Modernization without disrupting operations
Ecosystem
The mainframe ecosystem includes z/OS, TSO/ISPF, RACF, DFSORT, CICS, IMS, Db2, Endevor and other change-control tools. Strong specialists know how these parts connect and where a small mistake can affect production. They also understand release windows, testing constraints and access control.
When to bring in help
Companies usually need freelance expertise when a core application is hard to change, documentation is thin or a delivery date is near. Common triggers are production incidents, audit findings, batch failures, interface changes and migration planning. Düsseldorf teams often look for experts who can work with local stakeholders and support German-language documentation.
What good specialists do
A strong professional reads legacy code quickly, traces data across jobs and transactions, and keeps focus on risk. They write clean changes, explain impact clearly and test with discipline. Knowledge of COBOL, JCL, SQL, CICS and operations is often more useful than broad generalization.
Modernization path
Mainframe work is not only maintenance. It often includes API enablement, data extraction, workload tuning, security hardening and stepwise migration to surrounding systems. The best experts know when to keep logic on IBM Z and when to decouple it safely.
Frequently asked questions
Need clarity? These are the questions we hear most often about Mainframe.
Mainframe systems are still used for core transaction processing, batch workloads, account handling, claims, billing and other high-trust operations. They are common in industries where availability, data integrity and controlled change matter more than trend-driven tooling. Many teams still run these workloads on IBM Z with z/OS.
Mainframe is the broader term for the class of enterprise computers and the workloads that run on them. IBM Z is a well-known mainframe family, while z/OS is the operating system many teams work with on that hardware. People also search for MVS or IBM mainframe when they mean older or legacy environments.
A strong Mainframe specialist usually brings COBOL, JCL, CICS, Db2 for z/OS and batch troubleshooting. Useful adjacent skills include file handling, RACF security, ISPF, sync points, and reading production logs. Experience with change control and testing in regulated systems also matters.
Mainframe projects often need help as soon as the work touches production logic, interfaces or batch chains that are hard to observe. If the team lacks documentation, has a shrinking internal skill base or faces a migration deadline, an external specialist can reduce risk quickly. The earlier the involvement, the easier the handover.
Yes, much of Mainframe work can be done remotely if access, approvals and security setup are in place. On-site time can still help during incidents, workshops or when teams need close coordination with operations and business owners in Düsseldorf. The best setup depends on access rules and the criticality of the system.
A Mainframe specialist may know COBOL, but the role is broader than code changes alone. Good work often spans JCL, batch flows, CICS or IMS, Db2, security and operational control. If the task is only a code edit, COBOL alone may be enough; for production systems, broader mainframe knowledge is safer.
Look for clear explanations of dependencies, batch steps, test approach and rollback risk. A strong Mainframe expert can trace a problem across jobs, programs and data sets without guesswork and can describe what will happen in production. Practical examples from similar IBM Z or z/OS work are more useful than vague claims.
Mainframe is often weighed against distributed systems, cloud platforms or incremental application replacement. Those options can work well for new services, but they do not automatically replace the stability and control of existing core workloads. The right choice depends on risk, data complexity and the cost of change.
The average hourly rate of freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects is 105 €, which corresponds to a daily rate of about 843 € based on an 8-hour working day.
Of the freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects, 83% hold at least a Bachelor's degree, 50% hold at least a Master's degree, and 17% hold a doctorate.
On average, freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects have 33 years of professional experience, with a single engagement typically lasting around 1.9 years.
The most common languages among freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects are German (100%), English (88%), and Spanish (25%).
The most common industries among freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects are Information Technology (100%), Banking and Finance (88%), and Insurance (63%).
The most common business areas among freelancers in Dusseldorf, Germany who have used Mainframe in their recent projects are Information Technology (100%), Business Intelligence (75%), and Operations (63%).
Main locations of FRATCH Experts, who have recently used Mainframe
Our freelancers and interim experts are at home across the DACH region — available on-site in the major business hubs or fully remote. Choose a location to discover matched specialists, local market insights and up-to-date availability.
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Munich 
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Philipp Thomaschewski
FRATCH CEO
