ASP.NET Web API Experts in Germany
in minutes from 15,000 CVs with the power of AIHire experts who build REST APIs, secure .NET service layers, and integrate ASP.NET Web API with SQL Server, Azure, and front-end systems. Get fast, precise matching with vetted, available freelancers.
Meet FRATCH Experts in Germany, who have recently used ASP.NET Web API
Matthias Spiller
Last position:
Software Developer and Consultant at CLADE GmbH
- Analysis of the existing CAN communication between microcontrollers
- Analysis of the sensors used and the measured values collected
- Planning the CAN messages for transmitting the measured values
- Iterative adjustment of the microcontroller code to the new CAN messages
- Cross-compilation from x64 to arm64
Oliver Fries
Last position:
Modernization of a multi-company backend system at Energy utility company
Enhancement and modernization of a mature Aspire backend application in the environment of a utility company, focusing on new business requirements, testing, legacy code cleanup, and stable backend delivery.
Core contributions & results Implemented new business requirements in the context of customer orders, subcontractors, and cross-company backend processes, and ensured consistent workflows in a distributed system landscape. Modernized existing backend components step by step and reduced technical debt through targeted legacy code cleanup, refactoring, and structured code reviews. Improved the testability of business-critical services by expanding automated tests with xUnit, AutoFixture, and clearer validation structures. Supported the further development of workflow automations and integration processes via microservices, messaging, and API-based communication. Took over source code from external firms, systematically checked code quality, and derived technical improvements for maintainability, stability, and integration. Worked in agile development processes with Jira, Confluence, and Azure DevOps and supported cross-team alignment on architecture, quality, and implementation. Technical metrics Technologies & methods C#, .NET, ASP.NET, ASP.NET Core, Aspire, Docker, RabbitMQ, gRPC, REST API, Swagger, Microservices, NServiceBus, AutoMapper, Autofac, xUnit, AutoFixture, FluentValidation, Entity Framework Core, MediatR, Redis, Consul, Serilog, SonarQube, Azure DevOps, Azure Monitor, GitLab, Google Protocol Buffers, IronPDF, Mailjet, Jira, Confluence, Miro, agile development, Scrum, code reviews, refactoring, legacy code cleanup, workflow automation, power grids
Kiriakos Krastillis
Last position:
Tech Lead / Architect : OTTO API Platform at OTTO
maturing their API Practices on both, a Business and Technology level. My role encompasses strategy, architecture, developer advocacy as well as hands on software engineering, enabling both technical teams and business leadership to adopt and act on API- centric principles effectively. Coincidentally, we also establish GitOps, DX and Platform Best practices with this project.
Highlights:
- Aligning executives with the initiative by clarifying strategy, replacing misconceptions and myths with facts, clarifying the value of existing assets and enabling informed decision-making
- Formulating a way forward for API Lifecycle Management at OTTO
- Driving platform progress and fostering developer engagement by hands-on engineering work towards strategic goals
API Lifecycle Management, Team Topologies, Organizational Evolution, Regulatory, Platform Advocate, Developer Platform, Communities of Practice, Terraform, Kotlin, Kafka, Kong, WSO2, Apigee, Gravitee, Backstage, AsyncAPI, OpenAPI, API Design, AWS, react, nodejs, typescript, redocly, reactive programming, CDC, golang, gingonic, GitOps, DX (developer experience), stakeholder management, roadmaps, workshops, discovery.
Chisom N.
Last position:
Founder & Analytics Engineer at Museni Nexus
- Client — Podimo ApS (podcast & audiobook streaming): build the finance reporting layer on BigQuery + dbt + Airflow, including the core revenue-transaction fact tables used across finance reporting.
- API automation: design and build a BigQuery → Airflow → Microsoft Dynamics 365 Business Central REST-API pipeline to automate sales-invoice posting, with idempotency and master-data sync between systems.
- Delivery: sole engineer on the engagement — requirements, modelling, orchestration and stakeholder communication with the client finance team, end to end.
