Overview
What this challenge is about.
Implement HyperLogLog in Java, benchmark precision vs memory on billions of ad-bid events, and deliver a Redis migration plan. Earn a verifiable certificate.
The scenario
The DSP (around USD 95M revenue, IAB OpenRTB integration) sells real-time reach reporting as a premium feature — losing it would cost roughly 12 percent of pipeline.
The Brief
What you'll do, and what you'll demonstrate.
Replace exact-cardinality user-counting at 1.2M events/sec with HyperLogLog sketches at under 2 percent relative error and at most 64KB per (campaign, hour) bucket.
Earning criteria — what you'll demonstrate
- Implement HyperLogLog including bias correction for low cardinalities
- Compute and verify the standard relative error of 1.04 / sqrt(2^p)
- Design a merge operation for distributed cardinality across time buckets
- Trade memory vs error in a real streaming pipeline
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Randomized Algorithms
Master · Algorithms
Strong alignment
This challenge maps to Randomized Algorithms at the Master level. It sharpens the same practical skills your coursework expects — but in a real industry context with actual constraints and deliverables.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- Hyperloglog
Apply hyperloglog to solve real industry problems and demonstrate production-level capability.
- Probabilistic Data Structures
Apply probabilistic data structures to solve real industry problems and demonstrate production-level capability.
- Streaming Systems
Apply streaming systems to solve real industry problems and demonstrate production-level capability.
- Java Programming
Apply java programming to solve real industry problems and demonstrate production-level capability.
- Performance Benchmarking
Apply performance benchmarking to solve real industry problems and demonstrate production-level capability.
- Cardinality Estimation
Apply cardinality estimation to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles: