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Open nowPosted 158 days ago

Senior Backend / Platform Engineer

Causa Prima6 open roles

Where
Madrid
Work mode
On site
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Your applicationOpen nowSenior Backend / Platform EngineerCausa Prima · Madrid

  1. YouYes, apply to this one.

  2. CV RocketCV written for this posting.

  3. 25 readersRecruiter, hiring manager, skeptic. Round after round.

  4. CV RocketApplied on Causa Prima's own form.

The reply lands in your private mailbox

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The clock on this job

Early applications get read.

8.2% of postings close within 7 days. Measured by our own scanner across the market. Causa Prima postings stay open a median of 12 days.

Share of postings closed within
  1. 1.9%1 day
  2. 3.8%3 days
  3. 8.2%7 days
  4. 15.2%14 days
  5. 34.1%30 days
This job: posted 158 days ago

Causa Prima median: 12 days open

The posting

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.
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    The review screen in CV Rocket: how each CV was read, round by round.

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    An interview invitation in the CV Rocket inbox, added to the candidate's calendar.
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