Computer Science
Programming Fundamentals Challenges
Programming Fundamentals challenges put you inside the work of writing code that is correct, readable and fast. You'll build core skills in functions & data structures, object-oriented design and design patterns, work in Python or JavaScript, and learn to do code reading and refactoring the way teams expect.
From there you'll tackle the harder edges — algorithm analysis, complexity analysis, graph algorithms and generics & type systems — pushing into performance engineering, low-latency programming patterns and systems-language proficiency (Go, Rust, C++). Each challenge you solve earns a verified credential you can share with recruiters.
Recommended Challenges
· Systems-language proficiency (Go, Rust, C++) Clear- 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
Applied Cryptography - CodeSeniorNew
Port a Numerical Kernel from CPU to GPU for a CFD Simulator
Receive the existing CFD solver (C++17 + OpenMP, around 8,000 lines, the hot kernel is a 7-point stencil sweep over a 512^3 grid), the validation harness, and access to an A100 …
- Gpu Programming
- Cuda
- Parallelism
Performance Engineering of Software Systems - CodeIntermediateNew
Prove a gRPC Migration for a Kubernetes Control-Plane API
Examine three things: the captured control-plane traffic record (`traffic-7d`), the current REST API specification (`openapi-spec`), and the representative Go service module (`g…
- Grpc
- Protobuf
- API Design
Open coursework - CodeBeginnerNew
Design and Implement a C++ Telemetry Aggregator With Inheritance
Implement a TelemetrySource abstract base class with virtual sample() and timestamp() methods, 6 concrete subclasses (one per sensor family), and a TelemetryBus that polymorphic…
- Cpp
- Inheritance
- Polymorphism
Object-Oriented Programming and Design 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
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 - 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 - DesignIntermediateNew
Add Profile-Guided Optimization to a Production JavaScript Bundler
Design and implement a profile-guided optimization workflow for the bundler using Rust's LLVM-based PGO: an instrumented build, a training run over the eight-project benchmark c…
- Profile Guided Optimization
- Llvm
- Benchmarking
Open coursework - AnalysisBeginnerNew
Profile and Optimize a Virtual-Memory-Heavy Image Pipeline
Receive the Go pipeline source, a representative batch (1,200 photos averaging 12MB each, with 30 outliers over 80MB), and host specs (4-core, 16GB RAM, Linux kernel 5.15). Run …
- Virtual Memory
- Performance Profiling
- Memory Hierarchy
Computer Systems and Organization - 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.
- CodeBeginnerNew
Build a CPU-Only Teaching Rasterizer in C++
Using the provided test-scene model file and the reference render image, implement a software rasterizer in C++ that runs only on the central processor. Build the supporting mat…
- Rasterization
- Geometric Transformations
- 3d Rendering
Open coursework - 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 - 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 - 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 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
Implement and Tune HyperLogLog for Trace-Stream Cardinality in Go
Working from the HyperLogLog paper (provided as a real source) and the provided representative trace sample, implement HyperLogLog from scratch in Go with no third-party algorit…
- Randomized Algorithms
- Sketching
- Algorithm Analysis
Open coursework - 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 - CodeIntermediateNew
Design Error Recovery for a Friendly Compiler
Read the existing parser (recursive-descent, in Rust). Design and implement a panic-mode error recovery strategy with synchronization tokens (statement boundary, end of block, s…
- Error Recovery
- Recursive Descent Parsing
- Diagnostic Design
Compiler Construction - 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 - DesignSeniorNew
Design an End-to-End Encrypted Messaging Protocol for Clinicians
Using the Vireo current-architecture case file and the Signal protocol specifications listed in provided materials, design an end-to-end encrypted messaging protocol that covers…
- Applied Cryptography
- Protocol Design
- Rust
Open coursework - CodeIntermediateNew
Property-Based Testing to Harden a SEPA Payments Parser
Work only from the four supplied items: the de-identified incident log of the last four quarterly parser failures (incident-log), the representative parser module (parser-module…
- Property Based Testing
- Fuzz Testing
- Go
Open coursework - AnalysisIntermediateNew
Penetration-Test the TLS Configuration of an Edge Fleet
Receive read-only access to a 50-node representative sample (anonymized). Scan with testssl.sh + Qualys SSL Labs (where reachable) + a custom Go tool you write to test specific …
- Tls
- Applied Cryptography
- Penetration Testing
Applied Cryptography - 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
Implement a Proof-of-Stake Consensus Mechanism in Rust
Read the Casper FFG paper (Buterin + Griffith, 2017) and design a simplified PoS implementation in Rust: 21 validators, 32-slot epochs, two-phase finality (justify, then finaliz…
- Consensus Algorithms
- Blockchain Protocols
- Rust
Blockchain and Decentralized Systems Engineering - 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 - 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 - 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
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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