Senior Backend Engineer - .NET & Payments - Remote - Latin America

FullStack; Cuzco; Remote; PEN 306,000 - 442,000; Full time

Job summary

FullStack is seeking a Senior Backend Engineer to join our talent network and work on production-grade reconciliation and transaction-matching systems for U.S. clients.

You will collaborate directly with client teams, designers, and engineers to deliver robust backend services using C# and the .NET framework. You should have 5+ years of professional software development, strong PostgreSQL skills, and experience with React/TypeScript tooling.

Qualifications

• Bachelor's degree in Computer Science or related field.
• Experience with backend systems and database design.
• Ability to work with production AI/LLM features is a plus.

Responsibilities

• Integrate into client teams and collaborate daily with designers and engineers.
• Build backend services using C#/.NET for production reconciliation or transaction-matching systems.
• Design schemas and ensure decimal precision in PostgreSQL; integrate with accounting workflows.

Skills

C# & .NET

PostgreSQL

React

TypeScript

AWS

Azure

Data pipelines

AI/LLM features

Observability (Datadog)

SQL Server

Education

Bachelor's degree in Computer Science or related field

Job description

About FullStack

FullStack is your AI-native engineering partner, built to turn AI capability into certainty. Most companies can demo AI; few can get it to production and prove what it produced. We close that gap with three capabilities, AI built into your products from the start, elite vetted talent who apply it, and transparent execution that shows value every step of the way. With now over 600 customers in North America, FullStack is one integrated partner for all your AI engineering needs. With FullStack, you move forward with confidence.

• Offering life-changing career opportunities to talented software professionals across the Americas.
• Building highly-skilled software development teams for hundreds of the world’s greatest companies.
• Having delivered hundreds of successful custom software solutions, which have positively impacted the lives and careers of millions of users.
• Our 4.1-star rating on GlassDoor.
• Our client Net Promoter Score of 68, twice the industry average.

About FullStack

FullStack is your AI-native engineering partner, built to turn AI capability into certainty. Most companies can demo AI; few can get it to production and prove what it produced. We close that gap with three capabilities, AI built into your products from the start, elite vetted talent who apply it, and transparent execution that shows value every step of the way. With now over 600 customers in North America, FullStack is one integrated partner for all your AI engineering needs. With FullStack, you move forward with confidence.

We’re Most Proud Of

• Offering life-changing career opportunities to talented software professionals across the Americas.
• Building highly-skilled software development teams for hundreds of the world’s greatest companies.
• Having delivered hundreds of successful custom software solutions, which have positively impacted the lives and careers of millions of users.
• Our 4.1-star rating on GlassDoor.
• Our client Net Promoter Score of 68, twice the industry average.

The Opportunity

Join our talent network and connect with U.S. clients for flexible, project-based development work as a Senior Backend Engineer working with .NET and production reconciliation or transaction-matching systems.

• You will integrate directly into our client's team and work alongside their existing designers and engineers on a daily basis.

What We're Looking For

• 5+ years of professional software development experience.
• Advanced English is required.
• Successful completion of a four-year college degree is required.
• Has engineered, deployed, and maintained backend systems using C# and the .NET framework.
• Has designed schemas, handled transactions, and maintained strict decimal precision in PostgreSQL.
• Has working knowledge of double-entry accounting, subledgers and GL integration
• Has built idempotent, re-playable data ingestion pipelines for BAI2, ACH, or other payment rails.
• Has built internal tooling or exception resolution interfaces using React and TypeScript.
• Has deployed services on AWS and integrated them with existing Azure cloud infrastructure.
• Uses AI coding agents daily to accelerate planning, building, and testing of production software.
• Experience shipping production AI/LLM features is a plus.
• Experience with high-volume bill pay, FBO accounts, chargebacks, or DBA-reviewed database workflows is a plus.
• Experience with SQL Server and observability tools like Datadog is a plus.
• Available to work with significant overlap with U.S. Mountain Time business hours.
• Ability to work through new and difficult issues and contribute to libraries as needed.