Backend Engineer + Ai

We are looking for a Senior Backend Engineer with strong experience designing, building, and evolving scalable, reliable, and secure backend systems. This is a hands-on engineering role for someone who goes beyond feature implementation. We are looking for an engineer with strong technical judgment who can understand complex systems end-to-end, contribute to architectural decisions, identify and address technical debt, and continuously improve the quality and maintainability of our platform.

AI is becoming a core part of how we build software. We expect engineers to effectively use modern AI-assisted development tools while maintaining strong ownership and engineering judgment over the code and systems they deliver.

Responsibilities

- Design, build, and evolve scalable backend services and APIs, primarily using Node.js, TypeScript, and Express.js.

- Own technical solutions end-to-end, from design and implementation through deployment, observability, and production support.

- Contribute to the evolution of our backend architecture and participate actively in architectural and technical design decisions.

- Identify, prioritize, and address technical debt, balancing long-term maintainability with product delivery.

- Apply solid software design principles and patterns, choosing appropriate solutions based on context and trade-offs rather than applying patterns by default.

- Design clear application boundaries and separation of concerns across services, business logic, and persistence layers.

- Design and optimize PostgreSQL schemas, queries, indexes, migrations, and transactional workflows.

- Build reliable financial workflows with appropriate strategies for idempotency, concurrency, consistency, retries, failure handling, and reconciliation.

- Design and maintain REST APIs and integrations with internal systems and external providers.

- Design asynchronous and event-driven workflows when appropriate.

- Build systems with strong principles around reliability, scalability, resilience, security, and performance.

- Work with AWS infrastructure and cloud services as part of developing and operating production systems.

- Improve production visibility through structured logging, metrics, tracing, monitoring, and alerting.

- Investigate complex production incidents, perform root-cause analysis,



and implement sustainable solutions rather than temporary fixes.

- Maintain high engineering quality through automated testing, code reviews, documentation, and continuous refactoring.

- Use AI-assisted engineering tools to improve development speed, testing, debugging, code review, and engineering productivity while maintaining human ownership of technical decisions.

- Challenge existing technical decisions constructively and help continuously improve our engineering standards.

- Share knowledge and contribute to strengthening the technical capabilities of the engineering team.

- Collaborate closely with Product, QA, Data, Platform, and other engineers to translate business requirements into robust technical solutions.

Requirements

- 8+ years of professional backend engineering experience, with significant experience building and operating production systems.

- Strong hands-on experience with Node.js and TypeScript in production environments.

- Experience with Express.js or comparable backend frameworks.

- Experience with Python and familiarity with backend frameworks such as FastAPI, Django, or similar is highly valued.

- Strong knowledge of software architecture, design principles, and design patterns, including their trade-offs and appropriate use cases.

- Strong understanding of relational databases and PostgreSQL, including data modeling, transactions, indexing, query optimization, migrations, and performance.

- Experience working with ORMs and persistence patterns, understanding both their benefits and limitations.

- Strong understanding of API design, authentication, authorization, versioning, security, and third-party integrations.

- Experience designing systems for failure scenarios, including retries, duplicate events, partial failures, race conditions, and external-service degradation.

- Solid understanding of distributed systems and asynchronous processing.

- Experience with automated testing at different levels, including unit, integration,



and end-to-end testing.

- Production experience with AWS or comparable cloud infrastructure.

- Experience with CI/CD, containers, and modern software delivery practices.

- Strong understanding of observability and production troubleshooting.

- Ability to analyze architectural alternatives, identify trade-offs, and clearly explain technical decisions.

- Strong ownership, problem-solving, and communication skills.

- Ability to work autonomously on complex technical problems while collaborating effectively with the broader team.

Nice to have

- Experience in fintech, payments, lending, banking, or other highly transactional environments.

- Experience building systems where financial correctness and data integrity are critical.

- Experience with event-driven architectures, queues, messaging systems, and asynchronous processing.

- Experience with AWS services such as Lambda, ECS/EKS, SQS, SNS, EventBridge, RDS, S3, and CloudWatch.

- Experience with Infrastructure as Code, such as Terraform or CloudFormation.

- Experience with high-volume transactional systems and distributed architectures.

- Experience implementing idempotency, outbox patterns, concurrency control, reconciliation processes, and fault-tolerant workflows.

- Experience with observability platforms such as Datadog, Sentry, or similar tools.

- Familiarity with DDD, Clean Architecture, Hexagonal Architecture, or similar architectural approaches — with the ability to understand when they are useful and when they add unnecessary complexity.

- Experience using modern AI coding assistants, agents, and AI-native development workflows.

- Familiarity with LLMs, tool calling, MCP, agentic workflows, or AI integrations is a plus, but AI specialization is not required.

What we offer

- The opportunity to work on critical financial products with direct impact on customers and business growth.

- High technical ownership and the opportunity to influence how our backend platform evolves.

- Meaningful architecture, scalability, reliability, and technical-debt challenges.

- An engineering environment where AI is becoming a core part of how we build software.

- A collaborative multidisciplinary team across Engineering, Product, Design, QA, Data, and Platform.

- 100% remote — Argentina or Colombia.

📌 Backend Engineer (Bogotá)
🏢 KiWi
📍 Bogotá