Data Sciences Challenges
Explore data science challenges on Ewance to build skills employers expect from analysts and ML engineers. Work through challenges on data cleaning, exploratory analysis, modeling, and storytelling with data.
Most Popular
- AnalysisBeginnerNew
Exploit and Remediate Eight Web Flaws on a FinTech Practice Range
Using the eight challenge specifications in the provided challenge specification brief and the representative Rails module in the provided vulnerable application source bundle (…
- Web Security
- OWASP Top 10
- Penetration Testing
Open coursework - CodeBeginnerNew
Implement Authentication and Access Control for a Civic Portal
Receive the current Next.js + Express prototype, the data model (residents, requests, documents, audit log), and the 4 staff roles (resident, clerk, supervisor, auditor) with th…
- Authentication
- Authorization
- Rbac
Introduction to Computer Security - DesignBeginnerNew
Propose a Cryptographic Target State for a Checkout Stack
Working solely from the four supplied materials — the stack architecture case file, the testssl.sh export corpus, the cryptographic configuration specification, and the best-pra…
- Cryptography
- Tls
- Pci Dss
Open coursework - CodeSeniorNew
Build a Kernel-Module Sandbox for an Untrusted Code Service
Receive the current Docker-based sandbox configuration, post-incident reports for both escapes, and the runtime requirements for Python and C++ (compilers, package availability,…
- Sandboxing
- Seccomp Bpf
- Gvisor
Computer Systems Security Practice your coursework on real scenarios.
Every challenge is shaped from real-world context — not generic exercises. The work mirrors what your degree prepares you for.
Why Ewance
- DesignSeniorNew
Design a Confidential-Computing Architecture for a Genomics Workflow
Receive the workflow description (per-hospital genome BAM files uploaded to S3, processed by a variant-calling pipeline, results returned per-hospital), the partner-hospital leg…
- Confidential Computing
- Remote Attestation
- Secure Architectures
Computer Systems Security - AnalysisIntermediateNew
Run a Red-Team Exercise on a Cloud-Native Microservices Platform
Receive a scoped engagement letter (in-scope: 6 microservices and their CI/CD pipelines; out-of-scope: customer-data exfiltration beyond proof-of-access), the architecture diagr…
- Red Teaming
- Kubernetes Security
- Lateral Movement
Computer Systems Security - AnalysisIntermediateNew
Diagnose a Memory-Hierarchy Bottleneck in a Trading-System Hot Path
Receive the normalizer source (around 4,000 lines of C++17), a replay harness that feeds 30 minutes of recorded market data, and host-machine specifications (Intel Xeon Gold 634…
- Memory Hierarchy
- Performance Profiling
- Perf
Computer Systems and Organization - CodeBeginnerNew
Build an I/O Benchmarking Harness for an Edge Storage Appliance
Receive the appliance specs (4x 7.68TB Gen4 NVMe, ZFS, Linux kernel 5.15), the 3 target workload profiles (4KB random read at QD32, 1MB sequential write at QD8, mixed 70/30 read…
- Io Benchmarking
- Fio
- System Calls
Computer Systems and Organization - Browse challenges
Explore role
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.
- CodeSeniorNew
Vectorize a Risk-Calculation Engine for a Mid-Cap Bank
Receive the existing pricer (C++17, scalar, around 600 lines), 2 weeks of representative input data (around 50M paths), the validation harness, and access to an Intel Ice Lake-S…
- Vectorization
- Avx 512
- Simd
Performance Engineering of Software Systems - CodeSeniorNew
Cache-Optimize a Graph-Analytics Kernel for a Social Platform
Receive the existing kernel (C++ + OpenMP, around 1,200 lines), the 1.8B-edge graph (CSR format, around 14GB), and target hardware (dual-socket AMD EPYC 9354, 384GB DDR5, 256MB …
- Cache Optimization
- Graph Algorithms
- Memory Hierarchy
Performance Engineering of Software Systems - CodeBeginnerNew
Build a Bounded Concurrent Queue for a Microservice Worker Pool
Implement a bounded concurrent queue in Go (no third-party queue libraries; standard library + sync primitives only) that supports: Put(item) blocks when full, TryPut(item, time…
- Concurrent Data Structures
- Mutex And Condvar
- Go
Concurrent and Parallel Programming - CodeFoundationalNew
Parallelize an Image-Processing Pipeline with Data Parallelism
Your analysis task is to take the serial pipeline module and its configuration (provided as 'serial-pipeline-module'), run it against the representative image batch described in…
- Data Parallelism
- Python
- Multiprocessing
Open coursework 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
- CodeBeginnerNew
Implement Async Message-Passing for an IoT Gateway
Receive the current gateway source (Python 3.11, single-threaded paho-mqtt client + a serial HTTP forwarder, ~1,100 lines), a sensor-simulator that fans out 500 mock sensors at …
- Async Programming
- Message Passing
- Asyncio
Concurrent and Parallel Programming - 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
Advanced Concurrency and Parallel Computing - 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 - DesignIntermediateNew
Design Multi-Tenant Network Policies with Calico Tier Enforcement
Receive the cluster topology (120 customer namespaces + 4 platform namespaces), the application traffic patterns (frontend talks to backend talks to its tenant's database), and …
- Kubernetes
- Network Policy
- Calico
Container Orchestration with Kubernetes - 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 - AnalysisIntermediateNew
Mine Basket History to Justify Grocery Shelf-Adjacency Changes
Work only from the materials provided. Use the basket transactions extract to mine frequent itemsets with FP-growth, tuning the minimum support level separately for the food, ho…
- Frequent Itemset Mining
- Fp Growth
- Spark
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
Data Mining and Information Retrieval - AnalysisBeginnerNew
Re-segment a SaaS Customer Base by How Accounts Actually Use the Product
Using the provided usage signals dataset, engineer features that capture how deeply and how often accounts use the product (not just raw volume), standardize them, and run at le…
- Clustering
- K Means
- Hdbscan
Open coursework - ResearchBeginnerNew
Research Roadmap for Meridian DSP's Bid-Matching Pipeline
Using the VP of Machine Learning's context memo (vp-brief) and the pipeline case file (pipeline-case-file) to ground every recommendation in Meridian's actual system, assemble a…
- Information Retrieval
- Learning To Rank
- Research Synthesis
Open coursework - 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
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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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