Business
ESG, Sustainability & Impact Challenges
ESG, Sustainability & Impact challenges put you inside the work of measuring and disclosing how an organization affects the planet and society. You'll build on Climate Basics and ESG Frameworks, run a Materiality Assessment, and carry out GHG Protocol Scope 1 emissions accounting the way sustainability teams actually do.
From there you'll handle the harder edges — GHG Protocol Scope 2 & 3 accounting, CSRD / ISSB Disclosures, transition planning, and air-quality dispersion modeling — backing every claim with ESG data governance and audit-grade documentation, and mapping outcomes to the UN SDGs. Each challenge you solve earns a verified credential you can share with recruiters.
Recommended Challenges
· Audit-grade documentation Clear- DesignIntermediateNew
Build a Scalable-System-Design Spec for a Streaming-Ingest Pipeline
Receive the current architecture (Kafka 3.6, Flink 1.18, ClickHouse 24.x), 4 weeks of production metrics (per-topic throughput, partition skew, Flink operator backpressure, Clic…
- Scalable System Design
- Kafka
- Flink
Open coursework - 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 - 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
Build a Secure-Coding Linter Ruleset for a Backend Team
Using the findings log, study the twelve documented security-review findings and confirm the three repeat patterns. Then build a custom linter ruleset — choose Semgrep or custom…
- Secure Coding
- Static Analysis
- Semgrep
Open coursework Develop in-demand professional skills.
Each challenge names the skills it strengthens. Over time, your profile fills with the competences a hiring manager would actually look for.
Why Ewance
- CodeIntermediateNew
Deploy SDN-Based Network Slicing for a Telco Operator
Receive the current transport architecture (P4-programmable switches, ONOS controller cluster), the 3 customer-class SLAs (consumer: best-effort 50 Mbps; enterprise IoT: 5 Mbps …
- Sdn
- Onos
- Mininet
Advanced Computer Networks - 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
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
Open coursework - DesignIntermediateNew
Design a Versioning Strategy for a Public REST API
Receive the OpenAPI spec for the 14 endpoints, 8 months of partner-support tickets tagged 'breaking-change', and the partner-mix breakdown (which endpoints which partner uses). …
- API Design
- REST
- API Versioning
API Design and GraphQL - Browse challenges
Explore role
Strategy Analyst
Frame the business question, model the options, build the recommendation. From market sizing to competitive analysis, this role is where strategy consulting meets in-house decision-making.
- CodeIntermediateNew
Build and Audit an ERC-20 Vesting Contract for a DeFi Startup
Implement an ERC-20 vesting contract with: per-beneficiary cliff (default 12 months) + linear vesting (default 36 months), revocable allocations (for founders only), pause funct…
- Solidity
- Smart Contracts
- Foundry
Blockchain and Decentralized Systems Engineering - CodeBeginnerNew
GPU Cost Dashboard for an AI Consulting Practice
Pull AWS Cost and Usage Report, GCP billing export, and Lambda Labs invoices into a single Parquet table. Implement a tagging convention (project + client + experiment_id) and a…
- Cloud Cost Attribution
- Etl Pipelines
- Data Modeling
Cloud Computing for Data and ML - 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 - 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 Get recognized by recruiters and employers.
Credentials are blockchain-anchored via LearnCoin — tamper-evident, portable, link-shareable on LinkedIn and beyond.
Why Ewance
- DesignSeniorNew
Design a Cross-Chain Bridge Protocol with Honest Threat Model
Read the Vitalik 'cross-chain interoperability' essay and survey 3 existing bridge designs (lock-and-mint, atomic-swap, optimistic-rollup-native). Design your protocol around a …
- Blockchain Protocols
- Smart Contracts
- Solidity
Open coursework - CodeBeginnerNew
Diagnose and Fix a Deadlock in a Multi-Threaded Payments Service
Receive the service source (Java 21 + Spring Boot, around 30,000 lines), 4 thread dumps from production deadlocks, and a load harness that reproduces the bug roughly 1 in 50 run…
- Deadlock Analysis
- Locks And Monitors
- Java
Concurrent and Parallel Programming - DesignIntermediateNew
Stand Up a Self-Service Developer Platform on Backstage
Read the company case file, the squad-and-service inventory, and the Platform v1 postmortem, and consult the official Backstage software-templates documentation for the mechanic…
- Internal Developer Platform
- Backstage
- Terraform
Open coursework - AnalysisIntermediateNew
Reverse-Engineer a 22-Year-Old COBOL Batch Pipeline
Use SonarQube + cobol-language tooling + JCL parsers to extract job dependencies and data-flow across the 140 jobs. Build a job-dependency graph (Graphviz). Run impact analysis:…
- Reverse Engineering
- Legacy Systems
- Dependency Analysis
Software Evolution and Maintenance - 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 - CodeSeniorNew
Implement Threshold Signatures for a Multi-Sig Custody Service
Read the FROST IETF draft (draft-irtf-cfrg-frost) and the underlying Schnorr signature scheme on the secp256k1 curve. Implement the FROST distributed key generation (DKG) and 3-…
- Applied Cryptography
- Threshold Signatures
- Rust
Open coursework - DesignIntermediateNew
Cut a 42-Minute Trino Query to Under Five Minutes
Using the slow query, the EXPLAIN ANALYZE readout, the Iceberg table schemas, and the 30-day execution-metrics dataset provided, design an optimization proposal that cuts the cr…
- Trino
- SQL Optimization
- Iceberg
Open coursework - 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 - 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 - DesignBeginnerNew
Design a Wi-Fi 6E Coverage Plan for a Robot Warehouse
Using the warehouse layout and obstruction inventory, the robot fleet's radio requirements brief, and the existing Wi-Fi survey readout (all provided), design a Wi-Fi 6E access-…
- Wireless Networks
- Wifi 6e
- Site Survey
Open coursework - CodeBeginnerNew
Implement a User-Space Shell with Process and Signal Handling
Implement a shell in C (no shell helpers, just POSIX system calls). Required features: read a line, parse it into commands + arguments, handle pipelines with arbitrary chain len…
- System Calls
- Process Management
- Signal Handling
Computer Systems and Organization - DesignBeginnerNew
Design-System Component Library in Figma for a Travel Brand
Audit the existing app across the 7 squads to inventory every variant of each component (screenshot grid). For the 12 priority components, design canonical variants using Figma …
- Design Systems
- Figma
- Component Libraries
User Interface Design and Prototyping
How it works
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.
Related skill families
Browse all skillsIndustry teams behind a decade of practitioner briefs
Hiring from this pool?
Sponsor a challenge and meet candidates through actual work.
Industry teams can shape briefs around the skills they hire for, then evaluate students on rubric-scored deliverables — not resumes.