Sr Backend Engineer

Ranger Technical Resources, Inc.; Colombia; On-site; COP 150,000,000 - 230,000,000; Full time

Job summary

Ranger Technical Resources, Inc. is partnering with a fast-growing fintech across Latin America to hire a Senior Backend Engineer who can own complex systems for loans, payments, balances, applications, and external integrations.

You will build with Node.js, TypeScript, and PostgreSQL, contribute to backend architecture, reliability, and production decisions, and help raise engineering depth while staying hands-on with code.

Qualifications

• Bachelor's degree or equivalent experience in CS/engineering.
• 8+ years backend experience with ownership of complex production systems.
• Strong Node.js/TypeScript backend services, APIs, and integrations.
• Advanced PostgreSQL data modeling, transactions, indexing, and optimization.
• Experience with transactional systems, idempotency, and failure recovery.
• Proven influence on architecture, service design, and tradeoffs.
• Experience investigating incidents and improving reliability and observability.
• Experience operating backend apps in AWS or other clouds.

Responsibilities

• Design and build backend services, APIs, integrations, and transactional workflows using Node.js and TypeScript.
• Design PostgreSQL data models, transactions, indexes, queries, and database changes for correctness and performance.
• Protect data integrity through idempotency, concurrency controls, transactions, and failure handling.
• Design external integrations with timeouts, retries, duplicates, and partial failures.
• Influence backend architecture, service boundaries, and the placement of business logic.
• Evaluate technical debt and decide when improvements are necessary.
• Build observability into services via structured logging, metrics, monitoring, and alerts.
• Investigate production incidents, identify root causes, and implement fixes to prevent recurrence.
• Own backend capabilities from design to production improvements.
• Collaborate with Product, Data, Platform, QA, frontend, and full-stack engineers to deliver complete solutions.
• Challenge assumptions and propose better approaches to reduce risk or complexity.
• Improve engineering standards, code quality, testing, and architectural consistency.
• Use AI-assisted development tools while reviewing, testing, and taking responsibility for generated code.

Skills

Node.js

TypeScript

Data Modeling

Transactional Systems

System Design

API Design

Distributed Systems

Idempotency

Concurrency Control

Database Optimization

Query Optimization

Observability

AWS

Express.js

Technical Architecture

AI-Assisted Development

Education

Bachelor's degree in Computer Science, Software Engineering, or related field

Tools

PostgreSQL

Node.js

TypeScript

AWS

Job description

Our partner is a fast-growing fintech company providing consumer lending and point-of-sale financing across Latin America. As the business continues to scale, they are strengthening the technical depth of the engineering organization with a Senior Backend Engineer who can take ownership of complex systems supporting loans, payments, balances, applications, and external financial integrations.

This is a deeply hands-on engineering role for someone who thinks beyond individual features. You will build with Node.js, TypeScript, and PostgreSQL while contributing to backend architecture, database design, system reliability, and production decisions where data correctness and failure handling have direct business consequences.

The ideal engineer brings strong technical judgment, curiosity, and ownership. You understand how systems behave when things go wrong, challenge requirements when there is a better approach, and balance technical improvements against business priorities and delivery risk. You will remain close to the code while helping raise engineering standards and technical depth across the team.

Experience and Education:

• Bachelor's degree in Computer Science, Software Engineering, or a related field, or equivalent professional experience
• 8+ years of backend software engineering experience with meaningful ownership of complex production systems
• Strong production experience building backend services, APIs, integrations, and business logic with Node.js and TypeScript
• Advanced PostgreSQL experience across data modeling, transactions, indexing, concurrency, migrations, and query optimization
• Experience designing transactional systems where data correctness, idempotency, external integrations, and failure recovery are critical
• Proven experience influencing backend architecture, service design, and technical tradeoffs
• Hands-on experience investigating production incidents and improving reliability, observability, and system performance
• Meaningful experience operating backend applications within AWS or another cloud environment

Skills and Strengths:

• Node.js
• TypeScript
• Data Modeling
• Transactional Systems
• System Design
• API Design
• Distributed Systems
• Idempotency
• Concurrency Control
• Database Optimization
• Query Optimization
• Observability
• AWS
• Express.js
• Technical Architecture
• AI-Assisted Development

Primary Job Responsibilities:

• Design and build backend services, APIs, integrations, and transactional workflows using Node.js and TypeScript
• Design PostgreSQL data models, transactions, indexes, queries, and database changes for correctness, performance, and maintainability
• Protect data integrity through idempotency, concurrency controls, transactions, reconciliation, and thoughtful failure handling
• Design external integrations that safely handle timeouts, retries, duplicate requests, partial failures, and inconsistent provider responses
• Influence backend architecture, service boundaries, communication patterns, and the placement of business logic
• Evaluate technical debt and determine when improvement is necessary versus when change would introduce unnecessary risk
• Build observability into backend services through structured logging, metrics, monitoring, and alerting
• Investigate complex production incidents, identify root causes, implement fixes, and improve systems to prevent recurrence
• Own backend capabilities through design, development, testing, deployment, monitoring, and continued production improvement
• Partner with Product, Data, Platform, QA, frontend, and full stack engineers to clarify requirements and deliver complete solutions
• Challenge technical assumptions and propose better approaches when requirements or existing designs introduce unnecessary risk or complexity
• Improve engineering standards, code quality, testing practices, and architectural consistency across the backend
• Use AI-assisted development tools while independently reviewing, testing, understanding, and taking responsibility for generated code