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Computer & Information Sciences Challenges
Real industry-shaped challenges across Computer & Information Sciences. Pick the specific field you're studying, solve an actual brief, and walk away with verified, portable proof recruiters can confirm in one click.
Recommended challenges
- AnalysisBeginnerNew
Pick a NoSQL Store for an Event-Stream Sidecar Cache
Set up identical 3-node clusters of Redis 7, KeyDB, and DragonflyDB on equivalent hardware. Run the team's captured 24-hour workload trace (around 180k ops/second, 80/20 read/wr…
- Nosql
- Redis
- Benchmarking
Introduction to Database Systems - AnalysisSeniorNew
Diagnose and Fix Query-Planner Misestimates in a FinTech Warehouse
For each of the 6 queries, capture EXPLAIN (ANALYZE, BUFFERS) and compare estimated vs actual rows at each node. Identify the misestimate source per query (single-column stats s…
- Query Optimization
- Postgresql Planner
- Extended Statistics
Advanced Database Systems - CodeSeniorNew
Implement an LSM-Tree-Based Storage Engine Prototype
Implement the engine in Rust. Components: WAL, memtable (skip list), SSTables on disk with bloom filters and sparse index, two compaction strategies (size-tiered, leveled). Cove…
- Lsm Tree
- Storage Engine
- Systems Language Proficiency (Go, Rust, C++)
Advanced Database Systems - DesignSeniorNew
Design a Strong-Consistency Distributed Counter Service
Design the service end-to-end: storage (Spanner / CockroachDB / FoundationDB — you choose), counter scheme (sharded counters with periodic reconciliation vs strongly-consistent …
- Distributed Databases
- Consensus
- Strong Consistency
Advanced Database Systems Practice your coursework on real scenarios.
Every challenge is shaped from real industry context — not generic exercises. The work mirrors what your degree prepares you for.
Why Ewance
- AnalysisIntermediateNew
Tune Concurrency Control on a Multi-Tenant OLTP Database
Capture 6 hours of pg_locks + pg_stat_activity snapshots during peak. Identify the top 8 contention hotspots and classify each (row-level conflict, deadlock cycles, FOR UPDATE p…
- Concurrency Control
- Lock Contention
- Postgresql Or Mysql
Advanced Database Systems - ResearchSeniorNew
Compare NewSQL Architectures for a Real-Time Inventory Platform
Study the architecture papers and documentation for CockroachDB (its Spanner-inspired multi-active design), TiDB (Raft + multi-Raft + TiKV + TiDB SQL layer), and Spanner (TrueTi…
- Newsql
- Distributed Databases
- Raft
Advanced Database Systems - AnalysisIntermediateNew
Tune Consistency Levels for a Global Ride-Hailing Platform
Receive an anonymized topology export (3 regions, RF=3 per region) plus 7 days of query traces tagged by class. Reproduce the matching anomaly in a Kubernetes-based test cluster…
- Consistency Models
- Cassandra
- Distributed Tracing
Distributed Systems - CodeSeniorNew
Implement Raft Consensus for a Self-Hosted Feature-Flag Service
Implement the core Raft algorithm (leader election, log replication, snapshotting) from the original Ongaro & Ousterhout paper. Use an embedded key-value store (BoltDB or sled) …
- Raft Consensus
- Go Programming
- Grpc
Distributed Systems - Browse challenges
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Marketing Analyst
Plan and measure campaigns that grow the business. Funnel analytics, attribution, segmentation, and the rigorous measurement that lets marketing defend its budget at the leadership table.
- AnalysisSeniorNew
Diagnose Clock Skew in a HFT Order Matching System
Receive anonymized PTP grandmaster + slave logs (nanosecond resolution, 30 days, 3 cabinets) plus a synthetic order-flow generator. Identify the drift pattern (likely candidate:…
- Logical Clocks
- Ptp Time Sync
- Cpp Programming
Distributed Systems - DesignIntermediateNew
Migrate a Monolithic Database to a Sharded Topology
Analyze schema (32 tables) + query workload (anonymized 7-day pg_stat_statements export) to identify the right shard key per table. Most tables shard on user_id; identify the 4-…
- Database Sharding
- Postgresql Or Mysql
- Vitess
Distributed Systems - DesignIntermediateNew
Design a Geo-Distributed Storage Layer for an EdTech
Map the access patterns (90 percent reads from the country of origin, 10 percent cross-country via teacher reviewers). Design region routing using a metadata service backed by a…
- Geo Distribution
- Data Residency
- Cockroachdb
Distributed Systems - CodeIntermediateNew
Parallelize a CFD Solver with MPI Across 256 Cores
Profile the serial solver to identify the hot loops (likely: pressure-Poisson solve, advection step, BC update). Decompose the domain via 2D block-structured partitioning. Imple…
- Mpi
- Cpp Programming
- Domain Decomposition
High-Performance and Scientific Computing Build a verifiable portfolio.
