Juno Reaches $600K Run Rate for AI Health Companion, Hires Founding Team in San Francisco

Juno is building an AI personal health assistant designed to help more than one billion people living with chronic illnesses track symptoms, organize medical histories, and obtain faster diagnoses. Founded in 2025 and backed by Y Combinator's P26 batch, the company has scaled to a $600,000 annual run rate supporting over 50,000 active patients worldwide.

Diagnosing chronic conditions like fibromyalgia, long COVID, postural orthostatic tachycardia syndrome (POTS), and chronic fatigue syndrome takes an average of 7.6 years. Patients often wait months for brief 15-minute appointments where doctors lack full context on daily symptom fluctuations. Juno bridges this gap by building longitudinal health profiles through daily conversations, biometric tracking, and medical record imports.

Medical Research Meets Patient Experience

Juno was co-founded by CEO Isaac Tolley and CTO Marshall Gould, who both grew up managing chronic conditions. Isaac Tolley studied molecular biology at UCL, ranked first in his class, and led a 35-person synthetic biology team before conducting neuroscience research. Marshall Gould holds a master's degree in genomic medicine from the University of Oxford and authored research on how chronic illness patients interact in digital communities.

Prior to building Juno, the co-founders spent months conducting research and patient interviews at Oxford and UCL to develop a specialized engagement layer for health dialogue. The system asks targeted questions based on clinical context and daily biometrics from devices like Whoop and Oura, creating actionable diagnostic summaries that patients can share with specialists.

In an interview on The Lobster Talks Podcast, Marshall Gould noted that compute costs represent the startup's largest expense, driven by heavy usage across more than 20,000 daily active users. To support high token consumption, Juno accepted OpenAI's $2 million token offer for Y Combinator batch founders. Speaking on the No Fixed Route Podcast, Gould explained how the assistant recently identified a life-threatening antibiotic allergy in real time by connecting daily symptom reports with a user's active prescriptions.

According to coverage by Health Tech World, the app logged over 150,000 downloads during its first eight months of operation.

Expanding the Technical and Marketing Teams

To expand its core reasoning engine and mobile app, Juno is recruiting its initial engineering hires in San Francisco, CA.

The team is hiring an AI Founding Engineer ($130,000 to $200,000 USD per year, onsite in San Francisco). Working directly with the founders, this engineer will architect conversation intelligence, health reasoning algorithms, retrieval systems, and LLM reliability pipelines.

Juno is also recruiting a Founding Mobile Engineer ($130 to $200,000 USD per year, onsite in San Francisco). This role owns core features across the mobile application, including interaction quality, UI animations, onboarding, personalization, local memory, voice interface, and retention mechanics.

Alongside engineering, Juno relies heavily on social media and patient community engagement to drive organic user acquisition. To scale its public presence, the company is hiring a Social Media Manager ($60,000 to $110,000 USD per year, onsite in San Francisco) to own short-form video creation across TikTok, Instagram, and YouTube Shorts, appear on camera, and collaborate with patient creators.

Additionally, the company has an open position for a Social Media & Content Intern ($2,000 to $3,000 USD per month, remote US or onsite in London or San Francisco). The intern will develop script hooks, film health explainers, and edit short video demos.

Open Positions at Juno

See all open roles at Juno