Juno
YC X26San Francisco, US · Founded 2025 · 2 employees · Hiring · 6 known investors
Juno is an AI health assistant that helps people with chronic illness track symptoms, identify patterns, and create reports for medical appointments, based on university research and user feedback from over 1,000 patients.
Also known as Juno Chat
Founders & leadership· Y Combinator alumni (X26)
Juno was founded in 2025 by Marshall Gould and Isaac Tolley.
Investors · 6
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Company profile
researched Aug 2026Juno develops an AI personal health assistant aimed at people living with chronic illness, a population the company describes as more than 1 billion people worldwide. The product supports conditions including fibromyalgia, long COVID, POTS, ME/CFS, EDS, endometriosis, PCOS, lupus and multiple sclerosis. Users interact by text or voice, and Juno builds a longitudinal health profile from conversations, biometrics and medical history.
Core features include personalised symptom guidance, automatic symptom logging through natural conversation, detection of triggers and patterns across weeks and months, and generation of appointment-ready PDF summaries that condense months of data for a clinician. The company frames the problem as long waits for appointments, short consultation windows, an average diagnosis time of 7.6 years, and the limitations of general-purpose chatbots that lack continuous patient context.
Juno is based in San Francisco, was founded in 2025, and is listed by Y Combinator in its Spring 2026 batch with a team size of two.
Founding story
Co-founders Isaac Tolley and Marshall Gould began building Juno after living with chronic conditions themselves: Tolley waited 14 years for an eosinophilic bronchitis diagnosis, and Gould lives with ME/CFS. They spent a year conducting research at Oxford and UCL on what makes people engage with medical chatbots, to inform how Juno asks questions and builds an understanding of each user's health.
Business model
Juno offers a consumer mobile application distributed through the App Store, used directly by patients rather than sold through clinicians in the material available.
Traction
Juno launched in October and reports 150,000+ patients supported globally; its Y Combinator launch post cited 80,000 users after six months, grown primarily through organic content, and more than 9,000 five-star App Store reviews.
Latest developments
Juno is listed in Y Combinator's Spring 2026 batch with David Lieb as primary partner, and is hiring a Founding Mobile Engineer and an AI Founding Engineer in San Francisco at $130K-$200K with 0.5%-1.0% equity.
▸Full profile — market position, technology, go-to-market, geography
Market position
Juno positions itself against general-purpose assistants such as ChatGPT and Claude, which it says give generic advice without continuous patient context, by maintaining a persistent longitudinal health profile and producing documentation that clinicians can read quickly.
Technology
The system builds a longitudinal health profile from conversational input, biometrics and medical history, logging symptoms automatically through natural language interaction by text or voice, identifying patterns and triggers over time, and exporting structured PDF summaries for clinical appointments.
Go-to-market
Growth has come primarily through organic content and word of mouth, with the company asking its network for referrals of people living with chronic illness and introductions to operators who have scaled consumer health products.
People living with chronic illness, including fibromyalgia, long COVID, POTS, ME/CFS, EDS, endometriosis, PCOS, lupus and MS.
Geography
Headquartered in San Francisco, California, with users described as global; founder research was conducted at Oxford and UCL in the UK.
Compiled by commissioned research from 8 cited public sources — announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed — not independently audited.
Competitors · 4
by search overlap
Companies competing with Juno for the same Google search keywords, organic and paid, via search-intersection analysis.
Timeline · 3
launches, deals, and filingsJuno was cited in a piece titled 'How These Three AI Healthcare Companies Are Restoring The Human Touch', listed as latest news on its YC profile.
Juno appears in Y Combinator's company directory as part of the Spring 2026 batch, with David Lieb as primary partner.
Juno launched its AI health assistant app in October, subsequently reporting support for 150,000+ patients globally.
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
In the news
Juno Bio Raises $3.8M to Support Vaginal Health - MedCity Newsmedcitynews.com · Jul 2026
Startup Juno Bio raises $3.8m for smarter women’s diagnosticslongevity.technology · Jul 2026▸Research sources · 8
primary sources listed
- Junojunocompanion.com · web
8 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does Juno do?
- Juno is an AI health assistant that helps people with chronic illness track symptoms and prepare reports for doctors.
- Who founded Juno?
- Juno was founded by Marshall Gould, Isaac Tolley in 2025.
- Who are Juno's investors?
- Juno's investors include Lobster Capital, Sterling Road, Y Combinator, Ada Ventures, Artesian, Entrepreneur First.
- Where is Juno headquartered?
- Juno is headquartered in San Francisco, US.