Public viewer
The journey of every round
Every round-trip in the corpus is public. Open one to see the prompt, the zero-point index, the baseline response, the enhanced response, and how each grader read the difference. Leave a comment if a grader's reading lands — or doesn't.
Use Memory<byte> and ArrayPool<byte>.Shared to read a file in 4KB chunks without re-allocating buffers per iteration. No async.
Demonstrate await on Task.Delay inside an async method that returns Task<int>. Show calling it twice in parallel via Task.WhenAll.
Use DateTime.UtcNow plus a TimeSpan to compute a deadline 7 business days from now, skipping Saturday and Sunday.
Write a Regex that matches IPv4 addresses in the form '1.2.3.4' (each octet 0–255). Use Regex.Match on a sample string.
Use StringBuilder to format a CSV row from an array of object?, treating null as empty. Escape any commas in values by wrapping in quotes.
Write a ReadOnlySpan<byte>-based UTF-8 BOM check: return true if the span starts with the bytes 0xEF 0xBB 0xBF.
Write a switch expression that maps an int status code (200, 301, 404, 500) to a string label. Use the 'when' clause for the 5xx range.
Configure Serilog with a console sink and a file sink that rolls daily. Include a custom enricher (ILogEventEnricher) that adds the machine name to every log event.
Define a gRPC service in protobuf with one bidirectional streaming method that echoes back messages with a server-side timestamp. Show the server-side service implementation.
Build a SignalR Hub that lets clients subscribe to a 'price-tick' channel and broadcasts ticks to all subscribers on a one-second timer.
Write a FluentValidation AbstractValidator<T> for a 'RegisterUser' command: email (valid format), password (≥ 8 chars, has digit and symbol), age (18+).
Implement an IHealthCheck that returns Healthy when a TCP socket on a remote host responds within 500ms, and Unhealthy otherwise.
Write a Regex that matches IPv4 addresses in the form '1.2.3.4' (each octet 0–255). Use Regex.Match on a sample string.
Write a ReadOnlySpan<byte>-based UTF-8 BOM check: return true if the span starts with the bytes 0xEF 0xBB 0xBF.
Build a SignalR Hub that lets clients subscribe to a 'price-tick' channel and broadcasts ticks to all subscribers on a one-second timer.
Write a SQL query that returns the top 5 customers by total spend in 2025.
What is the least common multiple of 4, 6, and 9?
What is the area of a circle with radius 5? Use pi approximately 3.14159.
Simplify the expression 3x squared times 4x cubed.
What is the greatest common divisor of 36 and 48?
Calculate 25 squared minus 24 squared.
What is 2 cubed times 3 squared?
What is the perimeter of a triangle with sides 5, 7, and 10?
Solve: 2x squared minus 8 equals 0