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- DesignBeginnerNew
Architecture Decision Records for a Modernization Program
Read 18 weeks of architecture-channel Slack history and 6 architecture-review meeting notes to inventory decisions already made. Backfill 12 ADRs using Michael Nygard's template…
- Architecture Decision Records
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Technical Debt Management - CodeIntermediateNew
Instrument Network Telemetry for an ISP's Backbone
Receive the backbone topology (12 routers across 4 PoPs, mix of Cisco IOS XR + Juniper Junos), the current SNMP-based monitoring stack, and 4 weeks of customer-complaint tickets…
- Network Telemetry
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Advanced Computer Networks - 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…
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Cloud Computing - 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 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
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 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 - 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 - 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
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Container Orchestration with Kubernetes - 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.
- 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 - AnalysisIntermediateNew
Diagnose Modern Transport-Protocol Performance for an OTT Streamer
Receive the current delivery architecture (HTTP/2 origin + CDN), 4 weeks of Conviva-style QoE (quality of experience) metrics, and access to a synthetic-client harness (Linux + …
- Quic Http3
- Network Measurement
- Transport Protocols
Advanced Computer Networks - CodeSeniorNew
Profile and Tame a P99-Latency Tail for an Ad-Auction Service
Receive the bidder source (Go, around 22,000 lines), production traces (eBPF + flame graphs from 30 minutes of peak traffic), and the host config (NUMA-2 socket, 96 cores, 384GB…
- Performance Optimization
- Ebpf
- Go
Performance Engineering of Software Systems - DesignSeniorNew
Re-Architect a Data-Center Fabric for an AI-Training Workload
Receive the current 3-tier topology diagram, traffic captures from the existing fabric (4 weeks of sFlow), and the rack-level requirements for the 4 new H100 racks (200 Gbps per…
- Data Center Networking
- Bgp
- Evpn Vxlan
Advanced Computer Networks 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 an End-to-End Encrypted Messaging Protocol
Read the Signal protocol specifications (X3DH, Double Ratchet) and the team's current architecture (server-stored unencrypted messages). Design an E2EE protocol covering: identi…
- Applied Cryptography
- Protocol Design
- Rust
Applied Cryptography - 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 - 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 - CodeIntermediateNew
Reproducible Patient-Cohort Analysis for a Pharma AI Vendor
You receive a written cohort definition (type-2 diabetes patients on metformin for at least 90 days, aged 40-70) and a target output: 12-month HbA1c change distribution plus a K…
- Reproducible Analysis
- Cohort Analysis
- Survival Analysis
Applied Data Analysis and Practical Data Science - StrategyBeginnerNew
Strategy Brief on Layer-2 Choice for a Web3 Gaming Studio
Survey the three L2 categories with 2026-current numbers: per-transaction cost at expected game throughput (around 50 TPS sustained, 500 TPS event spikes), finality latency (mat…
- Layer 2 Protocols
- Blockchain Protocols
- Research
Blockchain and Decentralized Systems Engineering - 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
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), …
- API Design
- Idempotency
- Webhooks
API Design and GraphQL - CodeFoundationalNew
Edge Detection Pipeline for a Manufacturing QA Camera
Use a small provided dataset of around 200 part images under 3 lighting conditions. Build a classical pipeline using OpenCV: grayscale + adaptive thresholding + Canny edge detec…
- Image Processing
- Edge Detection
- Opencv
Computer Vision (Undergraduate) - 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 - 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
Blockchain and Decentralized Systems Engineering - DesignBeginnerNew
Build a Wi-Fi 6E Site Survey for an Industrial IoT Deployment
Receive the warehouse floor plan (CAD + obstruction inventory), the AMR fleet's RF requirements (6 GHz preferred, -67 dBm minimum, <50ms handover), and the existing Wi-Fi 5 site…
- Wireless Networks
- Wifi 6e
- Site Survey
Advanced Computer Networks - ResearchSeniorNew
Audit a Custom Cryptographic Protocol
Read the 22-page protocol spec, the Go reference implementation (around 4,000 lines), and the test vectors. Run a structured review covering: primitive choices (which cipher, MA…
- Applied Cryptography
- Cryptographic Audit
- Protocol Analysis
Applied Cryptography
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.
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