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Fusion Practices

Senior C#/.NET Developer

On site

London, United kingdom

Senior

Freelance

06-01-2026

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Skills

Communication Leadership C# SQL CI/CD DevOps Problem-solving Decision-making Architecture Databases git Asp.Net SQL Server Agile .NET CI/CD Pipelines Microservices

Job Specifications

Overview
We are seeking a Senior C#/.NET Developer to design, build, and lead the development of high-quality, scalable software solutions. This role combines hands-on engineering, technical leadership, and mentorship, playing a key role in architecture decisions and delivery excellence-particularly for systems that handle large, complex data sets and high-volume processing.
Key Responsibilities
Lead the design and development of applications using C#, .NET (.NET Core/.NET 6+)
Design and optimize solutions that process and manage large-scale data sets with a focus on performance and scalability
Define and enforce coding standards, architecture patterns, and best practices
Architect scalable, secure, and maintainable solutions (monoliths or microservices) capable of handling high data throughput and concurrency
Perform code reviews and mentor junior and mid-level developers
Collaborate with product managers, architects, QA, and DevOps teams
Translate business requirements into technical designs and implementation plans
Optimize application performance, reliability, and security, including query optimization, data access patterns, and caching strategies
Drive technical decision-making and resolve complex engineering challenges
Support CI/CD pipelines and deployment strategies
Required Skills & Qualifications
7+ years of professional experience with C# and .NET
Strong experience with ASP.NET, Web APIs, RESTful services
Solid understanding of object-oriented design, SOLID principles, and design patterns
Strong experience working with large data sets, high-volume transactions, and performance-critical systems
Experience with Entity Framework and relational databases (SQL Server preferred), including database design and query optimization for large-scale data
Proven leadership experience in a senior or lead developer role
Strong problem-solving and communication skills
Experience with source control (Git) and agile development practices

About the Company

At Fusion Practices, we specialise in delivering data driven projects and finance transformations. Being Oracle and Microsoft partners, we have been delivering solutions that combine both Azure Data, Oracle Fusion Cloud and PAAS. Fusion Practices can assist you in: Delivering data driven projects on Oracle and Azure Moving on premise systems to Azure or Oracle Cloud Target state architecture and roadmap IFRS17 Implementation and business process automation Automating your manual finance and insurance processes Fusion Pr... Know more