Skip to content

Tracks Drills Topics Technologies Tech stacks Skill areas

Tracks Drills Topics

Loading

Aporeon

Technical interview practice, from one developer to another.

About Privacy Terms

Drills

Pick a focused question that fits your time, stack, and interview goal.

How much time do you have?

Show one-drill sessions you can finish now.

Search

Track

Practice style

Level

More filters1

Topic

Technology

Tech stack

Skill area

18 results across 1 active filter

Page 1 of 1

Concept questionEasy~5 min

Async/await does not create a new thread

Clarify the common misconception that await starts work on a new thread, and explain what actually happens for I/O-bound operations.

.NETASP.NET CoreC#

Concept questionMedium~7 min

Async disposal with IAsyncDisposable

Explains when cleanup needs asynchronous I/O, how await using guarantees disposal, and how ownership, exceptions, DI lifetimes, and shutdown affect the design.

.NETASP.NET CoreC#

Practice drill

Concept questionMedium~7 min

CancellationToken in ASP.NET Core

Use CancellationToken to stop wasted work when clients disconnect, timeouts expire, or background operations are being shut down.

.NETASP.NET CoreC#

Code reviewMedium~10 min

Code review: missing CancellationToken

Review async .NET code that does not accept or propagate CancellationToken and explain the practical production risk.

.NETASP.NET CoreC#

Concept questionMedium~7 min

ConfigureAwait(false) in modern .NET

Explain what ConfigureAwait(false) does, why it mattered historically, and how to reason about it in ASP.NET Core and library code.

.NETASP.NET CoreC#

Debugging scenarioHard~12 min

Deadlock risk from locking and awaiting

Explain why awaiting while holding synchronization resources can create deadlocks, contention, or stalled workflows.

.NETASP.NET CoreC#

Debugging scenarioHard~12 min

Diagnose a slow API caused by blocking async calls

Investigate a production API slowdown caused by blocking async calls, thread-pool pressure, and dependency waits.

.NETASP.NET CoreC#

Concept questionEasy~5 min

Explain async/await in C#

Explain async/await as C# syntax over Task-based asynchronous work, with attention to non-blocking I/O and request throughput.

.NETASP.NET CoreC#

Concept questionMedium~7 min

Fire-and-forget task risks in .NET

Explain why starting background work without awaiting or tracking it is risky in ASP.NET Core applications.

.NETASP.NET CoreC#

Concept questionMedium~7 min

How Task.WhenAll handles exceptions

Explain how Task.WhenAll behaves when one or more tasks fail and how to inspect failures safely.

.NETASP.NET CoreC#

Comparison questionMedium~7 min

IEnumerable vs IAsyncEnumerable for streaming

Compare synchronous enumeration with async streaming and explain when IAsyncEnumerable helps with large or delayed data.

.NETASP.NET CoreC#

Debugging scenarioHard~10 min

Prove ThreadPool starvation with counters, stacks, and traces

Combines ThreadPool counters, repeated stack snapshots, and wait-event traces to distinguish blocked workers from CPU or dependency pressure.

.NETASP.NET Core

Debugging scenarioHard~12 min

Sync-over-async deadlock risk

Investigate deadlocks or starvation caused by blocking on async code with Result, Wait, or GetAwaiter().GetResult().

.NETASP.NET CoreC#

Debugging scenarioHard~12 min

Thread pool starvation in .NET APIs

Diagnose thread-pool starvation caused by blocking work, unbounded concurrency, or sync-over-async in .NET APIs.

.NETASP.NET CoreC#

Comparison questionMedium~7 min

Timeout vs cancellation in .NET

Distinguish timeouts from cancellation and explain how to combine them around external calls and request handling.

.NETASP.NET CoreC#

Concept questionMedium~7 min

Using Task.WhenAll for independent I/O

Use Task.WhenAll to run independent asynchronous I/O operations concurrently while handling exceptions, cancellation, and dependency limits.

.NETASP.NET CoreC#

Concept questionMedium~7 min

What happens when an async method awaits?

Explain the async state machine, continuation scheduling, and exception flow when a C# method awaits a Task.

.NETASP.NET CoreC#

Concept questionEasy~5 min

Why async void is risky

Explain why async void is usually dangerous outside event handlers and how exceptions behave differently.

.NETASP.NET CoreC#