Backend Product Engineer

We're seeking exceptional Backend Product Engineers to build the infrastructure powering the future of AI-driven email marketing. You'll design and scale systems that handle millions of emails, real-time content generation, and seamless integrations. Full-time position based in Barcelona with competitive compensation.

Migma.ai transforms email creation from a multi-day process into an instant task. Using AI that understands your brand and content sources, anyone can generate compelling, responsive emails without designers, developers, or marketing expertise. We're democratizing professional email marketing for millions of businesses worldwide. Thousands of companies and agencies are already using Migma.ai to slash costs, maximize ROI, and send emails that actually convert. And we're just getting started. We're a small, talent-dense team building a category-defining company from Barcelona. We value high ownership, rapid iteration, and ego-free collaboration. We seek people who care deeply, challenge assumptions, and are driven to build something transformative.

What you'll do

• Design, implement, and maintain backend services, APIs, and email delivery infrastructure
• Build robust integrations with email service providers (SES, SendGrid, Resend) and handle deliverability challenges
• Create scalable systems for template management, dynamic content generation, and subscriber management
• Architect data pipelines for analytics, tracking opens/clicks, and managing unsubscribes
• Own backend systems end-to-end: architecture, implementation, deployment, monitoring, and optimization
• Collaborate with frontend, AI, and product teams to translate ambitious ideas into robust, scalable features
• Implement caching strategies and optimize database queries for sub-second response times
• Build webhook systems for real-time email events and third-party integrations
• Shape our backend architecture, API standards, and technical strategy as we scale

What we're looking for

• Based in Barcelona (on-site/hybrid working model)
• 5+ years of experience designing, building & scaling backend systems for production products
• Fluency in Node.js, Python, with strong API design skills
• Deep understanding of distributed systems, message queues, caching strategies, and scalability patterns
• Experience with email infrastructure (SMTP, deliverability, bounce handling, rate limiting)
• Proven experience integrating with AI/ML systems and third-party APIs (CRMs, e-commerce platforms, analytics)
• Strong understanding of database design (PostgreSQL, Redis, MongoDB) and query optimization
• Experience with event-driven architectures and real-time data processing
• Strong product instincts: you know how to balance fast delivery with building for the long term
• Fluent English communication skills (written and spoken) - essential for team collaboration
• Portfolio or GitHub profile with production-level projects is mandatory - Please do not apply without demonstrable work
• Message Queues: RabbitMQ, AWS SQS, Redis Pub/Sub
• AI/ML Integration: OpenAI, Anthropic Claude, Langchain

What We Offer

• Highly competitive salary - We believe in compensating top talent accordingly
• Full-time position based in our Barcelona office
• Work with cutting-edge AI technology in a rapidly growing market
• High impact role in a small, ambitious team
• Professional growth opportunities as we scale
• Modern office in the heart of Barcelona