Saqib Javed
Last position:
AI Developer / AI Engineer (Lead) at KOM4TEC GmbH
- Conceptual design and implementation of modular AI assistants for sales and business processes in the Microsoft ecosystem (Agentic AI, Copilot extensions)
- Frontend architecture and development with React + TypeScript for embedded chat and assistant surfaces (streaming UI, hooks, React Query, OpenAPI clients)
- Enterprise-level agent development: reusable skill/agent library, MCP server, review and compliance gates
- LLM integration into the user experience: Anthropic (Claude), OpenAI, tool use, RAG pipelines, prompt engineering, guardrails
- Architecture and code review consulting as well as mentoring in the AI development team
- Integration with Microsoft Graph, Power Platform, and Azure services
- Technologies: React, TypeScript, Anthropic Claude, OpenAI, MCP, RAG, Microsoft Graph, Power Platform, Azure
Manuel Kübler
Last position:
.NET Developer, SAP Business One Consultant at Own Projects
- DTO class generator: In-house development of a tool for the automatic generation of classes, functions, and methods for use in .NET Core projects based on SAP Business One Service Layer metadata
- E-invoice import add-on: Development of a SAP Business One add-on / coresuite module for the automated import of ZUGFeRD e-invoices as incoming invoices – with configurable mapping to flexibly control the import logic across four mapping types (DIRECT, SQL, FIXED, EXPR). The add-on is available as a licensed product for SAP Business One customers.
Stack: SAP Business One, SAP Business One Service Layer, coresuite Country Package, C#
Benjamin Matschke
Last position:
Founder, system architect, and main developer at Institute for Artificial Study (IAS)
- Expert-supervised AI systems for scientific reasoning, model evaluation, and research workflows.
- Built the IAS Problem Solver, an orchestrated system for difficult mathematical reasoning; it achieved 84% in one submitted answer set on the Leipzig mathematics benchmark.
- Built a resumable state-machine pipeline for research-grade mathematics benchmark generation: source selection, LLM-agent-based phenomenon discovery, task synthesis, gold-answer and certificate generation and validation, probing, repair, human feedback, and quality gates, targeting tasks that are difficult, natural, verifiable, and cost-effective.
- Current work extends this into budget-aware AI research workflows for real scientific problems with expert review.
Tech stack: Python, OpenAI/OpenRouter-compatible APIs, embeddings, RAG, SQLite.
Thomas Hoefkens
Last position:
Senior MLOps, DevOps Engineer at Trianel Energy
- Build and operate an end-to-end MLOps platform on Azure ML and Kubernetes (Kubeflow) for the automated deployment, monitoring, and scaling of forecasting models (including Temporal Fusion Transformer, Informer, Autoformer).
- Implement CI/CD pipelines in Azure DevOps for the full ML lifecycle – from resource provisioning (Terraform), data transformation (Hugging Face Datasets, Pandas, PyTorch, CUDA cluster) through training and evaluation to model registry and endpoint deployment.
- Integrate MLflow for experiment tracking, model versioning, performance monitoring, and automated registration in the Azure Model Registry.
- Develop and containerize PyTorch training jobs (Azure Notebook, Jupyter Notebooks) for price and time series forecasting (PFC models) with automatic rollout via Azure ML Endpoints and REST/gRPC interfaces, Docker containerization, secured with OAuth 2.0.
- Set up monitoring and alerting mechanisms (Prometheus, MLflow Metrics), log centralization, and cost monitoring.
- Automate infrastructure provisioning and model deployment using Terraform, Helm, and Azure CLI; connect to existing market data systems and event pipelines.
- Migrate existing workloads and databases (IONOS → Azure, MongoDB) with integration into central MLOps workflows and internal networks.
- Extend the platform with LLM-based tools (LangChain, LangServe) to integrate GPT-based analysis modules into existing Spring Boot services for market anomaly detection and automated reports.
- Analyze and architect a software solution to process large volumes of data efficiently (>3000 messages/sec.) (market data store).
- Spring Boot / Java 21 container development with RabbitMQ for distributing stock market data via MongoDB (Kubernetes) with fast storage of data in Redis RMaps, deduplication, forwarding messages to Read Model queues, and building Read Models for UI display in MongoDB.
- Integration of RESTHeart to create a REST API for MongoDB.
- Build an Angular frontend to simplify data queries and master data maintenance.
- Agentic coding with remote and local LLMs (Claude Sonnet, Ollama Qwen) and MCP servers.
- Develop Python scripts for transforming and cleaning incoming stock market data (Pandas, scikit-learn).
