Cambiatus frontend

This project uses Vite as the build tool and Elm as the main language.

You must have yarn installed to develop or build.

Local development with backend

To run the frontend against a local Phoenix backend (instead of staging):

Prerequisites: the backend repo must be cloned, migrated, and seeded — see its README.

Step 1 — install dependencies:

yarn install

Step 2 — start the backend (in the backend repo):

mix phx.server

The backend listens on http://localhost:4000.

Step 3 — start the frontend:

USE_SUBDOMAIN=false yarn start

The USE_SUBDOMAIN=false flag switches auth storage from cookies (subdomain-scoped) to localStorage and enables public/env-config.js, which points the app at localhost:4000.

Open http://localhost:3000 in your browser.

Subdomain-based local dev (advanced)

Modern browsers resolve *.localhost to 127.0.0.1 without any /etc/hosts changes. You can access the app at http://cambiatus.staging.localhost:3000 and the frontend will detect the community slug (cambiatus) and environment (staging) from the subdomain automatically. Auth tokens are stored as cookies scoped to .staging.localhost.

Development (against staging backend)

yarn install
yarn start

This connects to https://staging.cambiatus.io by default (no local backend needed).

To update the GraphQL Elm files, run:

yarn generate-graphql

Code Quality

We check JS with StandardJS and Elm with elm-review before the git push using husky. You can also run yarn standard and yarn review at any moment to make sure your code is passing the linters.

You can also use elm-analyse to get even more insights about the code. This package is not included in the repo, you should install it manually:

yarn global add elm-analyse

elm-analyse              # view analyse result in terminal
elm-analyse -p 3001 -s   # show extended analyse in the browser on `localhost:3001`

Build

yarn install
yarn build

Configurations

The app has a layered configuration stack:

• public/env-config.js — runtime config loaded via <script> tag before the app starts. Sets window._env_ with API URLs, feature flags, and keys. In local dev this file points to localhost:4000. On deployed environments (staging, demo, production) this file is replaced server-side with environment-specific values.
• src/scripts/config.js — build-time defaults. When window._env_ is present (i.e. env-config.js loaded), these are overridden by it. When absent (no env-config.js), falls back to hardcoded staging URLs.
• src/elm/Flags.elm — Elm entrypoint for configuration. Receives the resolved config as flags from src/index.js and decodes it into typed values.

Build system

The app uses Vite 2.9 with vite-plugin-elm for Elm compilation. Key notes:

• @sentry/browser is stubbed to a no-op in development (src/scripts/sentry-stub.js) to avoid a var global conflict in its pre-bundled output. Sentry is only initialised in production builds.
• Node.js polyfills (crypto, buffer, stream, util, process) are injected via vite-plugin-node-polyfills for eosjs compatibility.
• The legacy Webpack setup is still present under scripts/ and config/ and can be used via yarn start:webpack if needed.