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Brazil Portugal

  • Design, enhance, and maintain enterprise-grade .NET applications supporting critical business operations.
  • Modernise legacy systems by working across C#, .NET Framework, WinForms, WebForms, and VB.NET codebases.
  • Integrate REST APIs, SOAP services, and XML while collaborating with an Agile, international engineering team.

C# .NET Framework REST APIs SOAP

18 jobs similar to Senior .NET Legacy Modernisation

Jobs ranked by similarity.

Portugal Brazil

  • Design, develop, and enhance enterprise-grade .NET applications, focusing on legacy modernization.
  • Work with existing WinForms, WebForms, and integrate using REST APIs, SOAP, and XML.
  • Collaborate within an agile team to troubleshoot complex issues and contribute to technical decisions.

TXP is a technology consultancy specializing in application modernization and enterprise .NET development. The company fosters a collegial culture where responsibility and authority are shared equally among colleagues, with no mention of employee count.

Brazil

  • Act as a key player in the support and evolution of applications developed in SQL Server and C# .NET, contributing to innovative solutions.
  • Continuously improve processes and engineering practices, mentoring junior developers and promoting a learning environment.
  • Perform a fundamental role in architecture and development, ensuring high performance and scalability in implemented solutions.

CI&T helps large enterprises transform the potential of AI into real business impact with AI Deployment, AI-native execution, and tech-integrated business solutions. With 8,000 employees across 25 countries, they foster a collaborative and innovative culture.

Latin America

  • Design, build, and deliver high-quality, scalable enterprise SaaS applications using C#, .NET Core, and SQL Server.
  • Take end-to-end responsibility for code quality and testing in a Shift Left, AI-assisted development environment.
  • Partner with Product Managers and cross-functional squads to translate business requirements into customer-centric features.

Truelogic is a leading provider of nearshore staff augmentation services headquartered in New York. With over 600 skilled tech professionals based in Latin America, they drive digital disruption by partnering with U.S. companies on impactful projects.

$2,400–$3,700/mo
LATAM Africa Eastern Europe

  • Build and evolve the platform by delivering high-quality customer-facing features.
  • Maintain and extend .NET/C# legacy systems while improving system reliability.
  • Contribute to system design and architecture with a focus on scalability and maintainability.

Scale Army Careers is a recruitment platform that connects software engineers with remote contract opportunities. They are a growing organization focused on quality and efficiency.

LATAM

  • Develop and maintain full-stack features using C#, .NET, Angular, TypeScript, HTML, and CSS in a Shift Left engineering environment.
  • Take full ownership of unit, integration, and performance testing, and leverage AI-powered tools like GitHub Copilot and Claude to accelerate development.
  • Collaborate closely with Product Owners and engineering teammates in an Agile SCRUM environment to build scalable cloud-based SaaS solutions.

Ubiminds is a GPTW-certified, people-first company that partners with American software product companies to scale their global teams. They connect top LATAM talent with international product companies and provide full employer-of-record support and long-term career development.

Serbia

  • Participate in design and development of business applications and customizations using .NET, C#, and MS SQL Server.
  • Research and prototype new ERP modules, optimize code, and support existing functionality.
  • Collaborate with development partners on architecture and code reviews while guiding other developers.

Acumatica is a leading innovator in cloud ERP solutions for small and midsized businesses, offering industry-specific applications that manage risk and drive growth. The company was acquired by Vista Equity Partners in 2025 and maintains a collaborative, high-energy culture that values work/life balance and freakishly friendly customer service.

Brazil

  • Design, develop, and maintain scalable applications using Angular and .NET Core.
  • Build REST APIs, work with microservices, and apply domain-driven design.
  • Collaborate with multidisciplinary teams to ensure high-quality delivery and technical improvements.

Our partner is a company in the financial technology sector, developing scalable digital solutions with a focus on innovation and quality. The team is collaborative, innovation-driven, and values continuous learning in an agile environment.

Brazil

  • Participate in full-cycle design, development, and release of software to build and enhance systems and applications.
  • Collaborate with team members across projects to support departmental and organizational roadmaps.
  • Apply programming standards and techniques to ensure efficient program logic and data manipulation.

Language Services Associates (LSA) provides premier language-based services including translation, interpretation, and cultural communication solutions. With over 240 employees and a network of more than 3,000 global linguists, LSA serves over 2,000 clients worldwide in over 230 languages.

