Senior Full-Stack Engineer C#

Coderio; Miami (FL); Hybrid; USD 120,000 - 180,000; Full time

Benefits offered by this job

Hybrid collaboration in Miami area

Long-term contract with high impact

Autonomy and technical leadership

Job summary

Coderio is seeking a Senior Full-Stack Engineer for a leading financial institution project in a hybrid Miami Lakes setting. You will design backend services in C#/.NET, deliver end-to-end features including a React portal, and participate in two-week sprints with Agile ceremonies.

You will collaborate with stakeholders, assist in code reviews, and write unit and regression tests, ensuring high-quality software on a complex workflow system.

Qualifications

• 5+ years of hands-on software development in C# / .NET (7+ preferred).
• Applied knowledge of clean architecture: SOLID, SRP, DRY, DDD.
• Proven experience building an application from scratch.
• Working knowledge of React and CSS.
• Experience in Agile / Scrum teams.
• Strong communication and ability to adapt to a corporate environment.
• Hybrid work model from the Miami Lakes, FL office.
• Professional level of English.

Responsibilities

• Design and build backend services in C# / .NET with clean architecture.
• Deliver features end to end: APIs, integrations, approvals, and React portal.
• Work in an Agile team with two-week sprints and ceremonies.
• Answer teammates' technical questions and participate in code reviews.
• Write and maintain unit and regression tests.
• Document decisions and collaborate with business stakeholders and other systems.

Skills

C# / .NET

Clean architecture

React

CSS

Unit testing

Regression testing

Agile / Scrum

Communication

English proficiency

Tools

REST APIs

Mantis

Job description

About Us

Coderio designs and delivers scalable digital solutions for global companies. We combine strong technical expertise with a product mindset to lead complex software initiatives end-to-end. We work with international clients, value autonomy and clear communication, and build long-term partnerships through technical excellence.

More information: http://coderio.com

The Project

We are looking for a Senior Full-Stack Engineer to join a three-person team at a leading financial institution. The project replaces a legacy system of 16 workflows: a web portal where branch users submit requests, and a backend that sends them to other systems, receives responses, updates statuses and manages approvals. Delivery dates are aggressive, so we need someone who can contribute quickly after onboarding.

Responsibilities

• Design and build backend services in C# / .NET, applying clean architecture and engineering best practices.


• Deliver features end to end: APIs, integrations with other systems, approval-workflow logic and the React web portal.


• Work in an Agile team with two-week sprints and the usual ceremonies.


• Answer teammates' technical questions and take part in code reviews.


• Write and maintain unit and regression tests.


• Document technical decisions and collaborate with business stakeholders and teams that own other systems.

Requirements

• 5+ years of hands-on software development experience in C# / .NET (7+ preferred), building applications rather than only maintaining them.


• Applied knowledge of clean architecture: SOLID principles, separation of concerns (SRP), DRY and domain-driven design.


• Proven experience building an application from scratch.


• Working knowledge of React and CSS (no UI design specialization required).


• Experience writing unit and regression tests.


• Experience working in Agile / Scrum teams.


• Strong in-person communication, teamwork and the ability to adapt to a corporate environment.


• Ability to work in a hybrid model from the Miami Lakes, FL office.


• Professional level of English [confirm with the client].

Nice to Have

• Experience in banking or financial services.


• Experience integrating systems through REST APIs and messaging.


• Experience with workflow and approval processes.


• Familiarity with UI templates such as Mantis.


• A genuine passion for programming and for tackling a challenging, high-volume project.

Benefits

• Hybrid collaboration in a dynamic and fast-paced environment in the Miami / Fort Lauderdale area.


• Long-term contract engagement with high impact and autonomy.


• Strategic and high-visibility role within a modern engineering culture.


• Opportunity to influence technical strategy, especially regarding modern event-driven architectures and AI integrations.


• Collaborative international team with strong technical leadership.

Why Join Coderio?

At Coderio, we value talent and excellence. While we are primarily a remote-first company, this specific strategic role offers the opportunity to work directly on-site to drive high-stakes initiatives. We are passionate about technology, collaboration, and fair compensation. We offer an inclusive and challenging environment with real growth opportunities. If you are motivated to design solutions that make a difference, we are waiting for you.