Description du Poste
Post Quantum Cryptography | Cybersecurity | We're hiring
CryptoNext Security is a deeptech startup specializing in
post-quantum cryptography . We help businesses and institutions prepare for a world where quantum computers will break today's cryptography. Our customers include major banks, defense actors, telecom operators, and large enterprises securing their most sensitive infrastructures.
On a daily basis, you will
As Senior Probe Appliance Engineer you will take full technical ownership of the
COMPASS probe appliance , a high-performance hardware and software component responsible for packet capture, telemetry extraction, and encrypted traffic analysis. You will work across the full lifecycle of the appliance: system installation, kernel-level tuning, security hardening, performance optimization, reliability engineering, and operational excellence.
System, OS & Installation
Deploy, configure, and maintain the
COMPASS probe appliance
(hardware + Linux OS).
Perform OS-level and kernel-level hardening (CIS benchmarks, secure boot, file integrity, access control).
Network Performance & Packet Capture
Optimize the appliance for high-throughput packet capture using DPDK, AF_XDP, or zero-copy capture frameworks.
Tune network interfaces, NIC offloading, IRQ distribution, and NUMA alignment.
Build low-latency, high-performance data paths.
Data Ingestion & Pipeline Integration
Guarantee secure, reliable ingestion into
Kafka
pipelines.
Ensure compatibility and performance with downstream data and platform components.
Engineering Collaboration
Work closely with R&D teams to integrate parsing modules, firmware updates, and kernel patches.
Document operating procedures (installation, upgrades, troubleshooting).
Observability, Monitoring & Reliability
Implement monitoring (metrics, logs, health checks).
Maintain configuration management and full traceability of system changes.
Run benchmarks, stress tests, and capacity planning.
Deployment Support
Provide support to customers and integrators during field deployment (occasional on-site presence).
Security
Contribute to the appliance's security model: access control, secure boot chain, encryption (at rest and in transit), update pipeline security.
Requirements
The skills you'll need
Must-have
10+ years of experience in system engineering, network engineering, or infrastructure security.
Master's degree from a French engineering school or equivalent.
Deep expertise in:
Linux system administration
Kernel tuning and OS-level performance optimization
Networking, packet capture, and traffic analysis
Experience with:
CIS, NIST, or ANSSI hardening methodologies
Hardware optimization (CPU pinning, NUMA, NIC queues, hugepages)
Kafka or streaming ingestion technologies
Automation scripting (Bash, Python, Ansible)
Excellent documentation skills and rigor.
Fluent in English.
Bonus
Experience with DPDK, AF_XDP, or similar high-throughput capture frameworks.
Background in NDR / IDS / DPI appliances or packet inspection.
Knowledge of secure boot chains, TPMs, or hardware-backed security.
Experience with embedded Linux or containerized environments.
Familiarity with Elasticsearch or observability stacks.
Exposure to cryptographic or secure distributed systems.
The team you'll be joining
You will join the
COMPASS product engineering team , working closely with:
R&D engineers building probe parsing logic and cryptographic modules
Data engineering & platform teams managing ingestion and observability pipelines
The Head of Engineering and CTO for architecture and long-term strategy
Product and QA teams to ensure reliability, performance, and compliance
You will be the reference engineer for everything related to probe performance, appliance security, and kernel-level tuning.
Our recruitment process
HR intro
โ get to know each other and understand your background.
Technical interview
with senior engineers + Head of Engineering (Linux, networking, OS tuning, probe performance).
CTO meeting
โ architecture, deep-dive, and cultural fit.
Offer & onboarding
โ welcome to CryptoNext!
Benefits
Shape a core component of a next-generation cybersecurity product.
Work on challenging, low-level engineering problems involving kernel optimization and network performance.
Collaborate with senior engineers and cryptography experts.
Flexible hybrid/remote work with a central Paris office.
Competitive compensation aligned with seniority.
Direct impact on the technical backbone of a quantum-safe observability platform.
Seniority level : MidโSenior level
Employment type : Fullโtime
Job function : Engineering and Information Technology; Industries: Software Development
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