Computer Sciences Challenges
Explore computer science challenges on Ewance to equip yourself with job-relevant skills for a variety of roles. Learn programming techniques and build technical skills with challenges on software development, algorithm design, system architecture, and more.
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- CodeBeginnerNew
Design a Race-Free Cache for a Read-Heavy Service
Implement a thread-safe LRU-bounded cache in Java (or Go — your choice, defend it) with: read-write lock or copy-on-write semantics, get-or-load pattern with single-flight to de…
- Concurrent Data Structures
- Race Conditions
- Single Flight
Concurrent and Parallel Programming - CodeSeniorNew
Build a Lock-Free MPMC Queue for a Trading-Backend Hot Path
Implement Vyukov's bounded MPMC queue in C++20 using atomic operations with explicit memory orderings (relaxed where safe, acquire/release on the enqueue/dequeue handshake). Use…
- Lock Free Algorithms
- Memory Models
- Cpp
Open coursework - CodeIntermediateNew
Apply Software Transactional Memory to a Real-Time Auction Book
Implement two variants of the same auction-book API (best-bid/best-ask lookup, place-order, cancel-order, match-orders): (1) baseline with java.util.concurrent locks + a SkipLis…
- Transactional Memory
- Concurrent Data Structures
- Haskell
Advanced Concurrency and Parallel Computing - CodeIntermediateNew
Tune a Multicore Pipeline with NUMA-Aware Sharding
Receive the current worker (Rust, around 8,000 lines, uses rayon for its parallelism), the host (2-socket AMD EPYC 9354, 64 cores total, 384GB DDR5), and a benchmark query workl…
- Parallel Performance
- Numa
- Rust
Advanced Concurrency and Parallel Computing Develop in-demand professional skills.
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- CodeSeniorNew
Port a CPU Monte-Carlo Simulator to GPU for an Energy Trader
Receive the existing simulator (C++17 + OpenMP, around 5,000 lines), the test book (around 8,000 spread options), and access to an H100 80GB. Port to CUDA: random-number generat…
- Gpu Programming
- Cuda
- Monte Carlo
Advanced Concurrency and Parallel Computing - CodeSeniorNew
Scale an HPC MPI Workload Across a Multi-Node Cluster
Receive the MPI weather model (Fortran 2018 + C, ~22,000 lines), 4 weeks of strong-scaling logs (1 to 256 ranks), and access to AWS ParallelCluster with EFA-enabled c7gn instanc…
- Hpc Programming
- Mpi
- Parallel Performance
Advanced Concurrency and Parallel Computing - CodeIntermediateNew
Build a Custom Kubernetes Operator for a Multi-Tenant SaaS
Receive the current Helm + bash setup, a description of the per-tenant resources to manage, and the cluster details (EKS 1.29, Strimzi for Kafka). Design a TenantPipeline CRD wi…
- Kubernetes Operators
- Crds
- Kubebuilder
Container Orchestration with Kubernetes - CodeBeginnerNew
Tune Autoscaling for a Cost-Sensitive Workload with HPA + KEDA
Receive the service's current Deployment + HorizontalPodAutoscaler config (static 12-20 replicas), 90 days of traffic logs + Kafka-lag metrics, and the SLA (p99 < 250ms, error r…
- Kubernetes
- Autoscaling
- Keda
Container Orchestration with Kubernetes - Browse challenges
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Pricing Strategist
Set the price that captures value without leaving sales on the table. Demand modelling, willingness-to-pay research, and the disciplined experimentation that turns pricing into a competitive advantage.
