REST API Experts in Vienna
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Meet FRATCH Experts in Vienna, who have recently used REST API
Chrisabel Prischl
Last position:
AI Systems & Product Strategy Expert at Webmeisterin
I build. I advise. I think in systems. After years leading digital transformation at scale — Accenture, BP, Lidl — I made a deliberate choice: trade platform dependency for structural independence. My focus is at the intersection of AI systems, product strategy, and venture thinking. I work with operators and founders who want to move fast without losing control — of their data, their stack, their direction.
Michael Langer
Last position:
IAM Developer & IT Architect at Internationale Bank
Design and implementation of new functionalities in the areas of Lifecycle Management (LCM), Role Management (RLM) and Access Governance
Adjustment of the company-wide Segregation of Duties (SoD) matrix to ensure regulatory and internal compliance requirements
Further development and configuration of recertification processes
Creation and adaptation of custom workflows, rules and tasks in SailPoint IdentityIQ (BeanShell, XML, Java)
Use of static code analysis with SonarQube to ensure code quality and compliance with defined development standards
Regular code reviews within the development team to ensure quality, share knowledge and follow clean code principles
Work in an agile Scrum team with daily communication, sprint planning and reviews
Coordination with testers, test managers and business departments to ensure quality and smooth production rollout
Active involvement in release planning and deployment coordination, including test preparation, cutover activities and rollback strategies
Analysis and sustainable resolution of issues in the IAM production environment (2nd- and 3rd-level support)
Reproduction of complex errors, identification of root causes and implementation of lasting fixes
Creation of technical analyses and recommendations for operations and further development
Marcel Steger
Last position:
Senior AI Engineer - Python at Insurance Company
Project Tech Stack: Python, AWS, Azure, FastAPI, openai, pandas, unittest/pymock
Achievements:
- Engineered automated data extraction pipelines to transform complex Excel datasets into structured formats via LLM-driven workflows.
- Architected a generative slide-deck engine that translates natural language prompts into formatted presentation assets.
- Integrated advanced LLM capabilities with the OpenAI Response API, implementing sophisticated tool-calling and structured output logic.
- Developed and containerized scalable backend microservice using FastAPI, Docker, and OpenShift to host and serve agentic skills.
Jori Martini
Last position:
Agile IT Manager Healthcare Systems at MA01 Gov. Digital City
- Responsible for managing GMP-critical systems
- Leading a team of 20 professionals
- Vendor management with a €15M annual budget
Michail Matjuchin
Last position:
OpenShift Specialist, Developer at Insurance
Project goal: Introduce OpenShift as the run-time platform and migrate all applications to OpenShift.
My contribution: Make sure logging and monitoring for the applications were in place. Set up and put into operation the OpenShift components for logging and monitoring (Elasticsearch, Prometheus, and Grafana). Develop and implement the security concept for OpenShift. Work with developers to define and carry out the application changes needed for the OpenShift migration. Integrate monitoring into the applications.
Technical environment: Java, WebSphere Liberty, OpenShift components, Elasticsearch (ELK stack), Prometheus, Grafana.
Markus Kleiber
Last position:
Document Development at Insurance Company
- Replacement of original Dopix documents and modules into the Quadient document environment
- Extension of document logic
Joseph Wagner
Last position:
Freelancer Cloud / Solution Architect (AWS) at A1 Bank
- I am responsible for providing solution architecture and technical assistance for a migration initiative aimed at transitioning to a new core banking system.
- The project involves replacing in-house development with a commercially available off-the-shelf core banking system operated as SaaS on AWS.
- Duties encompass solution design, technical coordination, supporting development teams, and providing IT support and troubleshooting.
- Managing over 10 global vendors and partners is crucial to project success.
- Technologies: VMWare ESXi, AWS, EKS Kubernetes, Mastercard Payment Transaction Service, Avaloq, A1 Telekom Austria infrastructure, CheckPoint FW, F5, Site-to-Site VPNs, PingID, Futurae SDK, Airlock, UC4/Automic, Firebase, iOS/Android lifecycle management, AWS IAM, AWS AppStream, AWS S3, AWS Transfer Family, QlikView, OpenAPI.
Michael Polivanov
Last position:
Strategy Consultant & Program Architect at Hypo Tirol Bank AG
- Portfolio Analysis & Migration Roadmap: Conducted structured analysis and risk classification of the HCL Notes infrastructure, created a prioritized migration portfolio with effort estimates as a key decision basis for management.
- Target Architecture & Modernization Concept: Developed the architecture strategy for retiring legacy applications, defined requirements for a centralized business process engine to reduce OPEX and licensing costs in the long term.
- Program Governance & Setup: Established roadmap and backlog structures as well as central project documentation (MS SharePoint), set up stakeholder management for the Notes decommissioning program.
