Backend Coding Challenge
Role: Backend Developer
Evaluate practical backend programming skills with algorithm challenges and code structure exercises in a controlled environment.
Sample questions
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As the candidate sees it
Backend Coding Challenge
- 1.Long text
Describe your experience with distributed systems and the main challenges you faced.
Tell us which systems you worked on (architecture, scale, technologies) and your role. Pick one or two concrete challenges, for example data consistency, partial failures, queues and reprocessing, latency or observability, and explain how you solved them and which trade-offs you accepted.
- 2.Code editor
Implement twoSum: return the indices of the two numbers in the array that add up to the target.
Write the function twoSum(nums, target), which takes an array of integers nums and an integer target and returns an array [i, j] with the indices of two different elements that add up to target, with i less than j. function twoSum(nums, target) { // returns [i, j] } twoSum([2, 7, 11, 15], 9); // [0, 1] twoSum([3, 2, 4], 6); // [1, 2] twoSum([3, 3], 6); // [0, 1] twoSum([1, 2, 3], 7); // [] • The array has 0 to 100,000 elements; values may be negative and repeated. • Do not use the same index twice. If there is more than one pair, return any one; if there is none, return []. • Aim for better than O(n²) and state the time and space complexity in a code comment.
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3 more questions in the full template.
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Long text
Describe your experience with distributed systems and the main challenges you faced.
Answer
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