tl;dr: the official Y Combinator startup directory lists 23 Fall 2026 companies as of august 27 2026. the 31 below are the whole YC F26 batch so far: the 8 at the top are not on the directory yet, the 23 after them are, with the founder and company handles YC's page does not always give you. three of them were on frontrun before YC listed them, by 77, 71 and 28 days.
the YC directory is published, not live
there is a gap between being in a Y Combinator batch and being in the Y Combinator directory.
a founder gets in, moves, starts building and hiring. the directory entry arrives later, on YC's schedule. in between there is a real company with no public record: no listing, no press, often no launch. that window is the only time an investor can reach a YC founder before every other investor has the same list.
we did this once already for the summer batch. this is the fall batch, as of august 27 2026: 23 on the directory, 8 not yet.
every entry below carries the date frontrun first flagged it, where we have one. the three at the bottom are the receipts: companies the graph had before the directory did.
part 1: not in the directory yet
1. Mirrors: staging environments for AI agents
Mirrors (@runmirrors) · 6 followers · flagged august 19
"the staging environment your agents never had." it rebuilds the systems your agents call, then replays real sessions against the copy to catch regressions before a user does. plugs into LangChain, LangGraph and Claude.
founder: @ai_singhal
2. Vexo: a health ring with a mic
Vexo (@vexoring) · 15 followers · flagged august 22
"the world's first health ring that listens." heart rate, HRV, blood oxygen, respiratory rate, skin temperature, sleep and activity measured every second, plus double-tap voice control and silent haptics.
founder: @vikramnarra13
3. Summer Engine: the AI game engine
Summer Engine (@SummerEngineCom) · 44 followers · flagged august 19
build real 2D and 3D games by talking to it, export to Steam, desktop, mobile and web. the CLI connects Claude Code, Cursor, Codex and Gemini to an actual engine. "making it as fun to make games as it is to play them."
founder: @mathiasheide
4. River: the AI desktop
River (@riverworkspace) · 72 followers · flagged august 23
"collaborate with AI across docs, sheets, and slides, with the full context of your work. it reads your real files and writes straight into them." the model sits inside the project with tools for research, code execution and app automation.
founder: @ChandlerSupple
5. Kailash Labs: a factory for small vision models
Kailash Labs (@kailashlabs) · 132 followers · flagged august 19
"convert the world's videos into structured data that machines can reason over." small, grounded video-understanding models you can adapt to a downstream task with very little data.
founder: Shubham Sharma
6. Fenn: the group chat that makes plans happen
Fenn · founder @nal_uh · flagged august 21
consumer. finds the date that works for everyone, keeps the details in one place, follows up with the people who went quiet, puts the plan on a map. founder is ex Apple, Zenly and Life360.
7. Asakana: a 24/7 order agent for food distributors
Asakana · founder @asa_sakana_fish · flagged august 22
listens to customer chats and calls, learns the quirks from order history, writes the order into the ERP or the spreadsheet on the rep's behalf. seafood first because it has the messiest ordering in food. founder Yudai Matsuoka: Columbia MBA, McKinsey, yellowtail fisherman, tuna trader at Mitsubishi.
8. EVO HQ: autoresearch for your codebase
EVO HQ (@evo__hq) · 1,112 followers · flagged may 21
hand it a repo, it finds a benchmark, runs the baseline, then fires parallel agents in git worktrees to beat it. open source, 1k+ GitHub stars, 25k+ installs. the earliest flag on this list, 3 months before anyone said F26.
founder: @alokbishoyi97
part 2: in the directory
9. Lightfield: AI for in-house legal teams
Lightfield (@trylightfield) · 3 followers · san francisco
founders: @lukedwagner12 and Luke Mainwaring
10. Degla: the intelligence layer in the sky
Degla (@degla) · 3 followers · boston
"the fully autonomous intelligence layer in the sky." drones.
founder: @azizhanafi04 (MIT CS)
11. Quippy: daily social-skills practice
Quippy (@therealquippy) · 16 followers · added to the directory this week
short, realistic practice conversations, workplace pushback, first dates, with line-by-line feedback and a curriculum that adapts to what you get wrong.
founder: @12lijonathan (CEO, ex head of product at Luvu, ex Duolingo APM)
12. Vorelios: physics simulation, 1000x faster
Vorelios (@vorelios) · 27 followers · san francisco
"AI that simulates physics 1000x faster." toward engineering superintelligence.
founders: @danielmcneil_ (CEO, ex physics at UF) and Krish Kapadia (CTO)
13. Lantern AI: turn your taste into hires
Lantern AI (@LanternAI__) · 23 followers · san francisco
handles everything in recruiting once it learns who you would hire.
founders: @onethomaschan (CEO) and Justin Tang (CTO)
14. Simulithic: simulate any experiment, ship the winner
Simulithic (@simulithic) · 74 followers · san francisco
connects to your analytics, builds a simulated population from real behaviour, predicts the lift of a product change in minutes.
founders: @itsnotryan (CEO) and @klauscodes (CTO, NASA Space Apps winner, prev Ramp and Bree)
15. Qokedas: data for AI science
Qokedas (@Qokedas) · 48 followers · san francisco
buys real measurement data from lab researchers, spectra, assay results, chromatograms, sensor logs, $50 to $2,000 per dataset, to train models on the physical world. "measurement is a better teacher than text."
founders: @wilhelmmlem, Jesper Johansson, Elias Reinfeldt
16. Lambda Robotics: robots that build data centers
Lambda Robotics (@LambdaRobo) · 102 followers · flagged july 2, at 39 followers · san francisco, team of 6
"robotics for AI infrastructure." robots that build and service data centers. 9 tracked accounts followed it before YC listed it.
