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
Rescue a Stalling Scrum Team at a Series-B HealthTech
Review 8 hours of recorded ceremonies and 3 sprints of Jira data (story sizing, carry-over rate, cycle time per story, blocker tags). Diagnose the top 3 root causes (likely cand…
- Agile / Scrum Ceremonies
- Agile Metrics
- Retrospectives
Agile Methods and Practices - AnalysisIntermediateNew
Continuous Delivery Maturity Audit for a Fintech Backend
Collect 8 weeks of deployment data (lead time for changes, deployment frequency, change-failure rate, mean time to restore) per team using their GitHub Actions + Jira + PagerDut…
- Continuous Delivery
- Dora Metrics
- Ci Cd
Agile Methods and Practices - CodeFoundationalNew
Optimize a Slow Search Function for a Recipe Marketplace
Receive the current Python function (nested loop over (recipe_title, ingredient_list) pairs), the 400k-row dataset (CSV), and 20 representative queries. Step 1: write up the cur…
- Algorithm Analysis
- Big O
- Functions & Data Structures
Algorithm Design and Analysis - CodeBeginnerNew
Greedy Algorithm for Delivery-Slot Assignment
Receive 14 days of order data (around 4,800 orders) with timestamps, addresses (already geocoded), and slot preferences, plus rider rosters with shift starts, ends, and max work…
- Greedy Algorithms
- Algorithm Analysis
- Python Or Javascript
Algorithm Design and Analysis 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
- CodeIntermediateNew
Dynamic Programming for an IoT Battery Allocator
Read the device spec (32 KB RAM, 200 mAh daily budget, 9 sensing modes with mAh cost and farmer-value scores) and formulate the daily allocation as a 0/1 knapsack DP (dynamic pr…
- Dynamic Programming
- Algorithm Analysis
- C Programming
Algorithm Design and Analysis - CodeBeginnerNew
Shortest-Path Routing for a Bike-Share Operator
Receive the graph (nodes with lat/lon/elevation, edges with length and slope) and 50 origin-destination test pairs. Implement Dijkstra's algorithm with a custom edge-weight func…
- Graph Algorithms
- Dijkstra
- Algorithm Analysis
Algorithm Design and Analysis - CodeSeniorNew
Min-Cost Max-Flow for Cloud Workload Placement
Receive 30 days of anonymized placement requests (workload CPU/memory shape, affinity rules), zone capacity per day, and cross-zone bandwidth costs. Model the placement as a min…
- Network Flows
- Algorithm Analysis
- Graph Algorithms
Advanced Algorithms - ResearchSeniorNew
Approximation Algorithm for an SRE On-Call Roster
Formulate the roster as a constrained multi-week assignment problem. Show it's NP-hard via reduction. Design a deterministic constant-factor approximation (likely candidate: an …
- Approximation Algorithms
- Linear Programming
- Np Completeness
Advanced Algorithms - Browse challenges
Explore role
Product Manager
Ship product that solves real user problems. Combine user research, prototyping, and stakeholder alignment to turn ambiguous briefs into measurable wins — the role at the centre of modern software teams.