- CodeIntermediateNew
Migrate Stateful Workloads to StatefulSets with Storage Class Tuning
Receive the current Redis Sentinel topology (3 nodes, ~120GB data), the EBS gp3 baseline performance requirements (3,000 IOPS, 125 MB/s), and the cluster (EKS 1.29 with the EBS …
- Kubernetes
- Statefulsets
- Storage Classes
Container Orchestration with Kubernetes - CodeIntermediateNew
Build a GitOps Rollout Pipeline with ArgoCD Progressive Delivery
Receive the current CI pipeline (GitHub Actions runs kubectl apply against EKS), one representative service (Go API, 8 replicas, 4ms p99 SLO, 0.1 percent error-rate SLO), and ac…
- Kubernetes
- Gitops
- Argocd
Container Orchestration with Kubernetes - CodeSeniorNew
Tune an Intrusion-Detection Rule Pack for Manufacturing PLCs
Work entirely from the five provided materials. Using the packet captures (M1) and the labeled event manifest (M2), characterize normal Modbus/TCP and Ethernet/IP behavior for t…
- Intrusion Detection
- Ics Security
- Suricata
Open coursework - CodeIntermediateNew
Build a Hybrid Recommendation System for an Indie Streaming Catalog
Use the provided 6-month anonymized event log (around 320M play events, 1.4M unique users in the held-out cohort), audio embeddings (256-d), and track metadata. Implement (1) an…
- Recommendation Systems
- Collaborative Filtering
- Content Based Recommendation
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- CodeFoundationalNew
Swap a List Scan for a Min-Heap in the Dispatcher
Working only from the materials provided, your job is to make the courier-selection logic faster and to show, with evidence, that it actually got faster. First, read the de-iden…
- Heap Data Structure
- Complexity Analysis
- Python
Open coursework - CodeBeginnerNew
Choose a Hash Table or Trie for a URL-Shortener Cache
Build two caches that satisfy the contract in the cache specification (provided): one hash table using linear probing and one compressed trie, both enforcing the same two-millio…
- Hash Tables
- Trie Data Structure
- Benchmarking
Open coursework - CodeIntermediateNew
Design a Lock-Free Concurrent Queue for an Event Bus
Implement an MPSC (multi-producer single-consumer) ring-buffer queue in Go using atomic operations only — no mutexes. Prove correctness with the Go race detector across 8 produc…
- Concurrent Data Structures
- Lock Free Programming
- Go
Data Structures - CodeIntermediateNew
Index a Reference Genome with a Suffix Array in Rust
Using the reference-genome FASTA in the provided materials, build an in-memory suffix array (DC3 or SA-IS construction) over the 4-letter DNA alphabet in Rust, then implement co…
- Suffix Arrays
- String Algorithms
- Rust
Open coursework - DesignIntermediateNew
Author a Scrollytelling Story on a Three-Week Ad-Fraud Anomaly
Using the internal investigation report (provided) and the anomaly dataset (provided), design a seven-section scrollytelling narrative and build it as a static web page. Structu…
- Narrative Visualization
- Scrollytelling
- Svelte
Open coursework - CodeIntermediateNew
Build a WCAG 2.2 AA Accessible Chart Component Library
Build a React and TypeScript component library that exports four chart components (bar, line, scatter, heatmap), each rendering the figures in the provided sample analytics data…
- Accessibility
- Wcag 2
- React
Open coursework - CodeSeniorNew
Build and Evaluate an LSM-Tree Storage Engine in Rust
Your analysis task is to complete the engine and produce an evidence-backed comparison of the two compaction strategies. Start from the 'starter-engine' Rust module and finish t…
- Lsm Tree
- Storage Engine
- Rust
Open coursework - CodeIntermediateNew
Tame Lock Contention on a Shared Property-Manager CRM Database
Working only from the four provided materials, produce a fix-and-prove package. Start with the recorded lock snapshots (lock_snapshots) and the environment case file (db_environ…
- Concurrency Control
- Lock Contention
- Postgresql
Open coursework - CodeBeginnerNew
Ship a Production CI/CD Pipeline for a Fitness-Studio CRM Startup
Using the FlexDesk starter service and Dockerfile, the current-deploy case file, and the pipeline requirements spec provided, build a complete continuous integration and continu…
- Ci Cd
- Github Actions
- Container Signing
Open coursework - CodeIntermediateNew
Refactor a Tangled Terraform Repo for a Multi-Account AWS Estate
Working only from the materials provided — the de-identified repository snapshot, the account-and-region inventory, the plan-timing-and-drift readout, and the platform team's in…
- Terraform
- Terragrunt
- Infrastructure As Code
Open coursework - CodeSeniorNew
Harden a Container Supply Chain to SLSA Level 3
Audit the current build and deploy pipeline against the SLSA 1.0 specification. Identify SLSA-3 gaps (typically: provenance generation, hermetic builds, two-person review, signe…
- Supply Chain Security
- Slsa
- Sigstore
Open coursework - CodeFoundationalNew
Design and Verify a 7-Segment Roaster-Console Display Controller
Working only from the materials provided, build and verify the controller. Implement the controller per the signal definitions in the microcontroller interface specification (ic…
- Verilog
- Fpga
- Digital Logic
Open coursework
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From brief to credential, in six steps.
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Browse challenges aligned to your studies.
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Accept the one that fits your goals.
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