founders: Chen Peng (CEO), Yim Ying, Liam Zhong (CTO)
17. Capveon: turning infrastructure demand into action
Capveon · founder @flancast90 · san francisco
helps the contractors who build infrastructure win the work.
founders: Finn Lancaster (CEO, prev Harper YC W25, founder of FinnedAI) and Brison Moorhead (COO)
18. Antropi Robotics: autonomous CNC factories
Antropi Robotics · founder @namaangupta · bengaluru
"autonomous CNC factories for faster hardware."
founders: Naman Gupta (CEO) and Shubh Agarwal (CTO)
19. Forward: unifying global private credit
Forward · founder @DarrylLuo · san francisco, team of 5
matches commercial debt advisors with private credit funds by mandate.
founders: @daniellyoon (CEO), Riley Janjis, Darryl Luo (CTO)
20. Simantic: firmware simulation for AI agents
Simantic · founders @shong0504 and @enough_ahnaf · waterloo, team of 4
let the agent run the firmware before it touches the board.
founders: Seungmin Hong (CEO) and Ahnaf Shahriar (CTO)
21. RightNow: model-hardware co-design at scale
RightNow (@rightnowai_co) · 1,109 followers · flagged march 6
a GPU code editor and RunInfra (@runinfrai), the inference platform that auto-optimizes your model. the longest lead on this list: on frontrun 77 days before YC listed it.
founders: @akashi203 (technical, creator of AutoKernel) and @OsamaKakashi (commercial)
22. Veeza AI: an AI travel agent for weak passports
Veeza AI (@useveeza) · 265 followers
"AI travel agent for people with weak passports, starting with visas." pick a destination, upload a passport, answer questions, it prepares the documents and books the appointment, with a human visa expert reviewing every application.
founder: @alymoursy
23. antimattr: a voice-first hardware interface
antimattr (@antimattr_one) · 289 followers · san francisco
"voice-first hardware interface for human-agent interaction." an interface built for memory and voice that works in noisy rooms. backed by YC, WTFund and gener8tor.
founders: @sridipto_ghosh (CEO) and @sirsho29 (CTO)
24. Sentient OS: on-device AI that does your work overnight
Sentient OS · founder @aditya_vellanki · san francisco
"on-device AI that knows your entire life and does your work overnight."
founders: Jesai Tarun (CEO) and Aditya Vellanki (CTO, 18, UMass Amherst)
25. herdr: the open agent runtime
herdr (@herdrdev) · 18,718 followers · flagged may 27 · ankara, solo founder
a background server owns your coding agents' terminal sessions so the work survives closed lids and dropped SSH. Apache 2.0, 25k+ GitHub stars and 340k+ downloads in 4 months. on frontrun 71 days before YC listed it. the biggest account on this list, up from 10.6k to 18.7k followers in august alone.
founder: @cancelik
no X account found, on the directory
26. GodHands: the company knowledge base that updates itself
GodHands · bengaluru · founders: Sai Vamshi Batchu (CEO), Aditya Bommakanti (CTO)
27. Collar: AI for general partners
Collar · singapore · founders: Jamie Yau (CEO), Kazel Koh En Yang (CTO)
28. Hemlock: a force-sensing wristband for training robotic AI
Hemlock · los angeles, solo · founder: Julian Olschwang
29. Covera: the AI-native OS for insurance brokers
Covera · san francisco · submission intake, carrier quoting, claims, collections · founder: Tiphaine Venet
30. Redoubt Insurance: commercial insurance for small businesses
Redoubt Insurance · added to the directory this week · founder: Andre Beukers (Princeton PhD, computational psychology)
31. Talos: predictive maintenance for power infrastructure
Talos · baltimore, team of 3 · added to the directory yesterday
watches critical power equipment and flags a change in behaviour before it becomes an outage.
founders: Amitav Kohli, Himani Musku, Kevin Hwang
three receipts: the graph had them first
that is 31. 8 before the directory, 23 on it, and 3 the social graph had before YC published them:
- RightNow (@rightnowai_co), model-hardware co-design. flagged march 6. listed may 22. 77 days.
- herdr (@herdrdev), the open agent runtime. flagged may 27. listed august 6. 71 days.
- Lambda Robotics (@LambdaRobo), robotics for AI infrastructure. flagged july 2 at 39 followers. listed july 30. 28 days.
lead time is measured from our first flag to the launched_at date on the company's YC directory entry, not to today.
three followers is the whole point
Lightfield and Degla have 3 followers each. Mirrors has 6. Vexo 15, Quippy 16, Lantern 23.
by any audience metric those numbers are nothing, which is exactly why follower count is the wrong thing to watch. a stealth YC founder has no audience by construction. what they have is a small number of people who already know, and those people leave a trace before the founder does.
tracking YC Winter 2027
if you found this page looking for a YC F26 company list, this is the most complete one we know of today, and it will be stale by next week. the directory will add the 8 at the top, and the graph will already have flagged the next batch.
the pipeline runs every day against every incoming Y Combinator batch, so Winter 2027 founders are being flagged right now, at double-digit follower counts, before the Y Combinator startup directory publishes them.
everything above came through the frontrun API and MCP server: track the right accounts across tech and AI, watch who they follow.
the directory will catch up. the social graph was first.
see who is on the list today →
read next: 10 YC S26 startups not in the Y Combinator directory yet · a16z speedrun cohort 007, all 29 companies · startups flagged before they raised
open source deal flow
companies and founders surfaced on frontrun. curated, every week.
