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Choose Your Adventure
Each adventure focuses on one open source technology, with challenges at different difficulty levels.New here? Start with The Accessibility Nightmare, a Accessibility adventure
7 adventures · 21 challenges
The Accessibility Nightmare
Audit the ShopSmart homepage and fix critical WCAG 2.2 accessibility violations before the initial compliance review.
Dead Reckoning
Fix a broken Backstage software template: debug the scaffolder steps that create a Gitea repository and register services in the catalog.
Lex Imperfecta
Fix broken Kyverno policies: repair CEL admission rules, scope a multi-namespace estate with PolicyException, and fix a Falco rule for runtime threat detection.
Blind by Design
Three levels of OpenFeature with flagd as the provider, in a Java + Spring Boot service. Wire the SDK against a flagd sidecar (Beginner), layer evaluation context to target by cohort (Intermediate), then instrument flag evaluations with OpenTelemetry and roll back a misbehaving fractional rollout (Expert). All without redeploying.
The AI Observatory
Investigate a mysterious bandwidth anomaly at a remote research station by instrumenting its AI system with OpenTelemetry, OpenLLMetry, and Jaeger.
Building CloudHaven
Join the Infrastructure Guild and modernize CloudHaven's infrastructure from manual provisioning to a self-service platform using Infrastructure as Code. A hands-on journey through infrastructure as code with OpenTofu and GitHub Actions.
- Beginner
The Initial Audit
- How to interpret automated axe-core accessibility reports.
- How semantic HTML affects keyboard and assistive-technology behavior.
- How to identify and correct WCAG color-contrast failures.
ChallengeThe Accessibility Nightmare - Intermediate
The Checkout Trap
- How to move, hold and restore focus across a modal boundary, and why hiding the background is not the same as putting it out of reach. (Dialog pattern)
- How to build a control that reports its own role, name, value and state, following the select-only combobox pattern.
- How a validation failure actually reaches a screen reader user, through live regions and the attributes that bind a message to its field.
ChallengeThe Accessibility Nightmare - Expert
The Compliance Engine
- Why a green accessibility gate means nothing until you know which pages and states it actually tested. (WCAG 2.4: Navigable)
- Why automated scanners cannot detect faults that only exist when a user does something, and which layer catches them instead. (Test and Evaluate Accessibility)
- How a single-page application can silently break the navigation contract that assistive technology depends on, and what it takes to restore it. (WCAG 4.1: Compatible)
ChallengeThe Accessibility Nightmare - Beginner
Laying the Keel
- How Backstage software templates are structured: parameters, steps, and output
- How scaffolder actions work, such as
fetch:template,publish:gitea, andcatalog:register - How the catalog registration step connects a scaffolded repository to the Backstage catalog
ChallengeDead Reckoning - Intermediate
Sea Trial
- How a Git webhook drives a workflow engine: Argo Events Sensors turn a push into a parameterized workflow run
- How Argo Workflows runs a multi-step delivery pipeline, and the RBAC its steps need
- How an Argo CD ApplicationSet auto-discovers repos and syncs them into the cluster
ChallengeDead Reckoning - Expert
The Chronometer
- How trace context crosses an asynchronous boundary with no call chain: a commission carries its W3C traceparent to a push-triggered pipeline, so its spans continue the same trace instead of starting a new one
- Why a distributed trace reveals what per-tool logs cannot: the value that flowed through each step, so a fault surfaces where the data diverges
- How to read that trace in Jaeger to localise a fault to a single service by following one attribute across the whole voyage
ChallengeDead Reckoning - Beginner
The Twelve Tables
- How Kyverno ValidatingPolicy resources and CELCommon Expression Language validation expressions work
- The difference between Audit, Deny, and Warn validation actions
- How to use custom label keys to enforce workload identity standards