Vladislav Filipic
Last position:
Senior Test Automation Engineer / Test Manager at Stadt Wien – WUKSEA
- Creating test scenarios, manual test cases and test data using boundary value analysis and equivalence classes
- Executing functional and non-functional tests (manually with Postman and web application, automated with WebDriver, JUnit and NUnit)
- Setting up, automating and maintaining the test automation framework with Java, Spring Boot, Selenium and Cucumber in IntelliJ (system, regression, smoke, UI and integration tests for web front-end and SOAP API backend interfaces)
- Automating backend NUnit test cases in Visual Studio
- Test management: developing and implementing test strategy and test plans, controlling tests, quality ownership and prioritizing risk-based tests, as well as maintaining documentation in Confluence
- Detailed analysis and quality assurance of requirements
- Creating and maintaining Jenkins pipelines, ensuring quality in build & deployment
- Close collaboration with business analysts, developers, testers and test management
- Identifying, creating and tracking defects/bugs, with thorough test documentation
- Reporting test results and defect reports
- Monitoring test processes and continuous improvements
- Reviewing test data and test results in PostgreSQL database via pgAdmin
- Supporting effort estimation and backlog prioritization
- Analyzing and debugging development code System environment: Java, JUnit, Spring Boot, Selenium, Cucumber, JavaScript, Jenkins, C#, NUnit, Postman, Bitbucket, Confluence, Jira, xRay, pgAdmin, PostgreSQL, SonarQube, Maven, IntelliJ, Visual Studio, CI/CD, SOAP API interfaces
Maximilian Götz-Mikus
Last position:
Solo Developer / Founder at InvAPI
- Privacy-first, stateless e-invoice API providing AI-powered extraction, bidirectional format conversion (UBL/CII/ZUGFeRD), batch processing, and validation for German/Austrian e-invoice compliance
- Technologies: Nuxt 4, Vue 3, Nitro, TypeScript, Cloudflare (D1, R2), Stripe, OAuth, AI/LLM integration
Attila Danics
Last position:
Full-Stack Software Engineer at Research Data Evaluation
- Custom anonymized research data analyzer, providing insights and facilitating data-driven decision-making.
- Designed and developed back- and frontend.
- Delivered end-to-end solution.
- Accelerated research timeline by 2 months.
Nedim Kupusovic
Last position:
Manual Tester and Test Automation Engineer at IT-Systemhaus der Bundesagentur für Arbeit
- Design appropriate test cases to verify the GUI in Azure Test Plans
- Creation and execution of manual test cases
- Test design for user stories to be implemented in the current sprint
- Analysis of deviations/bugs based on log files and Kibana dashboards
- Creation of bug tickets with error description, screenshots, and short videos
- Prioritization of open bug tickets together with the PO
- Retest of bugs and hotfixes
- Execution of manual tests to ensure a 100% fulfillment rate of all functional requirements
- Selection, installation, and maintenance of a test automation tool (Selenium)
- Implementation of automated regression tests
- Continuous expansion of the object repository and adaptation of automated test cases (acceptance, integration, and system tests)
- Creation of test logs before each sprint change
Damian Gueorguiev
Last position:
Senior Test Manager Release Management at SVS
- Proof of Concept Test Management Tool
- Test strategy
- Test concepts
- Management of requirements
- JIRA
- Zephyr
- Confluence
- MS Word
- MS Project
- MS Excel
- Tosca
Andrea Giugliano
Last position:
Organizational and process consulting · Agile coach for two complex teams at Public sector
Completed project assignment · 12/2025 – 06/2026
- Current state & interviews: Analysis of team structure, roles, responsibilities, dependencies, knowledge distribution, seniority, and agile maturity through one-on-one, team, and stakeholder interviews.
- Team diagnosis & risks: Structured assessment of skill level, ownership, willingness to learn, collaboration, communication, and team fit; analysis of knowledge concentration, risks for operations, team, and product, as well as external perception with root causes and improvement suggestions.
- Target-state options & impact analysis: Development of structural options and assessment of their effects on collaboration, delivery speed, responsibilities, quality, and knowledge distribution.
- Organizational design & alignment: Introduction of measures to distribute knowledge and responsibility, improve collaboration with departments and external teams, define the stakeholder communication framework, and provide recommendations for involvement in the technology relaunch.
- Management decision basis: Documentation of implemented measures and their effects; option catalog with risks, consequences, and scenarios for team and product, plus a final overall recommendation. The scoped analysis and optimization assignment was successfully completed at the end of June 2026.
Current tasks
- Scrum Master / Agile Coach for two complex teams: Further development of agile collaboration and self-organization, facilitation of Scrum events, and impediment management.
- Delivery & team development: Improvement of requirements and refinement processes, clarification of roles, responsibilities, and workflows, as well as further development of the team and knowledge distribution.
- Cross-functional alignment: Coordination between development, Product Owner, Requirements Engineering, UX/UI, architecture, and stakeholders.
- Cross-area analysis: Examination of communication paths, process deviations, dependencies, processing times, and status transparency, with derivation of concrete improvement measures.
Aaron Heimel
Last position:
Career Break
- Big move, focus on DIY hobbies, small personal software projects.
