ThreadHub

ThreadHub is a decentralized platform for sharing opinions, where users can express their opinions via threads and receive engagements from other users. Picture Twitter, but on the blockchain.

This project is a concept that demonstrates the possibilities that can be built on Polkadot and was submitted for the Encode X Polkadot Hackathon.

Features

Authentication:

Users can connect their polkadot wallets to the platform, to access threads and for signing transactions.

Thread Creation:

Users can create threads by providing a message. A thread is linked to the creator's account and only them can update the message in the thread.

Liking a Thread:

Users can like theirs and other users threads/replies. Likes are linked to an account and are unique, so they cannot be duplicated.

Replying a Thread:

Threads on ThreadHub can be nested, where comments and replies are subthreads and behave exactly like threads, which means they can have subthreads too.

Technical Details

Stack

• Monorepo Workspace with contracts/ and frontend/ directories as packages.
• Package Manager: pnpm
• Smart Contract Development: Rust, ink!, cargo-contract, substrate-contracts-node
• Frontend: Next.js (app-dir), React, TypeScript
  • Contract Interactions: polkadot-js, useInkathon React Hooks & Utility Library
  • Styling: shadcn/ui, tailwindcss
  • Client-side Data Fecthing: swr
  • Linting & Formatting: eslint, prettier, simple-git-hooks, lint-staged
• Type-safe contract generation via typechain-polkadot

Testing Instructions

Pre-requisites:

• Setup Node.js v18+ (recommended via nvm with nvm install 18)
• Install pnpm (recommended via Node.js Corepack or npm i -g pnpm)
• Clone this repository

1. The Frontend

The frontend works out of the box, without a local node running, as the thread_manager contract is pre-deployed on alephzero-testnet. Necessary deployment metadata and addresses are provided under contracts/deployments/.

# Install dependencies (once)
# NOTE: This automatically creates an `.env.local` file
pnpm install

# Start Next.js frontend
pnpm run dev

2. Building & deploying thread_manager on a local node

The contracts/package.json file contains shorthand scripts for building, testing, and deploying the thread_manager . To run these scripts, set contracts/ as the active working directory in your terminal.

Pre-requisites:

• Install Rust via the Substrate Docs (skip the "Compile a Substrate node" section)
• Install cargo contract
• Install substrate-contracts-node

# Build contracts and move artifacts to `contracts/deployments/{contract}/` folders
pnpm run build

# Start local node with persistence (contracts stay deployed after restart)
# NOTE: When using Brave, shields have to be taken down for the UIs
pnpm run node

## IMPORTANT: Open a separate terminal window and keep the node running

# Deploy the contracts on the local node
pnpm run deploy

# Upload the `thread` contract `code_hash` onchain to enabel Cross-Contract calling in the `thread_manager`contract
cargo contract upload --manifest-path src/thread/Cargo.toml --suri //Alice -x

3. Connect the frontend to the local node

Open the frontend/.env.local file and set the NEXT_PUBLIC_DEFAULT_CHAIN variable to development. Then restart the frontend and you should be able to interact with the contracts deployed on your local node.

Environment Variables

All environment variables are imported from process.env in frontend/src/config/environment.ts and re-exported from there. For improved type safety, Always only import environment variables from @/config/environment and never directly from process.env.

Environment Variables	Default Values	Description
NEXT_PUBLIC_DEFAULT_CHAIN *️⃣	️alephzero-testnet	The network (Substrate-based chain) the frontend should connect to by default and what contract deployment artifacts to import.
NEXT_PUBLIC_PRODUCTION_MODE	false	Optional boolean flag to differentiate production environment (e.g. for SEO or Analytics).
NEXT_PUBLIC_URL	http://localhost:3000	Optional string that defines the base URL of the frontend (will be auto-inferred from Vercel environment variables).
NEXT_PUBLIC_SUPPORTED_CHAINS	–	Optional array with network identifers (e.g. ["alephzero-testnet", "shibuya"]) that are supported by the frontend, if the dApp is supposed to be multi-chain.

*️⃣ Required

Important

All supported chain constants can be found here in the scio-labs/use-inkathon repository.