ChallengeLex Imperfecta - Intermediate
Governing the Provinces
- How to scope policies using ValidatingPolicy (cluster-wide) and NamespacedValidatingPolicy (per-namespace), and when to use each
- How CEL expressions in
ValidatingPolicyandPolicyExceptionexpress fine-grained admission conditions - How to write and scope a PolicyException correctly so only the intended workloads are exempt
ChallengeLex Imperfecta - Expert
Quis Custodiet
- How Falco rules are structured: conditions, output, and kernel-level fields, and how to write a rule targeting a specific runtime behaviour
- Why
privileged: falseis not enough: how Linux capabilities grant host-level access without the privileged flag - How to use spec.variables in a
ValidatingPolicyto share reusable CEL expressions across validations
ChallengeLex Imperfecta - Beginner
Stand up the Lab
- How an OpenFeature client and provider work together: the SDKSoftware Development Kit is provider-agnostic and the flagd provider plugs in via dependency only
- What remote provider means in practice: the SDK calls a separate flag service (flagd) over gRPCGoogle Remote Procedure Call, not parsing flags.json itself
- What flags.json looks like for flagd (state, variants, defaultVariant)
ChallengeBlind by Design - Intermediate
Outcome by Cohort
- How OpenFeature's transaction-context propagation works in a thread-per-request server, and why a ThreadLocalTransactionContextPropagator is the right primitive for Servlet-based apps
- The difference between request-scoped context (the subject's species) and global evaluation context (the trial's country), and when each is the right tool
- How hooks let you attach cross-cutting behaviour, audit logging today and OpenTelemetry tracing tomorrow, without modifying every flag evaluation call site
ChallengeBlind by Design - Expert
Read the Chart
- How the OpenFeature OpenTelemetry hooks (TracesHook and MetricsHook) join flag evaluations to the rest of an application's telemetry without a separate ingestion path
- How to author your own Hook: a tiny class that copies merged-eval-context attributes onto the active OTelOpenTelemetry span, closing the loop between why a flag resolved the way it did and what the operator sees in Tempo
- How fractional rollout in flagd buckets users by targetingKey (same key, same bucket, every request) and how to read that bucketing off a dashboard
ChallengeBlind by Design - Beginner
Calibrating the Lens
- Instrument Python AI apps with OpenLLMetry
- Analyze traces in Jaeger
ChallengeThe AI Observatory - Intermediate
The Distracted Pilot
- Instrument RAGRetrieval-Augmented Generation pipelines with OpenLLMetry
- Create custom OpenTelemetry metrics in Python
- Write PromQL queries & recording rules in Prometheus
ChallengeThe AI Observatory - Expert
The Noise Filter
- OpenTelemetry GenAI semantic conventions
- Tail sampling in the OTelOpenTelemetry Collector
ChallengeThe AI Observatory - Beginner
The Foundation Stones
- Infrastructure as Code with OpenTofu
- Remote state management with GCSGoogle Cloud Storage backend
- Dynamic resource provisioning with for_each
ChallengeBuilding CloudHaven - Intermediate
The Modular Metropolis
- OpenTofu module testing with tofu test
- Test-Driven Development (TDD) workflow
- Input validation with custom rules
ChallengeBuilding CloudHaven - Expert
The Guardian Protocols
- GitHub Actions for drift detection and plan/apply
- Integration tests with service containers
- Security scanning with Trivy
ChallengeBuilding CloudHaven - Beginner
Broken Echoes
- Debug GitOpsGit Operations flows with Argo CD
- ApplicationSet templating & pitfalls
- Environment isolation & namespaces
ChallengeEchoes Lost in Orbit - Intermediate
The Silent Canary
- Progressive delivery with Argo Rollouts
- Canary deployments & automated analysis
- Write PromQL queries for health validation
ChallengeEchoes Lost in Orbit - Expert
Hyperspace Operations & Transport
- Configure OpenTelemetry Collector pipelines
- Spanmetrics connector (traces to metrics)
- Detect idle canaries with traffic validation
ChallengeEchoes Lost in Orbit
No challenges match these filters.
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