Senior Data & Platform Engineer
Cryptonext Security
Who we are
CryptoNext Security is a deeptech startup specializing in post-quantum cryptography. We help businesses and institutions prepare for a world where quantum computers will challenge today’s security standards.
Our clients include major financial institutions, defense actors, telecom operators, and global enterprises seeking to future-proof their cryptography.
On a daily basis, you will
As Senior Data & Platform Engineer, you will lead the design, setup, and operation of the entire data backbone powering COMPASS, our observability and orchestration platform for post-quantum cryptography deployments.
Your missions include:
Data Modeling & Governance
- Define and maintain the end-to-end data model for COMPASS (entities, relationships, vocabulary, lifecycle).
- Translate product requirements into robust database schemas, indexing strategies, and normalization/denormalization choices.
- Ensure semantic consistency and data governance rules across all services.
Ingestion, Streaming & Storage
- Design, validate, and maintain ingestion pipelines using Kafka, ensuring data correctness and consistency.
- Define the canonical formats exchanged across Kafka (ingestion), PostgreSQL (storage), and Elasticsearch (search).
- Validate and standardize data structures produced by probes, sensors, and backend services.
Backend Collaboration & API Contracts
- Work closely with backend teams to design API-level data contracts aligned with the data model.
- Optimize queries, indexes, and persistence strategies for real-time workloads and analytics.
Observability & Data Quality
- Contribute to platform-wide observability by defining structured logs, metadata standards, and ingestion patterns.
- Promote best practices for data quality, versioning, retention, and schema evolution.
The skills you'll need
Must-have
- 15+ years of experience in software or data engineering in a distributed or complex environment.
- Master’s degree from a French engineering school or European equivalent.
- Deep expertise in:
- Data modeling & relational schema design
- PostgreSQL administration & performance optimization
- Kafka (setup, topics/partitions, consumer groups, schema registry, monitoring)
- Elasticsearch / ELK stack
- Strong hands-on experience with:
- Stream processing architectures
- ETL/ELT workflows
- Data lifecycle management
- Proven ability to design data flows with clean, contract-based schemas.
- Strong commitment to code quality, documentation, and operational reliability.
- Fluency in English.
Bonus
- Experience with ClickHouse, Grafana, or Prometheus.
- Understanding of secure data handling and cryptographic components.
- Familiarity with AWS/GCP or hybrid on-prem architectures.
- Background in cybersecurity, observability, or high-throughput systems.
- Experience with large-scale data retention strategies and analytics workloads.
The team you’ll be joining
You will work closely with:
- The R&D engineering team building CryptoNext’s cryptographic and observability products.
- Backend engineers designing APIs and distributed services.
- The Head of Engineering and CTO for architecture, strategy, and long-term product evolution.
- Product and QA teams to ensure data quality, reliability, and consistency across the platform.
You will be the reference person for all data-related decisions and architecture within the COMPASS squad.
Our recruitment process
- HR Intro – a first conversation to understand your background and expectations.
- Technical Interview with a senior engineer and the Head of Engineering (Kafka, PostgreSQL, ELK, data modeling).
- CTO Meeting – deep dive on architecture, COMPASS roadmap, and cultural fit.
- Offer & onboarding — welcome to CryptoNext!
What’s in it for you at CryptoNext
- Join a deeptech company at the forefront of post-quantum cybersecurity.
- Build the core data infrastructure of a cutting-edge observability platform.
- Collaborate with world-class cryptographers and software engineers.
- Flexible hybrid/remote policy and office in central Paris.
- Competitive compensation aligned with seniority and expertise.
- Direct impact on a product used by major financial and defense clients.
- A chance to shape the future of quantum-safe data engineering.