Machine Learning Engineer, Recommendations

About the role

Northwind runs a marketplace with twelve million monthly buyers, and the ranking system that decides what they see is the highest-leverage surface in the product. You would own retrieval and ranking end to end: candidate generation, the ranking model, the online experiments that decide whether a change ships.

What you will do

Own the two-tower retrieval stack and the ranking model on top of it
Design and run online experiments, including deciding when a result is real
Reduce p99 ranking latency, currently 140ms, without giving up relevance
Work with the data platform team on point-in-time correct feature pipelines

What we look for

Production experience with a recommender or search system at scale
Strong grounding in experimentation and causal inference
Comfortable in the serving path, not just the training path
Python and SQL fluency; Go or Java welcome

What the assistant changed, and why

Change

Headline rewritten to "ML Engineer — retrieval and ranking at scale"

Why

The posting names retrieval and ranking four times. Your previous headline said "Machine Learning Engineer", which matched nothing specific.

Change

Marketplace search project moved from third position to first

Why

It is the only project on your resume with a two-tower architecture in it, and it is what this role is.

Change

Added the p99 latency number to that project bullet

Why

The posting names a specific latency target. Your project reduced p99 from 210ms to 90ms and the resume did not say so.

Change

Cut two bullets about computer vision coursework

Why

Irrelevant here, and they were pushing the ranking work onto page two.

What matched

Two-tower retrieval, built and shipped
Online experimentation, with a stated stopping rule
Serving-path latency work with measured results
Python and SQL throughout

What it would not stretch

No Go or Java on your resume — left as is rather than inflated; the posting calls it welcome, not required.
Your scale was 800k monthly users, theirs is twelve million. Stated accurately.

Awaiting your approval

The draft is written and the form is filled in on Northwind Systems’s own site. It sits here until you approve this one application. There is no approve-all, and nothing is submitted without you.