Thorsten Lenzen
Last position:
Senior Security Analyst
- Analysis and remediation of security vulnerabilities in a risk assessment system for energy trading
- System analysis
- Threat modeling
- Decision-making on vulnerability mitigation strategies
- Implementation of vulnerability detection mechanisms
- Security scans
- DevSecOps practices
- Technical environment: Visual Studio Code, JetBrains Suite, MS Threat Modeling Tool, DevSecOps, Git, AWS, DynamoDB, SQL Server, Endur, Snowflake, Orca
- Languages: C#, JavaScript, TypeScript, Python, PowerShell, Bash, Terraform, SQL
Rizwan Bashir
Last position:
Software Developer/Database/DevOps at Sutor Bank
- Migration and maintenance of a legacy system to the latest version of .NET for the asset management system
- Design and implementation of tests
- Creation of deployment pipelines and documentation
- Further development and implementation of change requests
- Technologies: C#, ASP.NET, Unit of Work, IOC, Three tier architecture, Entity Framework Core, DB First, Web API, Swagger, Open API, Monolith, Python, Oracle, Azure DevOps, GIT, xUnit, NSubstitute
- Methods: Agile development using Scrum
Abdelkader Elachouri
Last position:
.Net Developer
Development of a voucher management portal
Management of vouchers
Redeeming vouchers
Implementation of the frontend
Implementation of Web API and backend libraries for communication with the database
Creation of database stored procedures, functions, and views
Further development of the company portal
.Net Core 3 / 7 / C#
ASP.Net Core Web API
Visual Studio / MS SQL Server / Azure DevOps / git repository
Moritz Freyburger
Last position:
AWS Developer/DevOps Engineer (Energy Trading) at RWE Supply & Trading GmbH
- Further development and partial new development of a distributed cloud application for providing data in energy trading
- Independent implementation of the infrastructure (IaC)
- Creation of automated CI/CD pipelines, containers, REST APIs, and Lambdas
- Continuous cost and performance optimization
- Collaboration in an international Scrum team and with experts in energy trading
- Technologies: C#/ASP.NET Core; EF Core; PostgreSQL; Terraform/AWS CloudFormation; HTTP; REST/Web API; Swagger/OpenAPI; Azure DevOps; Rider; VS Code; git; Docker; AWS (S3, EC2, Fargate, Lambda, Step Functions, Secrets Manager, VPCs, ALB/NLB, RDS, Cloudwatch, AWS CLI, Amazon MQ); Redis; OAuth; OpenID Connect
- Languages: C#; TypeScript; HCL; Docker; Bash; PowerShell; YML; JSON
Michael Salzig
Last position:
Senior Software / Full-Stack Developer at DOUGLAS INFORMATIK & SERVICE GmbH
- data integration for SAP marketing applications Emarsys and SMC
- processing data from SAP applications for email delivery
- event-driven architecture with around 50 microservices for processing several million messages per day during high season
- development of a marketing campaign management tool (frontend Angular, backend C# ASP Web API)
- support for the Product Owner in communication with stakeholders and creation of epics, stories, and tasks
Gavrilo Olah
Last position:
Head of Software Development at Davidsmeyer & Paul GmbH
- Strategic project development, realisation, and implementation with internal and/or external development team
- Multi stakeholder management
- Planning new projects, cost calculation, risk calculation
- AI project for the electrical components production
- Building management systems integrations (BACnet, Modbus, etc)
- Inhouse BACring system architecture and development (control system for fire protection and smoke extraction systems)
- Inhouse MES system architecture and development
- Project management
- Agile-SCRUM project development
- Solution architecture and processes analytics (UML)
- Business application development
- Jira project management
- Reporting and documentation
- Recruitment process for the IT staff
- Software architecture, project development, costs, risks
- Education IT staff (internal and external)
- Responsibility for 5 development/DevOps/QA teams
Yannide Djache Ngangoum
Last position:
Development Engineer Test Automation at Vorwerk Elektrowerke GmbH & Co. KG
- Project: Thermomix Online Mock
- Manual execution of functional tests
- Implementation of automated end-to-end tests
- Execution of regression tests and analysis of results
- Further development of the QA website on the server using Express.js, Handlebars, and Node.js
- Further development of the test environment
- Technologies: Agile software development Scrum, Robot Framework, Python, JavaScript, Git (GitLab), VS Code, Jira, Confluence, Express.js, Handlebars, Phoenix/Elixir
Discover over 15,000 top freelancers
Statistics of experts using ASP.NET Web API
Aggregated from the professional profiles of matched freelancers.
Experience
22 years
Position duration
3.1 years
Positions per freelancer
14
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Manufacturing, Banking and Finance
Certification focus areas
Information Technology, Product Development, Project Management
Bachelor's degree or higher
83%
Master's degree or higher
44%
Doctorate
5%
Certifications per freelancer
2
Most common languages
German, English, French
Speak two or more languages
98%
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 Germany 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 Germany using ASP.NET Web 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
API delivery
ASP.NET Web API is used to build HTTP services in the .NET stack. It fits product back ends, mobile app back ends, partner integrations, and public endpoints that expose business data in a clean, predictable way. Teams also use it for migration work from older ASP.NET services.