- AnalysisIntermediateNew
Amortized-Analysis Investigation of a Production Cache
Read the C++ cache source (around 1,800 lines, custom open-addressing with periodic resize-and-rehash). Perform amortized analysis using all three methods (aggregate, accounting…
- Amortized Analysis
- Functions & Data Structures
- Algorithm Analysis
Advanced Algorithms - CodeIntermediateNew
Randomized Sketch Algorithm for Stream Cardinality
Read the HLL paper (Flajolet et al., 2007) and a sample of 30 minutes of customer trace IDs (around 80M events). Implement HLL from scratch in Go (no library imports). Run bench…
- Randomized Algorithms
- Sketching
- Algorithm Analysis
Advanced Algorithms - AnalysisIntermediateNew
Spectral Clustering for Customer Segmentation at a SaaS
Receive a 12,000 customer × 220 feature usage matrix (counts per feature per week, averaged over 12 weeks). Construct a similarity graph (k-nearest-neighbors with k=15, Gaussian…
- Spectral Methods
- Linear Algebra
- Algorithm Analysis
Advanced Algorithms - CodeIntermediateNew
Add Idempotency Keys to a Payment Webhook System
Read the current Go webhook-sender code and 30 days of duplicate-delivery incident logs. Design the idempotency scheme: server-generated key per event (UUID v7 — time-ordered), …
- REST API Design
- Idempotency
- Webhooks
API Design and GraphQL 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
Migrate an Internal Service from REST to gRPC
Receive the existing OpenAPI spec, the Go service code, and 7 days of traffic data. Pick the top 2 RPS-by-method endpoints and design Protocol Buffers (protobuf) message + servi…
- Grpc
- Protobuf
- REST API Design
API Design and GraphQL - AnalysisBeginnerNew
Developer-Experience Audit of a Public API
Walk through the existing public API as a first-time developer using only the public docs, OpenAPI spec, SDKs (Python + JavaScript), and example repos. Run the first-hour test 3…
- Developer Experience
- REST API Design
- Audit Grade Documentation
API Design and GraphQL - CodeIntermediateNew
Implement Authenticated Encryption for a Document Service
Design the envelope-encryption hierarchy: customer Key Encryption Key (KEK) held in AWS KMS (Key Management Service), Data Encryption Keys (DEKs) wrapped per document. Use AES-2…
- Applied Cryptography
- Aead
- Key Management
Applied Cryptography - CodeIntermediateNew
Build a Streaming Pipeline for Real-Time Fraud Detection
Receive 30 days of anonymized card-transaction events (around 240M events total), the team's existing batch features (cardholder behavior summaries), and a pre-trained fraud-sco…
- Stream Processing
- Kafka Event Streaming
- Flink
Big Data and Data-Intensive Systems - DesignIntermediateNew
Migrate a 200TB Data Lake from Parquet to Iceberg
Receive an inventory of the 200TB hot tier (around 1,200 tables, around 38 PB of historical data referenced), the current Spark + Trino read patterns, and 6 months of schema-cha…
- Iceberg
- Parquet
- Data Lake
Big Data and Data-Intensive Systems - AnalysisIntermediateNew
Optimize a Slow Trino Query Over a Petabyte Warehouse
Receive the slow SQL query (around 600 lines), the Trino EXPLAIN ANALYZE output, the underlying Iceberg table schemas (partition specs, sort orders), and 30 days of execution me…
- Trino
- SQL Optimization
- Iceberg
Big Data and Data-Intensive Systems - CodeIntermediateNew
Design a Change-Data-Capture Pipeline for an E-Commerce Reseller
Receive the MySQL schema (220 tables), 7 days of binlog samples, and the data team's freshness + correctness requirements. Design the CDC pipeline: Debezium for MySQL binlog cap…
- Change Data Capture
- Debezium
- Kafka Event Streaming
Big Data and Data-Intensive Systems - CodeIntermediateNew
Build an Indexer for an On-Chain DeFi Analytics Product
Receive the 6 protocols' ABIs + the team's required event coverage spec (around 40 event types). Build a TypeScript indexer using viem + Postgres: subscribe to new blocks via We…
- Blockchain Indexing
- Typescript
- Ethereum
Blockchain and Decentralized Systems Engineering - CodeBeginnerNew
Containerize a Legacy Java Monolith and Deploy to ECS
Receive the Java 8 monolith source (around 320k lines), the current Tomcat + Apache HTTPD config, and 30 days of production traffic logs. Containerize the application (multi-sta…
- Containerization
- Docker
- AWS Or Azure
Cloud Computing - DesignSeniorNew
Multi-Region Active-Active Architecture for a Gaming Backend
Read the current architecture (single-region: ECS + RDS Aurora + Redis + S3) and traffic mix (around 60 percent APAC, 25 percent NA, 15 percent EU). Design a 3-region active-act…
- Multi Region Architecture
- AWS Or Azure
- Terraform
Cloud Computing - DesignIntermediateNew
Build a Multi-Tenant SaaS Foundation on Kubernetes
Design the multi-tenant model: namespace-per-tenant for compute isolation, per-tenant Postgres schemas inside a shared RDS instance for data, per-tenant S3 prefixes with bucket …
- Kubernetes Orchestration
- Multi Tenancy Architecture
- AWS Or Azure
Cloud Computing - CodeIntermediateNew
Build a Self-Service Internal Developer Platform on Backstage
Stand up a Backstage instance (Docker-Compose for local, EKS for prototype hosting). Build 3 software templates: (1) New Go microservice (repo + CI + ECS service + Terraform + b…
- Internal Developer Platform
- Backstage
- Terraform
Cloud Computing
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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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