Backend Product Engineer

About the role

We're seeking Backend Product Engineers to build Migma's email workflow infrastructure: source imports, generation jobs, sending, analytics, and integrations. Full-time position based in Barcelona with competitive compensation.

Migma is an email workspace for brand teams. It connects source imports, brand context, visual editing, preflight checks, sending, export, and analytics. We're a small, talent-dense team building from Barcelona. We value high ownership, rapid iteration, and ego-free collaboration. We seek people who care deeply, challenge assumptions, and build with product judgment.

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

Our Tech Stack

• •Backend: Node.js, Python, Go
• •Databases: PostgreSQL, Redis, MongoDB
• •Email Infrastructure: Amazon SES, SendGrid, Resend, SMTP protocols
• •Message Queues: RabbitMQ, AWS SQS, Redis Pub/Sub
• •AI/ML Integration: OpenAI, Anthropic Claude, Langchain
• •Cloud: AWS (EC2, Lambda, S3, SES), Vercel, Cloudflare
• •DevOps & Monitoring: Docker, Kubernetes, GitHub Actions, Datadog, Sentry
• •Infrastructure as Code: Terraform, AWS CDK

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

How We Hire

• •Submit a brief application with your portfolio/GitHub and have an intro call with our team
• •Complete a backend programming exercise (building a mini email queue system)
• •Demonstrate your system design skills in technical interviews
• •Walk us through your most complex backend architecture project
• •Meet the team and discuss how you can help scale Migma.ai

About Your Application

Please submit your application in English - it's our primary working language. IMPORTANT: Include your GitHub profile or portfolio with production projects - Applications without demonstrable work will not be considered. Share examples of scalable systems you've built, especially any email or messaging infrastructure. We value all backgrounds and experiences - if you're excited about transforming email marketing, we want to hear from you.