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Senior Backend / Platform Engineer

On-site in Madrid·Full-time·Added 5 months ago

This job was published 5 months ago

Causa Prima

6 open roles

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Overview

Job details

Full-time hours
Per the ad.

Requirements

Have the right to work in Spain
Causa Prima doesn't mention sponsorship in the ad.
Work in English
English is required, per the ad.
Work on-site in Madrid
No relocation package mentioned.
Have 5+ years of experience
Senior-level role.

The role

You'll own the platform our agents run on - event-driven architecture, data pipelines, integrations with customer accounting systems, and the infrastructure that makes everything reliable, auditable, and fast.

What you'll do

Event store - Append-only PostgreSQL with tamper-evident hash chaining, real-time event distribution, agent replay and recovery, schema versioning.
Cryptographic signature infrastructure - Key management, signature verification on all agent events, approval chains for external actions.
Workflow Constraint Engine - The gateway that verifies authorization before any external action (email, payment, API call) proceeds.
PII Vault & GDPR compliance - Isolated, encrypted storage for personal data. Right to erasure. Data residency per region.
Multi-tenancy - Row-level security, tenant isolation across all data stores, tenant-scoped LLM API keys.
Authorization (Cerbos) - Attribute-based access control for agents and humans. Deterministic policy evaluation - LLMs never make auth decisions.
MCP security layer - Authentication, capability-based scoping per partner, and rate limiting for the Model Context Protocol endpoint.
Database architecture - PostgreSQL schema design, indexing strategy, performance tuning, read replica topology.

What we're looking for

3+ years experience with Python and/or TypeScript in production.
5+ years designing backend platforms for production systems.
Strong systems design skills - this is the primary requirement. You think in boundaries, contracts, failure modes, and scaling characteristics.
Deep PostgreSQL knowledge - RLS, indexing tradeoffs, event sourcing patterns, schema evolution.
Strong application security architecture skills: encryption models, key management, auth patterns.
Experience with policy-as-code authorization (Cerbos, OPA, Cedar, or similar).
Strong code review skills for security-sensitive AI-generated code.
Nice to have:
- Cryptographic primitives in production (digital signatures, hash chaining, application-layer encryption).
- Event streaming platforms (Kurrent, Redpanda, Kafka).
- SOC 2 or GDPR compliance engineering.
- Fintech or regulated-environment background.

About Causa Prima

Causa Prima is a technology company focused on developing AI-driven agent platforms and enterprise software solutions. Based in Madrid, Spain, the company operates at the intersection of artificial intelligence, platform engineering, and product development, serving clients that require advanced automation and intelligent systems. With a team of engineers, product specialists, and marketers, Causa Prima is building scalable infrastructure and AI agents for real-world business applications.

Causa Prima has its main office in Madrid, Spain, and is actively hiring for senior engineering and product roles, making it an attractive destination for international tech professionals looking to work in Spain's growing AI ecosystem. The company's work culture emphasizes innovation, technical excellence, and cross-functional collaboration, offering opportunities for relocation and career growth in a dynamic startup environment.

Headquarters: Madrid, Spain
In Spain: Madrid

Good to know if you are moving

Based in Madrid, offering a central location in Spain's tech hub with a vibrant startup scene.
Hiring for senior engineering roles, indicating a focus on building a strong technical team.
The company works on AI and LLM technologies, which are high-demand fields globally.
As a smaller company, employees may have more impact and ownership over projects.

All open roles at Causa Prima