OpenAPI Experts in Switzerland
matched in minutes with vetted, available freelancersHire experts who design API contracts, generate client and server code, and connect OpenAPI with tools such as Swagger UI, Postman, and CI pipelines. FRATCH matches you precisely with vetted, available freelancers for fast delivery.
Meet FRATCH Experts in Switzerland, who have recently used OpenAPI
Urs S.
Last position:
CargoMonitor App at MSR Electronics GmbH
MVP app for shock logger to monitor and analyze transport data via BLE as a Kotlin Multiplatform solution for Android and iOS.
Christoph P.
Last position:
ICT DevSecOps Engineer & Security Coordinator at Abraxas Informatik AG
- Interface role with the SOC team; improved incident response time by 45% through structured escalation processes and proactive security monitoring.
- Defined technical standards for a multi-tenant enterprise platform (10+ services), resulting in a 30% shorter onboarding time for new clients in the public sector.
- Active knowledge transfer and mentoring of a 6-person team; increased team autonomy and established a sustainable engineering culture.
- Reduced time to market by 50% by optimizing CI/CD pipelines and establishing self-service deployments.
- Stack: GitLab CI/CD, Kubernetes, Nexus, Harbor, ArgoCD, HashiCorp Vault, Grafana, Python, PostgreSQL, Java, Spring Boot, Flyway, Quarkus, JBoss, Loki, Go, Kafka, Kustomize, MongoDB
Robin O.
Last position:
Co-Founder & AI Solutions Architect at airdys
- Product strategy, architecture, and technical co-direction
- AI workshops, client onboarding and go-to-market activities
- Design and implementation of AI architectures (LLMs, RAG, MCP, agents, voice, automation)
- Hands-on development of prototypes and production-ready AI integrations
- Consulting clients on AI adoption, workflows, and integration into existing infrastructure
- Collaboration with co-founders on strategic direction
- Collaboration in sales and customer acquisition
Tools and Technologies: OpenAI, Anthropic, Azure, Vercel AI SDK, RAG (Retrieval-Augmented Generation), MCP (Model Context Protocol), FastAgent, VAPI, n8n, make.com, LibreChat, PostgreSQL, OpenAPI, Next.js, Vercel, Docker
Jack S.
Last position:
Freelance - Fullstack Engineer at SMG Swiss Marketplace Group
- Supported the team in merging two real estate platforms into a unified Vue.js-based solution
- Developed a custom SSR microservice architecture deployed on AWS Lambdas
- Designed and implemented a map drawing feature
- Took ownership of migrating the microservice from Vue 2 to Vue 3
- Built a scalable SSR microservice architecture using AWS Lambda
- Developed and implemented a critical map drawing feature for real estate visualization
- Successfully migrated the microservice from Vue 2 to Vue 3
- Gained deep knowledge of AWS infrastructure, Datadog, Sentry, and Vite
- Technologies: Vue.js, Node.js, Vite, AWS Lambda, Datadog, Sentry, JavaScript
Thomas M.
Last position:
Developer/Analyst at Nvaria GmbH
- Analyzed migration strategies after Camunda 7 was declared end of life with extended support until 2030.
- Evaluated potential migrations to Camunda 8, Flowable, and Operaton.
- Conducted a proof of concept demonstrating that existing projects could be migrated to both Flowable and Operaton.
- BPMN
- DMN
- Confluence
- Flowable
- Operaton
Felix S.
Last position:
Senior iOS Developer at Commerzbank AG
- The comdirect app for iOS offers an intuitive and user-friendly mobile banking app that allows users to manage their banking efficiently and securely.
- Central features: bank transfers, portfolio analysis, personalized financial manager to facilitate daily banking and financial planning.
- Users: over 1 million.
- Written in native Swift using UIKit and SwiftUI.
- App-wide MVVM and Coordinator design pattern.
- Partial reactive programming using Apple’s Combine framework or vendor RxSwift.
- API integrations and data structures with JSON.
- Documented clean code.
- Continuous integration with Git and Jenkins.
- High unit test coverage with XCTest.
