[Hiring] Founding Member of Technical Staff — Machine Learning @Vectoral

Role Description

Own whether we catch the fraud. Everything that goes into making a verdict. The signals, rules, trained models, thresholds, and evidence that it works.

What You’ll Work On

• The detection algorithm itself: a rule-and-group engine in Go that produces every live verdict.
• Signal groups like machine-paced behavior, birth cohort, probing, resource shape, value extraction, datacenter origin, and account risk, each with activation logic, per-customer presets, calibration, and cold-start handling for accounts we've barely seen.
• A LightGBM training pipeline (Python, psycopg, scikit-learn) that pulls labels and feature snapshots per customer, fits a binary classifier, Platt-calibrates on a temporally held-out split, and writes a candidate model.
• A model-replay worker that scores stored snapshots offline, allowing new changes to be evaluated against real historical traffic before affecting live verdicts.
• An adversarial red-team harness where a blind LLM adversary plays an abuser attacking a customer's product.

Benefits

• Competitive salary and equity
• Health, dental, and vision insurance
• Unlimited paid time off
• Flexible work hours

Qualifications

• Someone who is an applied ML or detection/anti-abuse practitioner.
• Experience shipping the model and the code that runs it in production, on a latency-sensitive path.
• Built fraud, abuse, anti-bot, risk, or security detection systems that operated against live adversaries.
• Fluent in gradient boosting, calibration, temporal train/test splitting, and precision/recall tradeoffs under severe class imbalance.
• Strong Python; can read and write Go, or will get there fast.

Why Join Us

• Build from day one on a product making a real impact with active customers.
• Founding engineering role: shape product, architecture, and company culture from the ground up.
• Significant technical ownership and direct influence over what we build and how we build it.
• Work with a tight, highly skilled team on problems where robust systems matter and where your work directly contributes to customer security and satisfaction.