The Stack

• Package-Manager: pnpm
• Monorepo Tooling: turborepo
• Smart Contract Development: hardhat
  • Deploy & Address-Export: hardhat-deploy
  • Typescript-Types: typechain
• Frontend: next
  • Contract Interactions: wagmi, rainbowkit
  • Styling: chakra-ui
  • Styled Components: twin.macro, emotion
• Misc:
  • Linting & Formatting: eslint, prettier
  • Actions on Git Hooks: husky, lint-staged

Getting Started

# Install pnpm
npm i -g pnpm

# Install dependencies
pnpm install

# Copy & fill environments
# This step is important when connecting frontend to deployment
cp packages/frontend/.env.local.example packages/frontend/.env.local
cp packages/contracts/.env.example packages/contracts/.env

Development

# Generate contract-types, start local hardhat node, and start frontend with turborepo
pnpm contracts:dev


# Only start frontend
pnpm frontend:dev

Technical Specifications

Deployment

• Our contracts and on Polygon

Login

• All logins are done using sign in with Sign in with Ethereum by Spruce
• User will need to sign a message that proves that the user is the owner of the address

Name + Avatar

• By default, user's name is set to the user's ENS name or Unstoppable Domain name
• User's avatar is also retrieve's from either ENS or Unstoppable Domain
• We are able to create a nickname to our contacts and we store this info in a Tableland DB instance that is specific to the user

Chat & Image / File sending

• The underlying messaging protocol is XMTP
• For sending of images or files, the document will be first uploaded to IPFS
• The messaging of a certain format will be passed through XMTP so the receiver end will know to render the message as either an image or a file

Send Tokens and Stream Funds + Notification

• User is able to send tokens (for now, ERC20 or ERC721) to peers via De-chat
• We utilize CovalentHq, to help us determine the token available to send in the users wallet
• We are able to stream funds to recipient at a rate (i.e if we want to pay for an installment) and this is powered by Superfluid
• After sending, the transaction will get picked up by our custom subgraph indexer by TheGraph and it will get included in the message
• Also, the recipient will get a notification by EPNS alerting the recipient of an incoming transfer

Video Streaming

• We are able to perform video calls with the person that we are chatting with
• And this is powered by LivePeer and XMTP
• Using XMTP as an underlying messaging relayer, we are able to pass the playback id between each other
• User A will initiate a stream and pass playback ID A to User B
• User B will receive the playback ID A , create a stream of his own, join the playback ID A, and pass his own playback ID B back to User A.
• User A, once received playback ID B, is able to join the stream created by User B.
• Each user will be initiating a stream while also watching a stream

Paid membership perks

• Dechat also has paid membership features and this is powered by Unlock protocol
• For now, paid members are able to access to a customized theme only for paid members.
• More to be added in the future.