Get an API keyGet an API key10 Y Combinator companies with a founder who worked at Mozilla before.
Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.
Human InterestS15
DeepnoteS19Human Interest+12%DeepnoteS19
LeadGenius−3%| Company | Batch | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
The 401(k) for small and medium-sized businesses. | S15 | 930 | +12% | +20% | 36 | $915M | Undisclosed round$100M, Oct 2025 |
LeadGenius is an account-based marketing and lead generation… | S11 | 398 | −3% | −3% | 0 | $30.4M | Seed$3M, Sep 2019 |
A better data science notebook. | S19 | 22 | +29% | −31% | YC | $23.8M | Series A$20M, Jan 2022 |
 Generate fast, reliable APIs for any platform | W24 | 5 | 0% | −17% | 0 | ||
 AI Agents to win denied health insurance claims. | X25 | 4 | −33% | 0 | |||
 | S20Acquired | 4 | −20% | −56% | 0 | $11.4M | Undisclosed round$5M, Oct 2023 |
 Collaborative data noteboook for business teams | S19Acquired | 4 | 0 | $150K | YC investment$150K, Aug 2019 | ||
 VR space of immersive utilities | W18 | 1 | 0 | $1.1M | Seed$1.1M, Jul 2018 | ||
 Realtime collaborative coding | S11Acquired | 0 | SeedAug 2011 | ||||
 Eyetracking using webcams. | S10Acquired | 0 | SeedJun 2010 |
Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.
Each company is matched to Crustdata by its website. Crustdata adds team size and its change over 6 and 12 months, open roles from job postings, reported funding, and founders' past employers.
Hiring the most counts distinct roles posted in the last 60 days. Growth needs 10+ people today, shrinking 20+ a year ago, so tiny teams do not top the lists. Rebuilt every week.
The numbers on this page come from three Crustdata API calls. Crustdata tags 5,000+ companies with Y Combinator as an investor; swap the filter for any investor, industry or headcount range and track your own list, with founders' work emails one call away.
# 1. every company with Y Combinator as an investor curl https://api.crustdata.com/company/search \ -H "authorization: Bearer $CRUSTDATA_API_KEY" \ -H "x-api-version: 2025-11-01" \ -d '{ "filters": { "field": "funding.investors", "type": "in", "value": ["Y Combinator"] }, "fields": ["basic_info.name", "headcount.total", "headcount.growth_percent", "funding.total_investment_usd"], "limit": 100 }' # 2. open listings per company, last 60 days (limit 0 = counts only) curl https://api.crustdata.com/job/search \ -H "authorization: Bearer $CRUSTDATA_API_KEY" \ -H "x-api-version: 2025-11-01" \ -d '{ "filters": { "op": "and", "conditions": [ { "field": "company.basic_info.company_id", "type": "in", "value": [...] }, { "field": "metadata.date_added", "type": "=>", "value": "2026-08-24" } ]}, "limit": 0, "aggregations": [{ "type": "group_by", "field": "company.basic_info.company_id", "agg": "count" }] }' # 3. the same company filter as a weekly watch: POST /watch/company/search
10 Y Combinator companies have a founder who worked at Mozilla; 6 are active.
1 companies posted roles in the last 60 days, led by Human Interest (36 roles). 2 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Deepnote (+29%) and Human Interest (+12%).
No reported rounds after their YC batch in the last 12 months.