Senior Data

*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.

Requirements
*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
Benefits
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
  .