Submissions become evidence. Reviewers with shipping experience score against a rubric; the result becomes a credential anyone can verify.
Why Ewance
- CodeIntermediateNew
Port a Monte Carlo Engine to CUDA for an Asset Manager
Profile the CPU MC engine to identify the kernel candidates: path generation (Brownian motion + correlated factors), payoff evaluation, aggregation. Port to CUDA: use cuRAND for…
- Cuda
- Monte Carlo
- Gpu Programming
High-Performance and Scientific Computing - AnalysisIntermediateNew
Tune OpenMP Performance on a Memory-Bound Genomics Pipeline
Profile the existing pipeline at 1, 4, 8, 16, 32, 48, 64 threads using Intel VTune + Linux perf. Identify the bottlenecks (likely candidates: NUMA-unaware memory allocation, fal…
- Openmp
- Numa Awareness
- False Sharing
High-Performance and Scientific Computing - DesignIntermediateNew
Design Parallel I/O for a Climate-Simulation Data Pipeline
Analyze the current I/O pattern: each MPI rank writes its own file via serial HDF5 (the classic anti-pattern). Design a single shared file using parallel HDF5 + MPI-IO with coll…
- Mpi Io
- Parallel Hdf5
- Lustre Filesystem
High-Performance and Scientific Computing - AnalysisIntermediateNew
Build a Performance Model for a Molecular-Dynamics Job
Build an analytical performance model covering: compute time per step (function of atom count + cutoff + interaction type), inter-rank communication cost (function of decomposit…
- Performance Modeling
- Gromacs
- Benchmark Design
High-Performance and Scientific Computing - CodeBeginnerNew
Build a Multi-Level Feedback Queue Scheduler in xv6
Fork the xv6-riscv repository and implement MLFQ in proc.c with 3 priority queues, per-queue time slices (10ms / 20ms / 40ms), priority demotion on slice exhaustion, and a 100ms…
- Operating Systems
- Scheduling
- C Programming
Operating Systems - AnalysisBeginnerNew
Diagnose a Deadlock in a Multi-Threaded File Indexer
Clone the indexer repo (provided), set up reproduction with thread-sanitizer and helgrind, and produce a deterministic deadlock test case in under 5 minutes of runtime. Diagnose…
- Synchronization
- Deadlock Analysis
- C Programming
Operating Systems - AnalysisIntermediateNew
Design a Custom Page-Replacement Policy for a Tier-1 Cloud Provider Simulator
Use the provided simulator (Python harness wrapping a C++ page-cache model) and the team's 3 anonymized workload traces (web-cache, key-value store, batch analytics). Implement …
- Memory Management
- Page Replacement
- Benchmarking
Operating Systems - CodeIntermediateNew
Build a User-Space File System with FUSE for a Storage Startup
Build a FUSE driver (your choice of Rust + fuser crate or Go + bazil/fuse) that proxies POSIX operations to the startup's existing S3-compatible REST API (mock provided). Suppor…
- File Systems
- Fuse
- Rust Programming
Operating Systems - AnalysisBeginnerNew
Audit a Linux Distribution for Setuid Binary Risk
Mount the provided base image (Ubuntu 22.04 LTS derivative) and inventory all setuid + setgid binaries. For each, classify into 4 buckets: legitimately needed, replaceable with …
- Os Security
- Linux Administration
- Setuid Analysis
Operating Systems - CodeSeniorNew
Port a Microkernel IPC Mechanism to a New Architecture
Fork the project repository and port the synchronous IPC fast path to RISC-V (RV64GC). Preserve the existing fast-path invariants: register-only message passing for messages und…
- Microkernels
- Ipc
- Risc V
Advanced Operating Systems - CodeSeniorNew
Build a Unikernel for a Privacy-Focused VPN Provider
Choose either MirageOS or Unikraft as the unikernel framework. Build an image running a minimal WireGuard data plane (existing OCaml or Rust WireGuard reference implementation i…
- Unikernels
- Virtualization
- Wireguard
Advanced Operating Systems - DesignSeniorNew
Design an OS-Level Side-Channel Mitigation for a Multi-Tenant Cloud
Read 3 canonical cache-side-channel papers (provided). For each attack: characterize the threat model, the required attacker capabilities, and the OS-level invariant that, if he…
- Os Security
- Side Channels
- Virtualization
Advanced Operating Systems
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From brief to credential, in six steps.
Step 01
Browse challenges aligned to your studies.
Step 02
Accept the one that fits your goals.
Step 03
Work through it with AI Copilot guidance.
Step 04
Submit for structured evaluation.
Step 05
Earn a verified credential.
Step 06
Add it to LinkedIn with one click.
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