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NYC Product Leader

Harrison
Johnson.

Former founder with 10+ years of product experience across B2B SaaS, marketplaces, and consumer mobile.

I love building, scaling, and operating tech products. I've been through two acquisitions, joined a company as Employee #1, led a product org of 9 engineers and 2 designers across 7 timezones, and shipped mobile features and hardware devices to millions of pet owners across the globe.

01

Selected Work

flagship

International Expansion & Localization

FlagshipFi · International · 2025–26
i18n / l10nCross-borderAI-assisted

Owned internationalization & localization across 5 repos and 7 languages with 15+ engineers; planned cross-border fulfillment, operations and localized CX for new-market readiness.

marketplace

Marketplace Payments & Liquidity at Scale

MarketplaceManaged by Q · Employee #1
PaymentsTwo-sidedLiquidity

First employee; owned the marketplace product across three pods from pre-seed to acquisition. Scaled compliant payments (Stripe, Avalara) and redesigned the marketplace to an open-bidding model.

growth

Activation & Retention

GrowthFi · 2025–26
ActivationRetentionExperiments

Cut cancellations needing a human ~80% → 15%; launched a free-trial program with 60%+ survivorship and retention loops across live activities, push, email and SMS.

0 → 1

Founder → Operator

0 → 1Driveway → Chameleon
AcquiredLeadershipPLG

Founded and sold a venture-backed marketplace startup ($4M raised); then led a 14-person team across 7 time zones through post-acquisition integration.

02

Built

karma

Karma

Python · FastAPI · local embeddings
Knowledge graphRAGLocal-first

A personal knowledge graph that auto-discovers links between notes using on-device embeddings — no manual linking. CLI, web UI, and a graph-aware chat. 112 tests.

GitHub ↗
claude-remote

Claude Remote

Python · WebSockets · PWA
VoiceToolingPush-to-talk

Voice control for Claude Code from your phone: a push-to-talk PWA that transcribes locally and types into your terminal over a token-gated WebSocket.

GitHub ↗
behavior-classifier

BehaviorClassifier

Swift · CoreML · on-device training
TinyMLOn-device trainingPrivacyiOS

A 549-parameter, 2 KB CoreML model that classifies behavioral state from ambient signals — WiFi, Bluetooth, Focus mode, time — and trains entirely on-device from corrections. No server, no account, nothing transmitted. The privacy guarantee is architectural. Proof that tinyML is a one-day project, not a research paper.

GitHub ↗
Contact

Let's talk.

Email is the fastest way to reach me, or find me on LinkedIn.

EMAIL   harrisonhjohnson@gmail.com
LINKEDIN   in/harrison-johnson
BASED   New York City
harrison.build · the portfolio runs behind it
NYC  ·  SYSTEM 7.0.1  ·  HARRISON.BUILD