38 Y Combinator companies with a founder who worked at Twitter before.
Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.
| Company | Batch | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
Unlocking the power of biotech with modern software for modern science | S12 | 813 | +3% | +3% | 4 | $412M | Series F$100M, Nov 2021 |
Contact center AI platform. | W18 | 358 | +6% | −15% | 3 | $214M | Series C$125M, Apr 2022 |
Private sector Healthcare.gov. | S12 | 255 | +2% | +3% | 2 | $6.6M | Undisclosed round$6.6M, Feb 2017 |
Marketplace for America's most essential assets | W24 | 230 | +46% | +150% | 2 | $22.8M | Series B$17.8M, Sep 2026 |
Connecting the world by simulating it | W22 | 107 | +1% | +3% | YC | ||
We make EV charging as simple and reliable as LED lights | W19 | 53 | −2% | −15% | 0 | $17M | Series A$15M, Sep 2024 |
Vori is a modern operating system for supermarkets | W20 | 48 | −27% | +7% | YC | $32.1M | Series B$22M, May 2026 |
SDK for scanning and verifying credit cards and photo IDs in mobile… | S19Acquired | 48 | +4% | +12% | 0 | $150K | YC investment$150K, Aug 2019 |
Investment management platform for real estate | W22 | 42 | +11% | +11% | 0 | $4.5M | Seed (before YC)$3.5M, Nov 2021 |
Agentic Marketing Platform | W24 | 29 | +32% | +93% | YC | $20.9M | Series A$18.7M, Jun 2026 |
Hickory turns your employees into experts. | S15Inactive | 26 | 0% | −4% | 0 | $3.3M | Series A$3.2M, Jan 2017 |
Pierre is a new, opinionated, git platform. | W23 | 23 | +53% | +77% | 0 | SeedJan 2025 | |
Online University for Tech Professionals | S21 | 23 | +10% | +10% | 0 | SeedAug 2021 | |
Emails as quick and easy as text messaging. | W16 | 19 | 0% | 0% | YC | $3.2M | YC investment$120K, Mar 2016 |
Software to launch and integrate genetics into clinical care | W22 | 18 | +13% | +38% | YC | $9M | Seed$8.5M, Jan 2023 |
The world's fastest calendar, beautifully designed for remote teams. | S18 | 16 | 0% | −6% | 0 | $6.4M | Seed$4.5M, Nov 2023 |
A marketplace for live, online workshops for professionals | S20Inactive | 12 | 0% | +9% | 0 | SeedAug 2020 | |
The Enablement Layer for Physical AI | S24 | 10 | +11% | +100% | 0 | $750K | Pre-seed$250K, Feb 2025 |
AI-powered meeting notes and automations | W24 | 7 | +17% | +17% | YC | $3M | Seed$2.5M, Nov 2024 |
Open-source AI coworker with memory | S24 | 6 | 0 | $500K | YC investment$500K, Sep 2024 | ||
AI Sales Assistant to increase playbook adoption and win more deals | S22 | 5 | 0% | 0% | YC | $5.7M | Seed$5.2M, Dec 2022 |
List on multiple resale marketplaces | S21Inactive | 5 | 0% | 0% | 0 | SeedSep 2021 | |
Helps teams work effectively with AI coding agents. | W24 | 4 | −50% | −56% | 0 | $500K | YC investment$500K, Feb 2024 |
| S20Acquired | 4 | −20% | −56% | 0 | $11.4M | Undisclosed round$5M, Oct 2023 | |
Managed GPU-accelerated Spark + SQL at 2x speed and half the cost | X25 | 2 | 0 | $500K | YC investment$500K, Jun 2025 | ||
AI to track and analyze public policy | W21 | 2 | 0 | Pre-seedMar 2021 | |||
| S19Acquired | 2 | 0 | |||||
On demand veterinary house calls. | W15Inactive | 2 | 0 | $1.1M | Seed$365K, Sep 2016 | ||
AI Overview Search, as a Service | S23Inactive | 1 | 0 | $500K | YC investment$500K, Sep 2023 | ||
AI-native operating system for analytics teams | W23Inactive | 1 | 0 | $500K | YC investment$500K, Apr 2023 | ||
Bandit ML builds machine learning tools for e-commerce companies. | S20Acquired | 1 | 0 | $1.5M | Pre-seed$1.3M, Sep 2020 | ||
Acquired by Brex. Building digital payments infrastructure. | W19Acquired | 1 | 0 | SeedMar 2019 | |||
Clear Genetics is scaling delivery of Genomic services | W17Acquired | 1 | 0 | $2.5M | Undisclosed round$2.5M, Nov 2019 | ||
SaaS calendar and messaging for SMBs | W17Inactive | 1 | 0 | ||||
| W10Inactive | 1 | 0 | SeedJan 2010 | ||||
India's largest crypto investing paltform | W19 | 165 | 0 | $22.1M | Undisclosed round$12.3M, Aug 2022 | ||
See and control what your agents actually do | F26 | 0 | |||||
The AI-native radiology practice | S26 | 0 |
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
38 Y Combinator companies have a founder who worked at Twitter; 24 are active.
4 companies posted roles in the last 60 days, led by Benchling (4 roles), Observe.AI (3 roles) and HealthSherpa (2 roles). 8 mark themselves as hiring on YC's directory.
By team growth over 6 months (10+ people): Pierre (+53%), Garage (+46%) and JustAI (+32%).
Largest latest rounds in the last 12 months, after their YC batch: Vori ($22M), JustAI ($18.7M) and Garage ($17.8M).