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Machine Learning Engineer, Detection (TOR)

Doppel · Toronto, Ontario

Location
Toronto, Ontario, Canada
Workplace
Hybrid
Employment
Full time
Level
Mid level
Posted
4 months ago

About this role

Why Join Doppel

Doppel is building the future of social engineering defense. Our AI-native platform uses agentic AI to protect executives, employees, customers, and brands from phishing, impersonation, fraud, and other AI-powered threats across digital channels. We help some of the world’s most recognized brands detect and dismantle attacker infrastructure while strengthening employee resilience through threat-informed training and simulation. By unifying Digital Risk Protection, Human Risk Management and Email Security, Doppel connects threats into a real-time intelligence graph to power faster disruption, smarter defense, and modern security awareness at scale.

Backed by leading investors including Andreessen Horowitz and Bessemer Venture Partners, and trusted by leading enterprises, Doppel is a rapidly growing Series C startup building the future of social engineering defense. Our team combines deep cybersecurity expertise, operational rigor, and startup velocity to solve some of the internet’s most urgent trust and safety challenges.

What We're Building

We're building the AI-native social engineering defense platform.

This means we're designing scalable systems that monitor billions of domains, social media accounts, apps, dark web forums, etc., and leverage AI agents to identify and neutralize digital threats.

What We're Looking For

We’re looking for a machine learning engineer to help build and scale the models and systems that power Doppel’s detection systems. Check out our blog post on how we set up our ML platform. As an MLE at Doppel, you will

  • Design, train, and deploy models for both batch and real-time inference that identify malicious or infringing content across diverse data sources.

  • Partner closely with the Detection and Infrastructure teams to ensure our ML systems scale with the volume of web data we ingest

  • Work on problems that range from NLP and embeddings to similarity search, classification, and anomaly detection

  • Collaborate directly with customers and internal stakeholders to translate real-world threats into production ML systems

You may be a fit if you:

  • Have experience building and deploying ML systems in production environments

  • Are comfortable working with large-scale datasets and distributed data processing frameworks

  • Understand the trade-offs between research-quality models and production-ready systems

  • Are excited about solving real-world problems where the adversary is constantly evolving

What We Offer

🚀 A mission-driven culture with low ego, high ownership, deep customer obsession, and exceptional talent density

🍽️ Free lunch and dinner in the office

🌴 Flexible PTO

✈️ Quarterly team offsites

Join Doppel

Doppel is the first platform built to dismantle digital deception at scale. We scan over 150 billion entities daily and deploy continuously adaptive AI SOC agents, paired with expert human analysts, to uncover and disrupt the infrastructure behind phishing, impersonation, and online fraud before attacks can spread. Our Threat Grid turns every customer signal into shared intelligence, making each disruption smarter, faster, and more effective.

We’re not just another cybersecurity company. We’re defining the future of social engineering defense, where trust is protected, and deception becomes unprofitable. Backed by top-tier investors and trusted by some of the world’s most recognized brands, Doppel is growing fast. If you’re driven to solve real-world problems with bold technology, we’d love to meet you.

As published by Doppel. Applications are handled on their site.

Skills this posting mentions

CArtificial IntelligenceFraud

About Doppel

In the era of AI, knowing what’s real is harder than ever. Social engineering threats are sophisticated, multi-channel campaigns. They lurk in your inbox, compromise your email channels, and weaponize fake profiles across social networks to deceive and defraud your people and your brands. Doppel is the agentic social engineering defense platform built to fight AI with AI. Unlike traditional systems that stop at detection and inbox scoring, Doppel delivers real-time disruption. We secure the inbox while executing automated takedowns on malicious sending infrastructures, lookalike domains, and rogue profiles at machine speed. By unifying Digital Risk Protection, Human Risk Management, and Email Security onto a single centralized platform, Doppel shuts down threats at their source. We safeguard every channel, move faster than attack speed, and turn global threat intelligence into a compounding network effect that keeps you ahead of the curve. Backed by Bessemer Venture Partners, a16z, George Kurtz - CEO, CrowdStrike, South Park Commons, Strategic Cyber Ventures, Aurum Partners, a group of athlete investors led by WNBA players Nneka Ogwumike, Breanna Stewart, and Kelsey Plum, who joined the round through the a16z Cultural Leadership Fund, Script Capital, 9Yards Capital, Sozo Ventures, NTT DOCOMO Ventures, and SVAngel.

All 18 openings at Doppel

One click, then it is written

Apply to Doppel with a resume written for this role.

Queue Machine Learning Engineer, Detection (TOR) and I read the posting, rewrite your resume against it, draft the cover letter, and score the fit. Then you press send, or press one button and I fill in Doppel’s form for you.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • 25 sent a week, free
  • No card
  • Nothing sent until you say so

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Put this to work

Paste your career in once. Every application after that is written for you.

Drop a resume or a LinkedIn URL. I rank the live openings against it, rewrite the resume and write a cover letter for the best of them, and fill in the employer's form when you press the button. You read, you decide what goes out.

  1. 01Drop your resume

    A PDF or a LinkedIn URL. About a minute, once.

  2. 02I rank the openings

    Every weekday morning, the live catalog scored against your history. Up to 20 worth your time, not two hundred links.

  3. 03Each one is written up

    Resume rewritten for the posting, a cover letter, a fit score. Press send, or let me fill in the form.

  • New matches ranked and written before you are up.
  • Every bullet stays inside what your history supports. Nothing invented.
  • Queued, submitted, interviewing, offer: one screen, not a spreadsheet.

500 free credits on sign-up. No card. Nothing is sent until you say so.

Listed from the job board Doppel publishes. Refolk is not the employer and does not handle their hiring. Applications go to Doppel directly.