5 months ago
Paris, FranceStaff+
Responsibilities
- Own the fingerprinting roadmap from signal collection in iOS, Android, and server-side APIs through feature-engineering pipelines.
- Build and harden device-fingerprinting systems for persistent device identity, rooted or emulated device detection, hardware attestation, and spoofing resistance across web and mobile.
- Develop network-intelligence signals including IP reputation, proxy and VPN detection, datacenter detection, TLS and JA4 fingerprinting, carrier and MCCMNC enrichment, and residential versus commercial traffic classification.
- Apply machine learning for anomaly detection, fraud-ring clustering, suspicious-pattern classification, and adversarial robustness.
- Integrate low-latency fingerprinting features with Prelude’s real-time authentication risk-scoring engine.
- Research attacker techniques, anti-detect tooling, automation frameworks, and bypass methods.
- Define engineering standards, research practices, and scalable data pipelines for a future fingerprinting team.
Requirements
- 5+ years of experience in fraud detection, bot mitigation, mobile security, detection engineering, or a relevant field.
- Production experience shipping systems rather than only research prototypes.
- Deep knowledge of mobile hardware signals, OS-level attestation, browser fingerprinting APIs, and spoofing or emulation detection.
- Hands-on experience with TLS fingerprinting, IP enrichment, proxy and VPN classification, AS number analysis, and carrier-level signals.
- Applied machine-learning experience in security, including feature engineering, anomaly detection, clustering, classification, training, and production deployment.
- Knowledge of attacker techniques involving emulators, spoofing, anti-detect browsers, and residential proxy networks.
- Fluent English.
- Familiarity with phone or SIM authentication, GSMA intelligence, or telco APIs is a plus.
- Experience with JA4 or other network-fingerprinting techniques is a plus.
- Proficiency in Go, Rust, or Python for backend or data work is a plus.
- Experience with SQS, Kafka, ClickHouse, or Redshift is a plus.
- iOS or Android SDK internals knowledge is a plus.
- Published research, open-source contributions, or technical writing in fraud or bot detection is a plus.
Benefits
- Flexible remote policy
- 100% travel to the office subsidised
- Health insurance via Alan
- Urban Sports Club gym membership
- Laptop and phone provided, including for on-call rotations
- Swile meal vouchers
- Free snacks and drinks in the office
- Annual offsite
- Opportunity to build a product from 0 to 1
Tech Stack
Categories
About Prelude
Prelude builds a security control validation platform for enterprise security teams to continuously test, monitor, and optimize defenses against emerging threats. The SaaS provides visibility into control configurations, maps them to current threat techniques, and recommends fixes to improve coverage and compliance. The company is privately held and raised a Series A in 2022.