Design the apps you use every day.
Pick an app, start from what it needs to do, and build its design on a canvas, one step at a time. Then put it under load and fix whatever breaks.
- Free→
Design your own Bitly
URL shortener
Billions of redirects, a few writes, and IDs that never collide.
easy13 steps · ~45 min - Soon
Design your own YouTube
Video platform
Upload, transcode, and stream at every quality.
medium - Soon
Design your own Instagram
Photo feed
Fan-out on write or on read - and the celebrity who breaks both.
medium - Soon
Design your own WhatsApp
Chat app
Messages delivered in order, with ticks, to phones that are often offline.
medium - Soon
Design your own Spotify
Music streaming
Stream any song instantly, to millions, on any network.
medium - Soon
Design your own Google Maps
Route ETA
Routes and arrival times that follow live traffic.
hard - Soon
Design your own Gmail
Email service
Send, receive, search and never lose a message.
medium - Soon
Design your own Google Docs
Collaborative editor
Many people typing in the same document, and nobody's edit lost.
hard - Soon
Design your own Reddit
Ranked feed
Votes pouring in, and a ranking that stays fresh and fair.
medium - Soon
Design your own Discord
Online status
Who's online right now, for a hundred million users.
medium - Soon
Design your own Dropbox
File sync
Keep every device's files in sync, and send only what changed.
medium - Soon
Design your own Swiggy
Delivery dispatch
Pick the right rider for every order, as riders and orders move.
hard - Soon
Design your own BookMyShow
Ticket booking
Hold a seat, take the payment, never sell it twice.
medium - Soon
Design your own Razorpay
Payment system
Money moves exactly once, even when every network call fails.
hard - Soon
Design your own DynamoDB
Key-value store
A Dynamo-style store that stays up when machines die.
hard
Each system is modelled on a well-known product. Names and logos belong to their owners; sys0 isn’t affiliated with any of them.