DEV Community: Anshita Verma

Lately, I’ve been digging into what actually slows down APIs. Here are a few bottlenecks that changed how I think about performance

Anshita Verma — Thu, 26 Mar 2026 18:22:14 +0000

• It’s not always the database, sometimes it’s how we call it.
Sending multiple small requests instead of batching them adds network overhead.
• Connections are expensive.
Rebuilding them on every request means repeated handshakes that could’ve been avoided with reuse.
• Even logging can slow you down.
Synchronous logs make the system wait after every write.
• Repeated data fetching is often self-inflicted.
If the same response is requested again and again, caching at the right layer can remove unnecessary load.
• Payload size matters more than expected.
Uncompressed JSON responses increase latency, especially at scale.
• Database connections are costly to create.
Without pooling, each request pays the setup cost
• And sometimes it’s just the format.
JSON is convenient, but not always efficient when compared to something like Protobuf

Lately, I’ve been digging into what actually slows down APIs. Here are a few bottlenecks that changed how I think about performance

Anshita Verma — Thu, 26 Mar 2026 18:22:14 +0000

Lately, I’ve been digging into what actually slows down APIs. Here are a few bottlenecks that changed how I think about performance: • It’s not always the database, sometimes it’s how we call it. Sending multiple small requests instead of batching them add

Anshita Verma — Thu, 26 Mar 2026 18:20:54 +0000

When handling large lists, what actually slows things down: the number of elements we render, or when we choose to load more?

Anshita Verma — Wed, 25 Mar 2026 22:31:02 +0000

Turns out, both. But they're separate problems that need separate tools.

Virtual Scroll → manages how much is rendered at once.
Intersection Observer → manages when work gets triggered

Virtual Scroll keeps the DOM lean no matter how large the dataset grows. Intersection Observer watches the viewport and fires logic only when something actually comes into view.

Which one has made a bigger difference in your projects?