Backend Engineer (Mid-Level) - NodeJS

Liminal

Location: Portugal, Brazil
Job Type: full-time
Salary: 48,000 - 55,000 EUR
Posted: July 2, 2025

Job Description

Liminal is a global market intelligence and strategic advisory firm specializing in digital identity, financial crime and compliance, and IT security technology solutions across industries while also catering to the private equity and venture capital community. Founded in 2016, Liminal offers strategic and analytical services supporting executive decision-making at all product and business lifecycle stages. We advise some of the world’s most prominent business leaders, investors, and policymakers on building, acquiring, and investing in the next generation of solutions and technologies. We provide access to proprietary data and analysis, strategic frameworks, and integrated insights on the industry’s only market intelligence platform.

Every major company in the world has started focusing on the next generation of digital identity technologies as a necessity for continued growth and security. Our team works with a myriad of organizations, from Fortune 100s to startups, across industries including financial services, technology, telecommunications, and the P2P economy. At Liminal, we help businesses build solutions, execute strategies, invest intelligently, and connect with key decision-makers. We know that it’s in the sharing of discovery and insights that groundwork is laid, problems are solved, and entire sectors advance at the speed of light. Keeping information to ourselves delays progress for all. At Liminal, we don't just respond to the market; we define it.

About the role

We are seeking a dedicated and experienced Backend Engineer to join our team and contribute to the development and scaling of our backend systems. In this role, you will collaborate with cross-functional teams to build, optimize, and maintain backend architectures that power our platform. Your expertise in modern database systems, cloud platforms, and backend services will be essential to delivering high-quality, reliable, and scalable solutions.

What you'll do

Backend Development

Design, implement, and maintain scalable backend systems using modern tools and frameworks like NodeJS
Develop high-performance database systems, with a focus on MongoDB and Google Cloud Platform technologies.
Build and optimize APIs to ensure seamless data flow between systems.

System Architecture

Contribute to the design and development of robust backend architectures that support complex data processing and low-volume, high-availability requirements.
Implement best practices in Identity and Access Management to secure backend systems and data.

Performance Optimization

Identify and implement performance optimizations across backend systems to improve reliability and speed.
Monitor, debug, and resolve system bottlenecks and inefficiencies.

Quality Assurance and Testing

Ensure the reliability of backend systems through comprehensive testing and continuous integration practices.
Write clean, maintainable, and well-documented code.

Collaboration and Growth

Work closely with product managers, front-end developers, and designers to ensure backend systems align with product requirements.
Research and implement new technologies to enhance scalability, security, and performance.

Qualifications

Education & Experience

Bachelor’s degree in Computer Science, Software Engineering, or a related field.
4+ years of experience in backend development with NodeJS, preferably in cloud-based environments.

Technical Skills

Proficiency in designing and developing backend systems using MongoDB and cloud platforms like GCP or AWS.
Experience with content schemas (structured, semi-structured, unstructured) and database performance tuning.
Familiarity with Identity and Access Management principles to secure systems.
Understanding of containerization (Docker), CI/CD pipelines, and microservices architecture.

Soft Skills

Strong problem-solving skills and attention to detail.
Excellent communication skills for effective collaboration with cross-functional teams.
Results-driven mindset with a focus on delivering reliable and scalable solutions.

Preferred Qualifications

Experience with Kubernetes or similar container orchestration platforms.
Knowledge of serverless computing and cloud-native architectures.
A proactive approach to challenges and a passion for continuous learning and innovation.

The pay range for this role is:

48,000 - 55,000 EUR per year (Remote (Lisboa, PT))

48,000 - 55,000 EUR per year (Remote (Porto, PT))

339,757 - 401,531 BRL per year (Remote (Brazil))

🎯 Who is this job for?

This position is ideal for a Mid-Level Backend Engineer with 4+ years of experience in Node.js, MongoDB, and cloud platforms like GCP or AWS. Candidates should be skilled in designing scalable backend systems, API development, and performance optimization. Familiarity with containerization, CI/CD, IAM principles, and microservices architecture is essential.

💬 Potential Interview Questions

What are the benefits of using Node.js for backend development in cloud environments?
Node.js is non-blocking and event-driven, making it ideal for I/O-heavy and scalable applications, especially in cloud environments where efficiency and concurrency matter.
How do you structure a RESTful API using Node.js and Express?
Organize routes, controllers, and services separately; use middleware for validation and authentication; and follow standard REST conventions for endpoint design.
What optimizations can be made to improve MongoDB performance?
Use proper indexing, avoid large document sizes, use aggregation pipelines efficiently, and monitor query performance with tools like MongoDB Atlas or explain().
How do you ensure scalability and high availability in backend architectures?
Design with stateless services, use load balancers, implement caching (e.g., Redis), and leverage cloud-native tools like autoscaling groups or managed databases.
What is Identity and Access Management (IAM), and how do you apply it in a backend system?
IAM controls user authentication and authorization; implement it using OAuth2/JWT, role-based access control, and secure credential storage practices.
Explain your approach to debugging performance bottlenecks in a Node.js application.
Use tools like Chrome DevTools or clinic.js to profile the app, analyze logs and metrics, and isolate slow functions or resource-intensive processes.
How do you implement CI/CD pipelines for backend services?
Set up automated pipelines using GitHub Actions, GitLab CI/CD, or Jenkins to run tests, linting, build, and deployment tasks to environments like GCP or AWS.
Describe how Docker can be used in backend development workflows.
Docker standardizes environments, simplifies dependencies, and supports consistent builds across local, staging, and production with containerization.
What are the advantages of microservices architecture, and when would you use it?
Microservices promote modularity, independent deployment, and scalability. Use it when managing complex systems with distinct domains or scaling teams.
What challenges do you face when deploying applications on GCP, and how do you handle them?
Common challenges include managing IAM roles, cost control, and service configuration. Address them with least-privilege principles, budget alerts, and IaC tools like Terraform.

📋 Job Summary

Liminal, a global advisory leader in digital identity and IT security, is hiring a Mid-Level Backend Engineer to strengthen our scalable systems. You'll work remotely from Portugal or Brazil, using Node.js, MongoDB, and Google Cloud to build robust backend architectures. This full-time role offers a salary of €48,000–€55,000 (or BRL 339,757–401,531), with opportunities to innovate in cloud-native environments. Join us to shape the future of identity tech while collaborating with top-tier clients and industry experts.