- Agile project setup according to Scrum.
Georgios S.
Last position:
Senior Software Engineer at UBS Bank
- Implementations of a code refactoring framework able to refactor thousands of repositories leveraging Generative AI
- Use Python (Django, Flask, FastAPI), Java and Typescript in Azure Cloud (Data Lake, VMs, AI) and GitLab infrastructure
- Mentoring and pair programming
- Obtained Azure AI-900 and AI-102 certifications
Mathias D.
Last position:
Independent contractor at Allianz-Technology
- Developed a massive web application for second pillar retirement insurances (Swiss BVG, Kollektivleben) with over 1000 web pages using an in-house model language and Angular for front-end and back-end
- Fixed bugs in the code generator and enhanced and re-engineered the application
- Built an automated testbed
- Implemented PDF document generation with XML and Thunderhead
- Resolved issues due to the switch to Java 21
- Replaced middleware server for insurance base data (customers, contracts) using Java/Spring, REST, OpenAPI, Docker, Kubernetes, OpenShift, Azure CI/CD pipeline, Jenkins, and GitHub
Ferran S.
Last position:
Senior Software Engineer at Personal time off / Private projects
- Took on and completed private/organizational projects.
- Continued self-training, e.g., in cloud and reactive architectures.
- Focused deepening of knowledge in areas like Kafka and modern Java 17 enterprise architectures.
Christoph J.
Last position:
Project management, Software engineering, Software architect, DevOps at Migros Genossenschafts Bund
- Greenfield project M-Zollmanager: Development of an internal platform to support users in booking requirement areas on line items in assessment notices.
- Greenfield project M-Deliveryplan: Development of an internal platform for planning and tracking deliveries in the international transport sector.
- Created functions to predict the estimated arrival time of container ships and goods from the port of loading to the port of destination, considering potential events.
- Developed the TrackAndTrace add-on for M-Deliveryplan to track and plan goods and containers.
- Built a generic AI chatbot for Migros app infrastructure, including ChatGPT integration and creating AI workflows with N8N.
- Developed AI assistants to automate repetitive tasks, such as creating release notes or processing Jira tasks based on N8N workflows.
- Further development and maintenance of the M-LFS, M-Vehicleaccess and M-Worklog apps.
- Used C#, Angular 18, DevOps practices, N8N, Kubernetes, Docker, Jira, Confluence and Azure.
- Ongoing project with continuous development of platforms and workflows.
Discover over 15,000 top freelancers
Statistics of experts using OpenAPI
Aggregated from the professional profiles of matched freelancers.
Experience
18 years
Position duration
1.2 years
Positions per freelancer
18
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Banking and Finance, Insurance
Certification focus areas
Information Technology, Business Intelligence, Product Development
Bachelor's degree or higher
100%
Master's degree or higher
38%
Doctorate
25%
Certifications per freelancer
2
Most common languages
German, English, Spanish
Speak two or more languages
100%
Based on our profile pool as of 19 Sep 2026.
Daily rate distribution
The chart shows how the daily rates of freelancers in this technology in Switzerland 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 Switzerland using OpenAPI
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 19 Sep 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
OpenAPI experts industry focus
See which industries our matched freelancers work in most often — every figure is calculated live from the freelancers on FRATCH.
- Information Technology (100%)
- Banking and Finance (80%)
- Insurance (60%)
- Energy (50%)
- Media and Entertainment (50%)
- Professional Services (50%)
- Retail (50%)
- Healthcare (40%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
API contracts
OpenAPI is a machine-readable specification for describing HTTP APIs. It defines paths, parameters, request bodies, responses, authentication and reusable schemas in YAML or JSON. Teams use these contracts to align frontend, backend, mobile and external integration work before implementation begins.
From Swagger to OpenAPI
OpenAPI evolved from the Swagger Specification and is now maintained by the OpenAPI Initiative. The format supports REST-style services and works with JSON Schema concepts, making API behavior easier to validate, document and share across technical and business teams.
