Per WinrothProduct Manager & Co-founder

Dynamic Product Manager with experience delivering data-driven solutions across music marketing, gaming, and digital platforms.

Currently building on an operating system for AI agents I wrote myself: Subfeel, Got Cosy and Got Hush, shipped solo in 2026.

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Professional Summary

Proven expertise leading cross-functional teams to create and execute product strategies, roadmaps, and growth initiatives that drive user engagement and revenue. Adept at leveraging data insights to inform decision-making, ensuring compliance with global privacy standards, and managing stakeholders at all levels.

Work Experience

I've spent my career building innovative products across the music and digital space.

Independent Product & AI Developer

Self-employed

2026–Present

Building AI-native products end to end, solo.

Parasition

Advisory

Sep 2025–Apr 2026

Advised Parasition, whose AI Hugo is a marketing co-working space for the music industry, on product and go-to-market.

Warner Music Group

Product Manager

2023–2024

Led development of WMG's D2C FanApp platform with focus on privacy compliance and user experience.

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Current Projects

Four live products shipped solo in 2026, plus prior work below.

Subfeel

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The feeling underneath. Reads nine specific feelings in what people already wrote, with founder-judged ground truth and a locally fine-tuned model. Formerly Feel Layer; the measurement layer under Got Cosy and Got Hush.

InstrumentMCPFeelings

Got Cosy

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6,300+ hotels scored for cosiness from guest reviews. AI-consumable graph exposed via MCP.

AI ScoringMCPHotels

Got Hush?

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Launched July 2026. 813 hotels with evidence-gated quiet scores deduced from guest reviews.

AI ScoringEvidence-GatedHotels

2026

Buy-Again Score

buyagainscore.com

Buy-Again Score

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Product registers answering one question: would owners buy it again. Launching soon.

Product RegisterReviewsLaunching Soon

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Core Skills

My professional toolkit built across multiple industries and roles.

AI systems and agents

Runs projects on DIE-OS, an operating system for AI agents he built and published: 14 constrained roles, 14 gates, append-only laws, a mechanical checker. Frontier models for judgment, cheaper models for execution.

Measurement and evaluation

Nine feeling detectors judged blind against his own verdicts, sealed exams with frozen bars and look budgets, an adversarial reviewer that files predictions before results exist. Over 2,900 blind verdicts in the last month alone.

Local models and fine-tuning

Fine-tuned 14B models (QLoRA on rented L40S, MLX on Apple silicon) that beat frontier models on domain labeling. Moved image analysis to a free open-weight model on local hardware.

Analytics and data

Built the scoring pipelines behind Got Cosy (6,300+ hotels on a calibrated 0 to 10 scale) and Got Hush (813 hotels, evidence-gated), plus a corpus engine that discovers, licenses and ingests review datasets continuously.

Product management

Twelve years of it: Warner Connect from zero to WMG's most-used marketing tool, 100M+ users, SEK 250M+ revenue; now shipping solo, end to end, from data to live product.

Stakeholder management

Global teams at Warner Music, artists and their management (Coldplay, David Guetta, Ed Sheeran), executive stakeholders, and advisory work with an AI marketing startup.

CRM and marketing

Audience segmentation with predictive models that lifted email conversion from 12.5% to over 35%; answer-engine optimization so AI assistants cite the products.

Privacy and compliance

Owned privacy for Warner Connect across 100M+ users and 10,000 digital campaigns, and privacy compliance for WMG's D2C FanApp across global territories.

Want help with something like this?

Email me.

perwinroth@gmail.com linkedin.com/in/perwinroth