Senior Engineer; Fraud Remote Remote

Position: Senior Engineer (Fraud) New Remote Remote, United States
Apollo.io is the leading go-to-market solution for revenue teams, trusted by over 500,000 companies and millions of users globally, from rapidly growing startups to some of the world's largest enterprises. Founded in 2015, the company is one of the fastest growing companies in SaaS, raising approximately $250 million to date and valued at $1.6 billion. Apollo.io provides sales and marketing teams with easy access to verified contact data for over 210 million B2B contacts and 35 million companies worldwide, along with tools to engage and convert these contacts in one unified platform.

By helping revenue professionals find the most accurate contact information and automating the outreach process, Apollo.io turns prospects into customers. Apollo raised a series D in 2023 and is backed by top-tier investors, including Sequoia Capital, Bain Capital Ventures, and more, and counts the former President and COO of Hubspot, JD Sherman, among its board members.

Your Role & Mission
This role sits at the intersection of engineering, security, and fraud operations. The hired candidate will play a critical role in evolving Apollo’s abuse detection and account security capabilities.

As a  Senior Engineer (Fraud) , you’ll work closely with Fraud Operations, Data Science, Application Security, and Product to modernize abuse detection logic. You'll prototype and deploy new risk decisioning systems and build the technical foundation for new fraud decision models over the next several quarters. This role is ideal for a senior engineer who thrives in ambiguous, data-driven problem spaces and enjoys building systems that protect our customers and business.

Daily Adventures & Responsibilities

Lead the implementation and ongoing improvement of abuse detection services and customer account security features

With assistance of technical leadership, implement a home‑grown risk decision engine

Build and maintain APIs to support extensible, low‑latency risk decisioning

Research and analyze abuse tools and attacker tactics to inform detection strategies

Participate in fraud incident triage and lead development of mitigations and remediation

Collaborate with Data Science and Data Engineering on model feature and system design

Work closely with Fraud Operations and Application Security to align detection and response

Stay informed on fraud prevention trends and apply relevant insights internally

5+ years building production backend systems in a SaaS or similar environment

Experience designing scalable backend services; exposure to risk or decisioning systems a plus

Proven track record of designing customer‑first features

Ability to explore and validate ideas using imperfect or partially structured data

Strong foundation in secure system design and layered defenses

Comfortable presenting designs to both technical peers and senior stakeholders

Familiarity with common abuse vectors, evasion techniques, or scraping patterns

Strong ownership mindset and ability to prioritize effectively

Fraud, trust & safety, or security‑adjacent experience preferred

Clear written and spoken English communication

Our tech stack  is React/Redux/NodeJS on the frontend, Ruby/Ruby on Rails/Mongo

DB/Elasticsearch on the backend, and Kubernetes/Docker/Ansible/Terraform in infrastructure.

Apollo.io Tech Blog :  Deep dives into engineering, product design, and company‑culture stories from the Apollo team, offering behind‑the‑scenes insight into how Apollo builds and scales its B2B sales platform.

The listed Pay Range reflects the total cash compensation inclusive of annual base salary and annual bonus as applicable. For sales roles, the range provided is the role’s On Target Earnings ("OTE") range, meaning that the range includes both the sales commissions/sales bonus target and annual base salary for the role. This salary range may be inclusive of several career levels at Apollo and will be narrowed during the interview process based on a number of factors, including the candidate’s experience, qualifications, and location.

Applicants interested in this role who are not located in the US may request the annual salary range for their location during the interview process.

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