Senior Backend Engineer - Freelance

Who we are: 

We are Boombit, a full-service agency and content studio that empowers companies to grow through strategy, creativity, technology services, and exceptional human talent. Since 2012, we have propelled companies forward by delivering quality, innovation, and purpose-driven work.

Job purpose:

We are seeking a Senior Backend Engineer with strong architecture design skills, deep technical knowledge, and a pragmatic approach to software development. This role is ideal for someone who enjoys crafting scalable, secure backend systems while also contributing to technical strategy and mentoring other engineers.

You will drive the evolution of our backend services using modern frameworks and cloud infrastructure, ensuring reliability, performance, and alignment with long-term business goals.

Job details: 

• Location: 100% remote - open to Colombia based candidates.
• Schedule: Monday to Friday, 8:00 AM - 5:00 PM Costa Rica time zone.
• Work Model: Full-time flexible (freelance based on hours worked / on-demand engagement)
• Language Proficiency: Spanish (Native) / English (C1+ written, spoken, and reading)
• Availability: Immediate availability preferred

Key Responsibilities:

• Architecture & System Design

• • Define and evolve the backend architecture with focus on scalability, fault tolerance, and security.
  • Establish engineering standards, code governance, and technical design patterns (e.g., microservices, hexagonal architecture, DDD).
  • Design event-driven and distributed systems with clear service boundaries and efficient data flow.

• Development & Implementation

• • Build maintainable, reusable, and efficient backend services using modern frameworks such as .NET Core, Node.js, Java, Go, or Python.
  • Design and document RESTful, GraphQL, and gRPC APIs for internal and external integrations.
  • Work closely with DevOps to deploy containerized services (Docker, Kubernetes) and manage CI/CD pipelines (GitHub Actions, Azure DevOps, etc.).

• Performance, Security & Reliability

• • Optimize system performance through profiling, code refactoring, and architectural reviews.
  • Implement monitoring and observability using tools like Prometheus, Grafana, ELK Stack, or Azure Application Insights.
  • Ensure systems meet compliance, security, and privacy requirements (OWASP, ISO, SOC2).

• Collaboration & Mentorship

• • Collaborate with Product, Data, and Frontend teams to translate requirements into scalable solutions.
  • Provide code reviews, technical direction, and mentorship to mid/junior engineers.
  • Foster a culture of continuous improvement, testing, and knowledge sharing.

Required Academic Background:

• Bachelor’s degree in Computer Science, Software Engineering, Systems Engineering, or a closely related technical field.
• Formal training in software architecture, distributed systems, cloud computing, or information security is highly valued.

Required Skills and Experience:

• 7+ years of hands-on experience designing, developing, and optimizing backend systems in high-scale environments.
• Expertise in at least one core programming language used in backend development: .NET Core / C# (preferred), Node.js, Java, Go, or Python. 
• Cloud infrastructure proficiency, especially in Microsoft Azure (preferred), with solid exposure to AWS or GCP for hybrid or multi-cloud setups.

• Relational database expertise including design, normalization, query optimization, and performance tuning with platforms like SQL Server, PostgreSQL, or MySQL.
• Strong background in API design and integration, including RESTful services, GraphQL, and gRPC, following best practices in documentation, security, and versioning.
• Demonstrated experience implementing CI/CD pipelines and managing infrastructure-as-code using Terraform, Bicep, or similar tools in DevOps-oriented environments.
• Strong knowledge of software design patterns, SOLID principles, and microservices architecture. 
• Experience in application security, performance optimization, and monitoring frameworks. 
  
• Preferred Skills:
  • Familiarity with event-driven systems. 
  • Experience integrating with identity and access management solutions.
  • Exposure to serverless computing and domain-driven design (DDD) principles.
  • Prior experience in global delivery or multi-region environments.
    
    
• Excellent communication skills, with the ability to articulate technical concepts clearly to non-technical stakeholders and collaborate effectively across distributed teams.
• Bilingual communication capacity, with native-level Spanish and intermediate English proficiency (C1), ensuring effective collaboration in regional and international production contexts.

Nice to have (Not exclusive)

• Experience working in remote, distributed, or cross-cultural teams, with exposure to agile methodologies (Scrum, Kanban) and asynchronous collaboration tools (Jira, Confluence, Notion).
• Experience with event-driven architectures using tools like Kafka, Azure Event Grid, or RabbitMQ.
• Familiarity with serverless computing models (e.g., Azure Functions, AWS Lambda) and domain-driven design (DDD) principles.
• Prior involvement in multi-region deployments or globally distributed backend systems.

Core Competencies:

At our company, we believe that success is not just about technical proficiency but also how you work with others and approach challenges. As part of our team, you’ll be expected to demonstrate the following key competencies:

• Excellent communication and interpersonal skills: Ability to effectively communicate and collaborate with clients and team members. 
• Problem-solving and critical thinking: Ability to manage complex projects and find solutions to ensure project success. 
• Organizational skills: Strong attention to detail and ability to manage multiple clients and projects simultaneously. 
• Resilience and adaptability: Ability to navigate challenges and adapt to shifting client needs. 
• Proactive and resourceful: Anticipate client needs and take initiative to ensure high-quality service delivery. 
  

How to apply: 

If you’re passionate about designing high-performance backend systems and collaborating across disciplines to solve complex engineering challenges, we’d love to hear from you. To apply, please follow these steps:

• Submit Your CV: Upload an updated and detailed resume highlighting your experience in backend development, system architecture, API design, cloud platforms, and CI/CD practices.