High C# Question 76 of 215

How do you implement a custom awaitable?

.NET / C# · Speak this in 60–90 seconds · Faridabad & Delhi NCR

IdeaC#

HowWhat happens inside

Why they askShows real use

You need GetAwaiter returning something with IsCompleted, OnCompleted, and GetResult.

Why interviewers care about C#:

This is a process

question about C#.

Panels listen for order,

trade-offs, and what you would actually do on a .NET project - not buzzwords.

Stay structured

Name the idea, why it exists, then one short example.

Close cleanly

End with when you use it and one common pitfall.

Before you speak the answer, walk the interviewer through these steps:

1
You need GetAwaiter returning
something with IsCompleted, OnCompleted, and GetResult.
2
Why it exists
Rare outside libraries.
3
I use ValueTask when
allocation matters instead of inventing awaitables.
4
Give an example
One tiny concrete case you can say aloud.
5
Common mistake
What juniors usually get wrong.
6
Close
When you pick this over the alternative.

Here's a short line you can speak, broken into clear beats:

Say this line

“Rare outside libraries.”

Break into beats

Rareoutsidelibraries

Speaking order

29874083374

Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.

You need GetAwaiter returning something with IsCompleted, OnCompleted, and GetResult. Rare outside libraries.