Senior .NET Engineer — Colombia

About NextLink Labs

NextLink Labs is a fast growing technology firm focused on helping companies build, scale, and secure their software applications and organizations. We believe that in order for companies, teams, and products to succeed, technology must be utilized effectively and securely. We pride ourselves in helping our clients win in their respective industries.

As a remote-first company with team members spread out all across the country, NextLink Labs continuously works to ensure our work environment is comfortable and collaborative. We also aim to maintain an inclusive work environment where everyone can thrive professionally and live full lives outside of work.

Position Summary

NextLink Labs is seeking a motivated Senior .NET Developer with a strong background in C# and ASP.NET Core to join our Custom Software Development consulting team. A successful person in this role will be tasked with building and maintaining scalable backend services and APIs for our clients and will be able to seamlessly integrate with our clients engineering teams.

Key Responsibilities

As a Senior .NET Developer, you will design and implement robust backend systems and RESTful APIs while making critical architecture decisions to rapidly deliver features for an enterprise application built on Clean Architecture and CQRS patterns. If you are a self-motivated engineer looking to take ownership of your work, we invite you to join our team at NextLink Labs.

What You'll Do

• Design, develop, and maintain scalable backend services and APIs using C# and ASP.NET Core (.NET 9)

• Implement and extend Clean Architecture with CQRS patterns using MediatR

• Work with other engineers to architect and implement modular, well-structured solutions

• Communicate directly with clients to give demonstrations and receive feedback

• Build and optimize data access layers using Dapper and PostgreSQL

• Implement request validation pipelines using FluentValidation

• Work in an agile team environment with daily stand ups, and weekly agile meetings

• Engage in code reviews of your teammates' work

• Contribute to observability and monitoring using Serilog, OpenTelemetry, and Grafana

Required Qualifications

• 5+ years of experience building backend services with C# and .NET (ASP.NET Core)

• Strong understanding of Clean Architecture, CQRS, and the Mediator pattern (MediatR)

• Experience designing and implementing RESTful APIs with OpenAPI/Swagger documentation

• Proficiency with relational databases (PostgreSQL) and lightweight ORMs (Dapper)

• Experience with validation frameworks such as FluentValidation

• Ability to work independently and take ownership in a variety of software engagements

• Ability to scope individual features and full software projects based on client requests

• Excellent written, verbal, and interpersonal skills with the ability to build buy-in, facilitate compromise, and guide client expectations

• Strong unit-testing abilities using xUnit, Moq, and FluentAssertions

• Proficient understanding of version control systems (Git)

• Understanding of security best practices including JWT-based authentication and authorization

• Understanding of fundamental design principles behind scalable and distributed systems

• Strong problem-solving, analytical, and strategic thinking abilities, capable of making well-informed and timely decisions

Nice to Have

• Experienced with DevOps tooling (Docker, Kubernetes, Azure Pipelines, Azure Container Registry)

• Experience with frontend frameworks, specifically ReactJS

• Familiarity with one other backend language, such as Golang, Ruby on Rails, or Python

Why NextLink Labs

• We’re a technical consulting firm that values clarity, ownership, and outcomes

• Competitive salary with bonus structure

• Remote-first culture, flexible work schedule, and autonomy to do your best work

• Responsibility and autonomy at a growing company

• The opportunity to build something big and exciting

Visa Sponsorship

• At this time, we are unable to provide visa sponsorship or take over sponsorship for existing visas. Candidates must be authorized to work in the Colombia without the need for current or future sponsorship.