𝗢𝗽𝘁𝗶𝗺𝗶𝘇𝗶𝗻𝗴 𝗥𝗲𝗮𝗹 𝗧𝗶𝗺𝗲 𝗖𝗵𝗮𝘁 𝗔𝗽𝗽𝘀

𝗢𝗽𝘁𝗶𝗺𝗶𝘇𝗶𝗻𝗴 𝗥𝗲𝗮𝗹-𝗧𝗶𝗺𝗲 𝗖𝗵𝗮𝘁 𝗔𝗽𝗽𝘀

Building a chat app is hard. Poor engineering makes apps slow. It drains batteries. It kills databases. Fix this early to avoid high costs later.

Media Assets Decrypting files uses high CPU. We built an LRU cache.

• Stores decrypted data in memory.
• Limits size to 250MB.
• Limits entries to 100.
• Assets load in under 1ms.

Network Requests Multiple components often ask for the same file.

• Use a promise map.
• One request serves all components.
• Use a Set for message IDs to stop duplicates.

UI Rendering Large lists cause typing lag.

• Use React.memo.
• Skip rendering for hidden panels.
• This keeps frames stable.

WebSockets Bulk syncing stalls servers.

• Sync using timestamps.
• Pause for 5ms every 10 messages.
• This keeps the server responsive for others.

The lesson is simple. Performance comes from resource management. Stop wasting CPU and memory. Plan these layers early.

Source: https://dev.to/manas_31/how-to-optimize-a-real-time-chat-application-a-deep-dive-into-our-production-codebase-3i86