For people who hate dating apps.
No swiping and no feeds. One match a week, chosen by what you both actually care about.
Try the demo in your browser →
Sign in with the address it fills in and the code 123456. No email is sent.
Sam has deleted three dating apps this year. The swiping, the forty half-finished conversations, the feeling of being one card in someone else's deck. HateD works the other way round: you say what you're like and what matters to you, and once a week you meet one person, chosen for both of you. This is Sam's first week.
It starts with an email address, a university one. HateD only opens to verified university and government addresses, so everyone Sam could meet has done the same. There's no password to make up: a six-digit code arrives, and no match ever sees the address.
Then five questions about Sam, one at a time, on sliders rather than checkboxes: how much shared values shape the day, how social, how driven, how much humor leads, how open to new things. Any of them can be skipped. Then the other side of it: for each of those, what Sam hopes for in someone, and how much it matters. "Don't mind" leaves a trait out of matching altogether.
Two to six photos, a line in Sam's own words and two prompts to answer. A match reads all of it before deciding, but sees the photos only as a blur until both of them have said hello, and "See them as your match will" shows exactly that. Each photo is re-encoded when it's uploaded, which leaves everything hidden in the file behind, location included, and a person checks it before any match sees it.
Home is a candle that burns down over the week. When it goes out, on Sunday at 8 pm, the round closes: everyone taking part is matched at once, nobody gets more than one match, and everyone finds out at the same moment. Sitting a round out is one switch. (The demo can't ask you to wait a week, so it has a button that skips ahead to Sunday.)
Sam's match arrives sealed. Breaking the seal opens Maya's profile: her line, her answers to the prompts, what her questionnaire says about her, and why the two of them fit. Her photos stay blurred. There's nothing to swipe, only "Say hello" or "Not for me".
From the moment the round is published, the two of them have 24 hours to say hello. Sam says it and can put the phone down; the countdown shows how long Maya still has. If the time runs out before both have said it, the match closes quietly, with the same words on both sides, so nobody ever learns who said hello and who didn't. A few hours before it does, whoever hasn't said hello gets a reminder, worded the same whether or not the other person has.
Maya says hello back. Both phones move at the same moment: the two circles meet, the photos come into focus, and the conversation opens.
An empty conversation suggests a few ways in, drawn from Maya's prompts and from what the two of them share. One tap puts it in the message box, and then it's just two people talking, with three dots when the other one is writing.
Every round's match stays in one list, newest first, with the last message and anything unread. When the next week comes, home asks once how it went with Maya: really well, okay, or not for me. Only HateD sees the answer, as a signal for making matches better. In settings Sam can change any answer, choose which notifications to get, sit out rounds, download a copy of everything HateD holds, or delete the account and everything in it.
A round is a stable matching, chosen to be fair. The engine is
packages/core, pure TypeScript with no I/O, in four steps:
- Ranking. Everyone ranks everyone they could meet by their own answers: how alike the two of them are, and how well the other fits what this person hoped for. The two directions are allowed to disagree, which is what leaves room for the last step.
- Two sides. Stable matching needs two sides, and real people don't come in two tidy groups. An orientation-aware split puts people who could match on opposite sides, so nobody is left out for who they are or who they're open to meeting.
- A stable matching. Gale–Shapley pairs everyone so that no two people would both rather be with each other than with the match they got.
- The fairest one. There are usually many stable matchings, and plain
Gale–Shapley returns the one that's best for one side and worst for the
other. HateD moves through the lattice of stable matchings by rotations
and picks the one where the person who does worst does as well as possible
(
min-regret). Every candidate is checked to be stable before it is scored.
flowchart LR
app["App<br/>packages/mobile<br/>Expo: iOS, Android, web"]
api["API<br/>packages/api<br/>Hono"]
db[("Postgres<br/>packages/db<br/>Prisma")]
core["Matching engine<br/>packages/core"]
app -- "REST" --> api
api -. "WebSocket: live updates" .-> app
api <--> db
db -. "NOTIFY" .-> api
api -- "weekly round" --> core
api -- "push" --> expo["Expo push"]
api -- "sign-in codes" --> mail["Email<br/>SMTP or Resend"]
| Package | What it is |
|---|---|
packages/core |
The matching engine: ranking, orientation-aware sides, Gale–Shapley, and the fairness search. |
packages/db |
Everything that touches Postgres: sign-in, profiles, photos, rounds, the chat, live events, reports, and the data export. |
packages/api |
The HTTP and WebSocket API the app talks to, which also runs the weekly round, sends the reminders, and serves a small admin page for reviewing photos and reports. |
packages/mobile |
The app for iOS, Android and the web, with Expo Router, and the browser demo. |
The db, api and mobile packages each have a README with the details; the engine explains itself in its source.
Privacy, by default. The server decides on every request which photos a person may see, and a photo reaches a match only once it's been reviewed. Photos lose their metadata when they're uploaded. Push notifications never carry a message's text. A pass or a report ends a match without telling the other person why, and a match that closes unanswered reads the same to both people. Anyone can download everything HateD holds about them, or delete it all, from settings.
You need Node 22 (see .nvmrc) and Docker.
npm install
docker compose up -d # Postgres
cp packages/db/.env.example packages/db/.env
npm run db:migrate # create the tables
npm run seed -w @hated/db # the institutions and the questionnaire
npm run seed:demo # 24 made-up members to be matched with
npm run api # the API, on port 3000
npm run mobile # the app: scan the QR code with Expo GoWith no email provider configured, the API prints each sign-in code in its
terminal, so you can sign in with any address at demo.example.edu, the demo
members' included. Rounds run on their own on Sundays at 8 pm (Melbourne time,
unless you change it); npm run round -- --status PUBLISHED runs one now.
npm run web -w @hated/mobile opens the app in a browser instead.
New photos wait for a review before a match sees them. Put ADMIN_PASSWORD
(16 characters or more) in packages/api/.env to open the admin page at
http://localhost:3000/admin (user admin), or PHOTO_REVIEW=false to skip
reviews on your own machine.
To check everything:
npm test # db's integration tests need TEST_DATABASE_URL in packages/db/.env
npm run typecheck
npm run lint -w @hated/mobile
npm run demo:export -w @hated/mobile && npm run test:e2e -w @hated/mobile # the demo in a browserThe last line walks a visitor's first weeks through the demo, in Chromium
(npx playwright install chromium in packages/mobile fetches it once). CI
runs all of it on every push and pull request
(.github/workflows/ci.yml).
The demo is the real app, built with
EXPO_PUBLIC_DEMO=1. Instead of calling the API, it talks to a stand-in that
runs in your browser (packages/mobile/src/demo),
with eight made-up people and painted portraits, never photos of real people.
They play their part: one says hello back while you wait, one has already
said it, one never does, and they answer in the chat. Sign in with any
school-style address (one is filled in for you) and the one-time code
123456: no email is sent, and your demo account stays in your browser.
npm run demo serves it locally, with no API or database.
Every push to main that passes CI publishes the demo to GitHub Pages
(.github/workflows/pages.yml).