Training user behavior foundation models and transparently sharing the research we do
We hold one of the richest behavioral datasets anywhere — events and replays of how real software gets used. Nobody has trained a foundation model on data like this. We're the first, starting with an encoder for the raw stream behind session replay.
We share the work as we go, through papers, conferences, and published progress.
What we're researching
Four tracks, each producing papers and technical reports.
- 01
Training a Replay Encoder model
In progressA foundation model pretrained on the raw event stream behind session replay, using a multi-axis RoPE built on additive Euler angles.
- 02
Training a session replay model
In progressOur current replay vision system uses Gemini to watch session recordings as video. We're building a new model that doesn't rely on computer vision and has access to additional data in PostHog, like logs.
- 03
Training a predictive user behavior model
In progressModeling what users do next from behavioral sequences.
- 04
Tuning a self-driving model
In progressTuning models to observe real product usage, diagnose what is broken, and act on it, benchmarked against real product problems.
We're hiring
Come take these models from whiteboard to arXiv, with the dataset, compute, and freedom to publish.
AI research engineer
2 open rolesTrain our own deep ML models on petabytes of product data and ship them into a self-driving product. This is not a Jupyter notebook job.
Want the bigger picture first? Meet the AI Research team.
Papers
Papers, preprints, and technical reports from the team.
Waltz, N. · 2024
Grafting: Making Random Forests ConsistentarXiv preprint · Published before joining PostHog ·
Waltz, N. · 2024
Time Series Clustering Using DBSCANarXiv preprint · Published before joining PostHog ·
The first paper from our current research is in progress and will be linked here on release.
Blog
What we learn — the wins, the errors, and the projects we cancelled.
Team
The AI Research team, and the founder who can't stay away.
Events
We talk about this work at meetups and conferences.
No research talks on the calendar right now
Check back soon, or browse everything else happening on the events page.