Sign-In with Ethereum for Discourse

A Discourse plugin that lets users authenticate with their Ethereum wallet using the Sign-In with Ethereum (SIWE) standard. Injected wallets (MetaMask, Safe, etc.) work out of the box. ENS names and avatars are resolved server-side when an RPC endpoint is configured.

Requirements

• A Discourse forum that is self-hosted or hosted with a provider that supports third-party plugins, like Communiteq.

Installation

Access your container's app.yml file:

cd /var/discourse
nano containers/app.yml

Add the plugin's repository URL to the after_code hook:

hooks:
  after_code:
    - exec:
      cd: $home/plugins
      cmd:
        - sudo -E -u discourse git clone https://github.com/discourse/docker_manager.git
        - sudo -E -u discourse git clone https://github.com/signinwithethereum/discourse-siwe-auth.git # <-- added

Follow the existing format of the docker_manager.git line; if it does not contain sudo -E -u discourse then use git clone https://github.com/signinwithethereum/discourse-siwe-auth.git instead.

Rebuild the container:

cd /var/discourse
./launcher rebuild app

Configuration

After installation, find the plugin under Admin > Plugins and make sure it is enabled:

Click Settings to configure the plugin:

From here you can customize the sign-in statement and optionally add a WalletConnect / Reown project ID. Without a project ID, only injected wallets (MetaMask, Safe, etc.) are available.

Settings

Setting	Description
Discourse siwe enabled	Enable or disable Sign-In with Ethereum authentication.
Siwe ethereum rpc url	Optional. An Ethereum JSON-RPC endpoint used for ENS name/avatar resolution and EIP-1271 signature verification (required for smart contract wallets like SAFE). A dedicated provider (Alchemy, Infura) is recommended. Example: https://mainnet.infura.io/v3/YOUR_KEY.
Siwe project ID	Optional. A WalletConnect / Reown project ID. Without it, only injected wallets (MetaMask, Safe, etc.) are available. To enable WalletConnect, create a free project ID at dashboard.reown.com.
Siwe statement	The human-readable statement shown in the SIWE message. Defaults to "Sign in with Ethereum".

Tests

The plugin includes unit and integration tests for ENS resolution helpers and EIP-6492 smart wallet signature verification.

Unit tests (no network needed)

ruby test/ens_unit_test.rb
ruby test/smart_wallet_unit_test.rb

Integration tests (require an Ethereum RPC endpoint)

ruby test/ens_integration_test.rb
ruby test/smart_wallet_integration_test.rb

By default, integration tests use a public RPC. Set RPC_URL for a dedicated provider:

RPC_URL=https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY ruby test/smart_wallet_integration_test.rb

Run all tests

for f in test/*_test.rb; do ruby "$f"; done

How it works

When a user clicks the Ethereum login button, the plugin opens a dedicated authentication. The user connects their wallet, signs a SIWE message, and is authenticated via an OmniAuth strategy on the server side.

After first sign-in, users are asked to associate an email address with their account. If an RPC URL is configured and the connected address has an ENS name, the name is resolved and verified server-side and suggested as the default username. ENS avatars are fetched via the ENS metadata service and used as the profile photo.

Alternatively, existing users can connect their Ethereum accounts via their profile settings.