Senior Machine Learning Scientist (ROAS) - Tokyo

Appier is hiring a Senior Machine Learning Scientist (ROAS) - Tokyo (Japan). Level rates it ; you can apply on Appier.

Level's read on this job

On Level's scale, this role is Builds AI ●●●●: the job is building AI systems.
Tools and skills the posting cites include PyTorch and TensorFlow.
Level classifies it as a senior role.
Level lists 66 other open roles at Appier.

AI in this role

pytorchtensorflow

About Appier

Appier is an AI-native Agentic AI as a Service (AaaS) company that uses artificial intelligence (AI) to power business decision-making. Founded in 2012 with a vision of democratizing AI, Appier’s mission is turning AI into ROI by making software intelligent. Appier now has 17 offices across APAC, Europe and U.S., and is listed on the Tokyo Stock Exchange (Ticker number: 4180). Visit www.appier.com for more information.

The Impact You’ll Make at Appier

Appier is seeking a Senior Machine Learning Scientist to join our Advertising Cloud Optimization team, which leads the development of core machine learning algorithms driving campaign efficiency and advertiser ROI. Our programmatic advertising platform operates at a massive scale, handling over multi millions queries per second (QPS), all powered by our proprietary deep learning models for bidding, pricing, and personalized content delivery.
In this role, you’ll build identify graph to enrich unified customer profile and also identify high purchase value users to drive ROAS by machine learning model.

What You’ll Work On

Leverage scientific methods to build identify graph and identify high-value users
Drive online experiments to continuously improve ROAS
Own the project independently.
Partner with product stakeholder, backend and frontend to provide measurement solution for our customers.

What We’re Looking For

Master’s or PhD’s degree in Computer Science, Machine Learning, Statistics, or related field.
3+ years of industry experience on identify graph, ID mapping and cross-device mapping in digital Ads related fields, and generate mapping and profile under large-scale data.
Proficiency in Python and SQL experience with modern ML frameworks (PyTorch, TensorFlow, etc.).
Strong ownership and collaboration skills.

#LI-AK1

How we rate this

Senior Machine Learning Scientist (ROAS) - Tokyo at Appier rates 95 out of 100 for how much of the daily work is AI. That makes it Builds AI (AI Level 4 of 4). The level is about AI in the job, not seniority.

Classification

Builds AI. The job is building AI systems.

●●●● Builds AI80 to 100
●●●○ Works on AI60 to 79
●●○○ Uses AI40 to 59
●○○○ Little AI0 to 39

Levels come from how often the tools, models and workflows of the role are named in the posting itself. Read the description and count the AI tools, models and workflows it names.

Key facts

Senior Machine Learning Scientist (ROAS) - Tokyo is an open job at Appier.
Level rates this role AI Level 4 of 4: Builds AI.
The role is based in Tokyo, Japan.
The job was posted on January 9, 2026.
Seniority: senior.
Applications are handled by Appier. Apply on Appier

Prepare for this job

Built from this posting and from similar jobs on Level.

Skills and AI tools this role asks for

PyTorchTensorFlow

Questions you could be asked

What's a project where you used PyTorch hands-on?
Walk me through how you've used TensorFlow in your day-to-day work.
How would you decide a model or AI system is ready to ship?
Tell me about a time a model underperformed in production. How did you find out, and what did you change?

Adapt your resume

List these exact terms on your resume: PyTorch and TensorFlow. An applicant tracking system matches the wording, not the idea.
Attach one line of real, concrete experience to at least one of them. A tool named with nothing behind it rarely survives a human read.
Lead with what you built, trained or shipped. This role is judged on the AI system itself, not the tools around it.

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