Backend
Development

graph TB
          A[Backend]
          A --> B[Node.js]
          A --> C[Python]
          A --> D[SQL]
          A --> E[APIs]
          B --> F[Event Loop]
          B --> G[Express.js]
          C --> H[Django/Flask]
          C --> I[Data Structures]
          D --> J[Queries & Joins]
          D --> K[Optimization]
          E --> L[REST]
          E --> M[GraphQL]

          style A fill:#3b82f6,stroke:#2563eb,stroke-width:0px,color:#fff,rx:10,ry:10
          style B fill:#22c55e,stroke:#16a34a,stroke-width:0px,color:#fff,rx:10,ry:10
          style C fill:#3b82f6,stroke:#2563eb,stroke-width:0px,color:#fff,rx:10,ry:10
          style D fill:#a855f7,stroke:#9333ea,stroke-width:0px,color:#fff,rx:10,ry:10
          style E fill:#ef4444,stroke:#dc2626,stroke-width:0px,color:#fff,rx:10,ry:10
          style F fill:#bbf7d0,stroke:#86efac,stroke-width:0px,color:#166534,rx:8,ry:8
          style G fill:#bbf7d0,stroke:#86efac,stroke-width:0px,color:#166534,rx:8,ry:8
          style H fill:#bfdbfe,stroke:#93c5fd,stroke-width:0px,color:#1e40af,rx:8,ry:8
          style I fill:#bfdbfe,stroke:#93c5fd,stroke-width:0px,color:#1e40af,rx:8,ry:8
          style J fill:#e9d5ff,stroke:#d8b4fe,stroke-width:0px,color:#6b21a8,rx:8,ry:8
          style K fill:#e9d5ff,stroke:#d8b4fe,stroke-width:0px,color:#6b21a8,rx:8,ry:8
          style L fill:#fecaca,stroke:#fca5a5,stroke-width:0px,color:#991b1b,rx:8,ry:8
          style M fill:#fecaca,stroke:#fca5a5,stroke-width:0px,color:#991b1b,rx:8,ry:8