Ecosystem and tooling
OpenAPI specialists work across the specification and its surrounding toolchain:
- Create and maintain YAML or JSON API definitions
- Generate documentation with Swagger UI or Redoc
- Validate contracts with linters and automated checks
- Generate SDKs, server stubs and test assets
- Connect definitions to Postman, gateways and CI pipelines
Where companies use it
OpenAPI appears in public APIs, partner integrations and internal service landscapes. It supports products in finance, healthcare, manufacturing, retail and public services, including systems that must coordinate cloud services with established enterprise applications. Swiss teams may use it for multilingual, distributed collaboration across local and remote specialists.
When freelance expertise helps
Companies often bring in a freelancer when an API landscape lacks consistent documentation or when a new service must be exposed safely:
- Standardize inconsistent endpoint descriptions
- Define contracts before parallel implementation starts
- Review authentication, errors, pagination and versioning
- Introduce contract testing into delivery workflows
- Prepare API documentation for partners or customers
What strong specialists deliver
Strong OpenAPI professionals understand both the file format and the systems behind it. They model clear resources, predictable error responses and reusable schemas, while checking that the contract matches real behavior. They also communicate well with product, security and engineering teams, explain trade-offs clearly, and leave maintainable definitions that remain useful after the project ends.
Frequently asked questions
Before you brief your next project: the most common questions about OpenAPI.
OpenAPI describes the behavior of an HTTP API in a structured YAML or JSON document. Companies use it to create documentation, validate requests and responses, generate SDKs, support contract testing and coordinate teams building connected services.
OpenAPI is the successor to the Swagger Specification, while Swagger remains the name of a widely used tooling ecosystem. A specialist should know how to work with Swagger UI and related tools without treating the toolset as the specification itself.
OpenAPI commonly describes REST and HTTP endpoints, where clients interact with defined resources and operations. GraphQL uses a query schema, while gRPC uses protocol buffers and generated remote procedure calls; the right choice depends on client needs, transport, governance and existing systems.
A strong OpenAPI freelancer should understand HTTP semantics, REST design, JSON Schema, authentication and API versioning. Useful adjacent skills include Swagger UI, Redoc, Postman, contract testing, CI pipelines and at least one backend or integration stack.
The need depends on the API landscape, not only on the size of the specification. A focused documentation task may need a different profile than a specialist-led redesign involving gateway policies, generated clients, security review and coordination across several teams.
OpenAPI work is often well suited to remote collaboration because contracts, pull requests and review comments are shared digitally. On-site workshops can still help when teams need to resolve domain boundaries or align closely with Swiss stakeholders, and language expectations should be agreed early.
Review whether the OpenAPI document matches live behavior and covers successful, invalid and authenticated requests. Check naming consistency, reusable schemas, clear examples, accurate error responses, validation results and whether another team can use the documentation without private explanations.
Before taking on OpenAPI work, clarify the source of truth, target consumers, existing API conventions and the required tooling. Also confirm ownership of versioning, review steps, generated artifacts, security rules and how contract changes will be tested against running services.
The average hourly rate of freelancers in Switzerland who have used OpenAPI in their recent projects is 106 €, which corresponds to a daily rate of about 846 € based on an 8-hour working day.
Of the freelancers in Switzerland who have used OpenAPI in their recent projects, 100% hold at least a Bachelor's degree, 38% hold at least a Master's degree, and 25% hold a doctorate.
On average, freelancers in Switzerland who have used OpenAPI in their recent projects have 18 years of professional experience, with a single engagement typically lasting around 1.2 years.
The most common languages among freelancers in Switzerland who have used OpenAPI in their recent projects are German (100%), English (100%), and Spanish (40%).
The most common industries among freelancers in Switzerland who have used OpenAPI in their recent projects are Information Technology (100%), Banking and Finance (80%), and Insurance (60%).
The most common business areas among freelancers in Switzerland who have used OpenAPI in their recent projects are Information Technology (100%), Product Development (100%), and Quality Assurance (60%).
Main locations of FRATCH Experts, who have recently used OpenAPI
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.
Zurich Request a free demo
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Philipp Thomaschewski
FRATCH CEO