What specialists do
Strong professionals shape routing, controllers, request validation, authentication, and versioning. They design response models, error handling, and serialization so the API stays stable as features grow.
Common stack
- ASP.NET Web API and ASP.NET Core Web API
- C# and the .NET runtime
- Entity Framework and SQL Server
- OAuth, JWT, and OpenAPI documentation
- Azure hosting, logging, and monitoring
When companies bring help
Companies usually bring in freelance expertise when an API needs to be launched quickly, refactored safely, or connected to several systems. In Germany, this often happens in enterprise IT, manufacturing, logistics, finance, and SaaS teams that need reliable service contracts and clear handover.
What good work looks like
- Consistent endpoint design and naming
- Clear separation between API, domain, and data access
- Correct status codes and useful error messages
- Authentication and authorization that fit the product
- Tests that cover critical flows and edge cases
Related skills
ASP.NET Web API work often overlaps with REST, JSON, OpenAPI, Azure, SQL Server, and front-end integration. Many projects also need migration support from WCF or older ASP.NET MVC code, plus careful coordination with security and operations teams.
Frequently asked questions
Everything clients usually want to know about ASP.NET Web API, in one place.
ASP.NET Web API is used to expose business logic over HTTP through REST-style endpoints. Companies rely on it for web back ends, mobile back ends, partner integrations, and service layers that need to serve JSON cleanly. It is a strong fit when a .NET system must be consumed by several clients.
ASP.NET Web API refers to the classic API stack that was part of the older ASP.NET platform. ASP.NET Core Web API is the newer option and is the usual choice for new work on modern .NET. Many companies still need specialists who can maintain legacy APIs or migrate them safely.
A strong ASP.NET Web API specialist should also be comfortable with C#, REST, JSON, authentication, and data access. In practice, that often includes SQL Server, Entity Framework, OpenAPI, and Azure. Good communication matters too, because API work touches front-end, product, and operations teams.
ASP.NET Web API expertise is worth bringing in when the API has security concerns, multiple consumers, tight delivery dates, or a risky legacy base. It also helps when a team needs a clean redesign of endpoints, versioning, or test coverage. For simple CRUD work, an internal specialist may be enough.
Yes, ASP.NET Web API work is often remote because the deliverables are code, tests, and documentation. For Germany-based teams, remote collaboration works well when requirements are clear and the specialist can join planning and review sessions. On-site time may help during migration or stakeholder-heavy projects.
Look for a ASP.NET Web API specialist who has shipped APIs with stable contracts, sensible error handling, and clear versioning. Review code samples for structure, tests, and how they handle authentication and validation. Strong professionals also explain trade-offs in plain language.
ASP.NET Web API is built for HTTP services, so it gives teams a clear way to design endpoints, return structured data, and integrate with web and mobile clients. That makes it a better fit than a generic back end when the main job is to provide a dependable API contract. It is especially useful in .NET-heavy environments.
A capable ASP.NET Web API freelancer should deliver working endpoints, tests, documentation, and deployment notes. Depending on the project, that may also include authentication setup, OpenAPI docs, logging, and migration support from older services. Good handover is part of the job, not an extra.
The average hourly rate of freelancers in Germany who have used ASP.NET Web API in their recent projects is 92 €, which corresponds to a daily rate of about 737 € based on an 8-hour working day.
Of the freelancers in Germany who have used ASP.NET Web API in their recent projects, 83% hold at least a Bachelor's degree, 44% hold at least a Master's degree, and 5% hold a doctorate.
On average, freelancers in Germany who have used ASP.NET Web API in their recent projects have 22 years of professional experience, with a single engagement typically lasting around 3.1 years.
The most common languages among freelancers in Germany who have used ASP.NET Web API in their recent projects are German (98%), English (98%), and French (18%).
The most common industries among freelancers in Germany who have used ASP.NET Web API in their recent projects are Information Technology (98%), Manufacturing (57%), and Banking and Finance (46%).
The most common business areas among freelancers in Germany who have used ASP.NET Web API in their recent projects are Information Technology (98%), Product Development (96%), and Quality Assurance (55%).
Main locations of FRATCH Experts, who have recently used ASP.NET Web 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.
Berlin Hamburg Munich Cologne Frankfurt Stuttgart Dusseldorf Leipzig Dortmund Essen Bremen Dresden Hanover Nuremberg Request a free demo
Get in touch with the FRATCH team and we will get back to you within 4 hours.
Would you rather directly get in touch?
We always have the time for a call or email!
Philipp Thomaschewski
FRATCH CEO
