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+# Condenser - Claude Code Project Guide
+
+## Project Overview
+
+Condenser is the React.js web interface for Hive.blog, a blockchain-based social media platform powered by the Hive blockchain. It's a full-stack application combining server-side rendering (SSR) with Koa.js and client-side React rendering.
+
+## Tech Stack
+
+- **Frontend**: React 18.1, Redux 3.7 + redux-saga, Immutable.js
+- **Server**: Koa.js 2.x (Node.js SSR)
+- **Styling**: SCSS, Material-UI v5, Emotion (CSS-in-JS)
+- **Blockchain**: @hiveio/hive-js, hive-auth-client, hivesigner
+- **Build**: Webpack 5, Babel 7 (no TypeScript)
+- **Testing**: Jest 29, @testing-library/react, Enzyme
+- **Linting**: ESLint (Airbnb config), Prettier
+
+## Directory Structure
+
+```
+src/
+├── app/                    # React frontend application
+│   ├── Main.js             # Client entry point (webpack entry)
+│   ├── components/         # React components
+│   │   ├── elements/       # Reusable UI elements
+│   │   ├── cards/          # Card components
+│   │   ├── modules/        # Feature modules
+│   │   └── pages/          # Page components
+│   ├── redux/              # Redux reducers and sagas
+│   ├── utils/              # Utility functions
+│   ├── locales/            # i18n translation files
+│   └── assets/             # Stylesheets
+├── server/                 # Koa.js server for SSR
+│   ├── index.js            # Server entry point
+│   └── api/                # Server API endpoints
+├── shared/                 # Shared client/server code
+│   └── api_client/         # Blockchain API client
+└── hooks/                  # Custom React hooks
+
+webpack/                    # Webpack configurations
+config/                     # Environment configs (default.json, production.json)
+```
+
+## Development Commands
+
+```bash
+# Development
+yarn start                  # Run dev server (~60s startup)
+yarn debug                  # Dev with Node inspector
+
+# Build & Production
+yarn build                  # Build for production
+yarn production             # Run production server
+
+# Code Quality
+yarn fmt                    # Format with Prettier
+yarn eslint                 # Lint changed files
+yarn eslint:fix             # Auto-fix lint issues
+yarn test                   # Run Jest tests
+
+# Docker
+./run.sh start dev          # Start dev environment
+./run.sh start prod         # Start production
+./run.sh stop <env>         # Stop environment
+```
+
+## Key Files
+
+- **Client Entry**: `src/app/Main.js`
+- **Server Entry**: `src/server/index.js`
+- **Config**: `config/default.json`, `config/custom-environment-variables.json`
+- **Webpack**: `webpack/base.config.js`, `webpack/dev.config.js`, `webpack/prod.config.js`
+
+## Coding Conventions
+
+- **File Naming**: CamelCase for .js/.jsx files
+- **CSS**: BEM methodology with SCSS (e.g., `Header`, `Header__menu-item`, `Header__menu-item--selected`)
+- **Formatting**: 4-space indent, 120-char line width, single quotes, trailing commas (es5)
+- **Components**: Functional components with hooks, redux-saga for side effects
+- **Environment Variables**: Use `SDC_` prefix (e.g., `SDC_SESSION_SECRETKEY`)
+
+## CI/CD Notes
+
+**Stages**: test → build → deploy
+
+**Jobs**:
+- `run-unit-tests`: Jest with coverage
+- `run-eslint`: Lint all src/
+- `build-review-app`: Deploy MR preview
+- `deploy-staging`: Deploy develop branch
+
+**Protected Branch**: `develop` - requires MR with passing pipeline
+
+**Review Apps**: Deployed to `review.*.condenser.engrave.dev` on MRs