What are source generators used for?
PICTURE THIS: HOW TO EXPLAIN IT
IdeaC#
HowWhat happens inside
Why they askShows real use
Simple meaning
They generate C# at compile time from analyzers.
WHY — C# instead of guessing?
Why interviewers care about C#:
C# questions separate people
who only read docs from people who shipped.
Keep it short, concrete,
and tied to .NET work.
Stay structured
Name the idea, why it exists, then one short example.
Close cleanly
End with when you use it and one common pitfall.
STEPS — What happens step by step?
Before you speak the answer, walk the interviewer through these steps:
- 1They generate C# at
compile time from analyzers.
- 2Popular for JSON serialization
and DI.
- 3They cut reflection costs
when used well.
- 4Give an example
One tiny concrete case you can say aloud.
- 5Common mistake
What juniors usually get wrong.
- 6Close
When you pick this over the alternative.
EXAMPLE — See it in action
Here's a short line you can speak, broken into clear beats:
Say this line
“Popular for JSON serialization and DI.”
Break into beats
PopularforJSONserializationandDI
Speaking order
2987408337471632900
Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.
Key takeaway
They generate C# at compile time from analyzers. Popular for JSON serialization and DI.