Discover over 15,000 top freelancers
Statistics of experts using REST API
Aggregated from the professional profiles of matched freelancers.
Experience
20 years
Position duration
1.7 years
Positions per freelancer
11
Top business areas
Information Technology, Product Development, Project Management
Top industries
Information Technology, Government and Administration, Banking and Finance
Certification focus areas
Information Technology, Project Management, Product Development
Bachelor's degree or higher
79%
Master's degree or higher
57%
Certifications per freelancer
3
Most common languages
German, English, Italian
Speak two or more languages
100%
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 Vienna 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 Vienna using REST API
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
REST basics
REST API work centers on predictable HTTP endpoints, resource-based URLs, and clear request and response formats. It is used to expose data and actions for web apps, mobile apps, partner systems, and internal services.
Common use cases
- Public APIs for products and integrations
- Internal service-to-service communication
- Data access for web and mobile front ends
- Partner onboarding and third-party connections
Skills that matter
Strong professionals know HTTP methods, status codes, caching, pagination, auth, and versioning. They also write clear API contracts, handle errors consistently, and keep responses stable for clients that depend on them.
Tooling and ecosystem
REST API work often sits beside OpenAPI, Swagger, Postman, JSON, and OAuth 2.0. In modern stacks, specialists also coordinate with gateways, reverse proxies, monitoring tools, and backend frameworks that publish or consume endpoints.
When to bring in freelancers
Companies look for freelance expertise when an API needs to be designed, repaired, documented, or aligned across teams. This is common during product launches, refactors, migrations, and integrations with external systems, including projects in Vienna where teams need clear remote collaboration and concise English documentation.
What strong experts deliver
- Consistent endpoint design and naming
- Reliable auth, validation, and error handling
- OpenAPI specs and usable documentation
- Safe changes without breaking clients
Strong REST API specialists think in contracts, not just code. They keep the API simple for consumers, stable over time, and easy to test, support, and extend.
Frequently asked questions
Quick answers to the questions that come up most around REST API.
A strong REST API is used to expose application data and actions through standard HTTP requests. Companies rely on it for web apps, mobile apps, partner integrations, and internal service communication. It works well when many clients need the same backend in a clear, predictable way.
REST API design is usually simpler to understand and easier to cache, document, and debug than GraphQL or gRPC. GraphQL is often chosen when clients need flexible queries, while gRPC fits tightly controlled service-to-service traffic. Many teams still prefer REST for public interfaces and broad compatibility.
A capable REST API specialist should also know HTTP, JSON, authentication, OpenAPI, and basic backend security. Depending on the project, experience with OAuth 2.0, API gateways, testing tools, and one or more backend stacks is important. Clean documentation is a practical bonus, not an afterthought.
The right level depends on how sensitive the interface is. A small internal endpoint set may only need a REST API specialist who can implement and document it cleanly, while public or business-critical interfaces need someone who has handled versioning, backward compatibility, and failure handling before. The key is proven API design, not a job title.
Most REST API work can be done remotely because the core tasks are design, documentation, testing, and integration support. On-site time in Vienna can help when many stakeholders need quick decisions, especially early in a project or during a migration. Many teams use a mixed setup and keep communication in English unless local coordination calls for German.
Look for clear endpoint structure, consistent status codes, thoughtful error responses, and documentation that matches the implementation. A strong REST API professional also protects existing clients during changes and explains trade-offs clearly. If they can talk through versioning, auth, and testing without hand-waving, that is a good sign.
Yes, REST API is still a strong default for many new systems because it is widely understood and easy to integrate. It is especially practical when you need public access, partner integrations, or simple consumption from different client types. The best choice still depends on the needs of the product, not on trends.
A well-run REST API engagement usually includes endpoint design, implementation support, documentation, test cases, and guidance on versioning and error handling. For larger work, you may also want an OpenAPI specification, sample requests, and support during rollout. Those deliverables make the API easier to use and maintain.
The average hourly rate of freelancers in Vienna, Austria who have used REST API in their recent projects is 92 €, which corresponds to a daily rate of about 738 € based on an 8-hour working day.
Of the freelancers in Vienna, Austria who have used REST API in their recent projects, 79% hold at least a Bachelor's degree and 57% hold at least a Master's degree.
On average, freelancers in Vienna, Austria who have used REST API in their recent projects have 20 years of professional experience, with a single engagement typically lasting around 1.7 years.
The most common languages among freelancers in Vienna, Austria who have used REST API in their recent projects are German (100%), English (100%), and Italian (19%).
The most common industries among freelancers in Vienna, Austria who have used REST API in their recent projects are Information Technology (94%), Government and Administration (69%), and Banking and Finance (63%).
The most common business areas among freelancers in Vienna, Austria who have used REST API in their recent projects are Information Technology (100%), Product Development (88%), and Project Management (63%).
Main locations of FRATCH Experts, who have recently used REST API
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.
Countries:
Vienna 
Graz Request a free demo
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Philipp Thomaschewski
FRATCH CEO
