Go
If you like applying Go, every challenge here gives you a chance to practice it on a real industry brief.
- CodeAdvancedNew
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
Build a Reliable Transport Layer Over UDP
Implement in Go: connection establishment (3-way handshake), sequenced and acknowledged data segments, retransmission timer with exponential backoff, fast retransmit on triple d…
- Tcp Ip
- Reliable Transport
- Udp
Computer Networks - CodeAdvancedNew
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 - CodeAdvancedNew
Property-Based Testing for a SEPA Payments Library
Read the SEPA Pain.001 XSD (XML Schema Definition) and pick 5 invariants the parser MUST preserve (e.g., 'sum of transactions equals control sum', 'IBAN passes mod-97 check', 'c…
- Property Based Testing
- Fuzz Testing
- Go
Software Testing and Quality Assurance Practice your coursework on real scenarios.
Every challenge is shaped from real industry context — not generic exercises. The work mirrors what your degree prepares you for.
Why Ewance
- CodeAdvancedNew
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 - CodeAdvancedNew
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
- Api Design
API Design and GraphQL - CodeAdvancedNew
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 - CodeAdvancedNew
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 - 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.
- AnalysisAdvancedNew
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 - AnalysisIntermediateNew
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 - CodeExpertNew
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 - CodeIntermediateNew
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 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
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.
Industry 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.



















































































