Software Engineer

Senior Full-Stack Developer — Backend & AI Focus

Remote | Indonesia / Vietnam | Full-time | Long-term | EU Working Hours

About the Role

OUR CLIENT is a European SaaS company building a digital productivity platform for field sales teams.

Their product helps sales professionals digitize business contacts and meeting information — including business cards, LinkedIn contact details, voice notes, and meeting notes — and automatically connect that information with CRM platforms such as Salesforce and HubSpot.

They are looking for a Senior Full-Stack Developer with a strong Backend focus to join their engineering team and take ownership of backend architecture, scalability, AI integrations, and the reliability of their web application.

This is not a role for someone who has simply used AI coding assistants. The ideal candidate has hands-on experience integrating AI into production software, including the backend infrastructure, APIs, workflows, and architecture required to make AI features reliable and scalable.

What You'll Do

• Design, develop, and maintain backend services and APIs for a production SaaS platform.
• Take ownership of backend architecture, scalability, performance, and maintainability.
• Build and integrate AI-powered capabilities into existing SaaS products.
• Design the server-side infrastructure behind AI features, including APIs, services, data flows, and integrations.
• Work with large and complex codebases and help improve their architecture over time.
• Identify architectural bottlenecks and propose practical solutions for scalability and maintainability.
• Develop frontend features when required using React and TypeScript, while maintaining a strong backend focus.
• Build and maintain integrations with external systems and APIs.
• Set up and improve automated testing frameworks, test environments, and CI/testing workflows.
• Write clean, maintainable, production-ready code.
• Collaborate directly with a European engineering/product team and communicate technical decisions clearly in English.
• Debug production issues and contribute to improving system reliability and developer experience.

Must-Have Experience

• Senior-level software engineering experience with strong backend expertise.
• Strong production experience with Node.js.
• Strong experience with TypeScript.
• Hands-on experience with Express.js or comparable Node.js backend frameworks.
• Solid experience building and maintaining REST APIs / backend services.
• Strong experience with React and modern frontend development.
• Proven experience working with AWS or comparable cloud infrastructure.
• Hands-on experience implementing AI integrations in production applications.
• Experience with the backend/server-side architecture required to support AI features, rather than only consuming AI tools.
• Experience working with large, complex, or mature codebases.
• Experience improving backend architecture, scalability, performance, or maintainability.
• Experience setting up or significantly improving automated testing frameworks/environments.
• Strong understanding of software architecture, APIs, databases, asynchronous processes, and production systems.
• Strong English communication skills and the ability to work directly with a European team.

Strongly Preferred

• Experience integrating LLMs or other AI services into SaaS products.
• Experience building AI-powered workflows, automation, or intelligent features.
• Experience with AI APIs, model providers, prompt workflows, RAG, agents, or similar production AI systems.
• Experience modernizing or scaling legacy/mature SaaS codebases.
• Experience establishing testing strategies for large applications.
• Experience working with distributed or international engineering teams.
• Previous experience working with European or international clients.

Working Arrangement

• Remote
• Full-time, long-term engagement
• Candidates must be comfortable covering full EU business hours.
• The client primarily operates during European business hours, so consistent availability during the EU workday is required.
• Direct collaboration with a European engineering/product team.
• Strong English communication is required.

Why This Role

This is an opportunity to work on a real production SaaS product where you'll have meaningful ownership over:

• Backend architecture
• AI integration
• System scalability
• Large-codebase improvements
• Automated testing
• Production engineering

If you're a senior engineer who can go beyond simply implementing tickets and can think about architecture, AI infrastructure, scalability, and long-term maintainability, we'd like to hear from you.