$120,000–$160,000/yr
US

  • Design and deliver REST APIs, domain logic, and background workflows for ERP product areas.
  • Own complex capabilities from technical discovery through implementation and production support.
  • Collaborate with platform, frontend, product, and design teams to turn government workflows into reliable software.

They are an established software company transforming a broad portfolio of Windows-based applications into a modern SaaS suite for county and city governments. They have a lean, collaborative engineering team with decades of domain knowledge.

Brazil

  • Design, develop, and maintain scalable, secure, and high-performance SaaS applications.
  • Investigate and resolve compliance, security, and application quality issues identified through AI-driven analysis.
  • Collaborate with international teams to drive technical decisions and implement solutions.

The partner company is a global SaaS provider seeking a Principal Full Stack Engineer. The team is remote-first and values engineering excellence, AI-powered development, and secure software practices.

Eastern Europe

  • Design, develop, and maintain enterprise applications using ASP.NET, .NET Core, and SQL Server.
  • Build and integrate RESTful APIs, deploy on AWS, and use AI-assisted development tools like GitHub Copilot.
  • Provide L3 support, mentor junior developers, and participate in Agile/Scrum ceremonies.

We are a digital product engineering company that builds products, services, and experiences at scale across all devices and mediums. With 18,000+ experts across 39 countries, our work culture is dynamic and non-hierarchical.

Brazil

  • Develop and maintain SharePoint-based solutions and full stack applications using .NET and Microsoft technologies.
  • Create and administer SharePoint sites, lists, libraries, and permissions while customizing SPFx components.
  • Collaborate with technical teams to troubleshoot issues and improve application performance.

This company specializes in building collaborative platforms and optimizing digital workflows using Microsoft technologies. Their technology-driven team emphasizes innovation, learning, and professional growth.

LATAM

  • Design and develop scalable SaaS applications using C#, .NET, and Angular 16+.
  • Build backend services with Entity Framework and optimize SQL queries.
  • Collaborate with cross-functional teams and use AI-assisted development tools.

Ubiminds is a GPTW-certified, people-first company that connects top LATAM talent with international product companies. They provide full employer-of-record support and long-term career development for their team.

Latin America

  • Remediate security vulnerabilities across the full stack including dependency upgrades, code-level fixes, credential rotation, and container hardening.
  • Write unit and functional tests for every fix to prove vulnerabilities are addressed and features continue to work.
  • Own major version upgrades end to end, diagnosing and resolving build breaks or behavior changes through completion.

Truelogic is a leading provider of nearshore staff augmentation services headquartered in New York, delivering technology solutions to companies of all sizes. With a team of over 600 skilled tech professionals based in Latin America, they partner with US companies to drive digital transformation.

Latin America

  • Lead architectural direction and technical governance for enterprise-grade backend services.
  • Build and maintain high-performance RESTful APIs and microservices using C# and .NET 6+.
  • Collaborate with US-based stakeholders to translate business requirements into modern technical solutions.

CodeRoad provides end-to-end software development services, helping businesses scale with ideal infrastructure solutions. They offer nearshore technology services to empower businesses in an evolving digital landscape.

India

  • Develop and maintain enterprise web applications using ASP.NET MVC and Web API.
  • Build and optimize SQL Server databases, stored procedures, and queries.
  • Collaborate with cross-functional teams and use AI-assisted development tools.

Jobgether is an AI-powered job matching platform that connects candidates with employers. It partners with companies to manage hiring processes using technology.

Europe

  • Design and develop enterprise services and custom applications that support business-critical processes across ERP, WMS and other enterprise platforms.
  • Transform business requirements into scalable technical solutions, working closely with Product Owners, Architects and stakeholders across Logistics, Finance, Pharma & Quality and Supply Chain.
  • Develop and optimise system integrations and APIs, ensuring reliable communication, interoperability and high-quality data exchange between enterprise applications.

Redcare Pharmacy is Europe's leading e-pharmacy, providing pharmaceutical services online. The company fosters a healthy, collaborative work environment where every employee feels valued and inspired.

US Unlimited PTO

  • Build and evolve AidenBot, the core automation engine for Windows endpoint management.
  • Design, implement, and maintain production software in C# and .NET with focus on reliability.
  • Collaborate on technical architecture and deliver end-to-end product capabilities.

Aiden provides a Windows endpoint management platform that automates IT operations. It is a hyper-growth startup with a culture focused on openness, honesty, and transparency where everyone has an equal voice.