Graded in a sandbox
Test code not shown · 35 min suggested
Run tasks with a concurrency limit
Fifty uploads, but only three at a time.
All required tests passed
How to read this: the verdict comes from the required tests. The counts below describe how the code was written. Nothing here shows who typed it. Iterations are the times the tests were run. Versions are distinct versions of the code the tests ran on. Span is the time from first run to save.
- Required tests
- 6 of 6
- passed
- Bonus
- 2 of 2
- passed
- Iterations
- 6
- graded runs
- Versions
- 6
- distinct versions graded
- Span
- 5 min
- first run to save
- Runtime
- 592 ms
- in the sandbox
- Saved
- Nov 10, 2026
How the code arrived
- Run 1, 0s after the first run: added 20 bytes, failed a required test.
- Run 2, 59s after the first run: added 475 bytes, failed a required test.
- Run 3, 2 min after the first run: removed 40 bytes, failed a required test.
- Run 4, 2 min 56s after the first run: added 190 bytes, passed every required test.
- Run 5, 3 min 56s after the first run: added 221 bytes, passed every required test.
- Run 6, 4 min 48s after the first run: added 90 bytes, passed every required test.
- First graded run
- Did not pass every required test.
Questions to ask in the interview
Questions that start with a line number point at the submitted code. The others come from this Challenge and the counts above. Each one asks the candidate to explain the code in their own words.
- Line 21: why wrap this call in Promise.resolve?
- Line 30: which values get past this typeof check?
- How do you start the next task the moment one finishes, rather than after a batch?
- What happens to tasks that are already running when one of them fails?
- How do you keep results in the order of the tasks array?
- How would you change this to collect every failure instead of stopping at the first?
- Your first graded run did not pass everything. What did you change to get it passing?