Engineering task library · Version 5 Work that feels like work. Design a system. Diagnose tail latency. Ship a migration. Recover a failed rollout. Pick a focused ticket or follow a project through its delivery phases.
1380 tickets · 138 projects · 26 engineering fields · Four difficulty levels
Practice briefs Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Completing a ticket does not issue a credential.
AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior.
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Pattern topics identify design choices to practice. Read the ticket's acceptance criteria and justify the simplest suitable approach. Tags are not capability or ownership evidence; an untagged ticket has no curated pattern topic assigned.
Field counts and the engineering field filter use each project's primary field. Estimated ticket labels can span multiple fields.
Backend 60 Data engineering 50 Platform engineering 50 Security 50 Frontend 60 Mobile 50 Developer tooling 50 Quality engineering 50 Applied AI 50 Integrations 60 Real-time systems 50 Accessibility 50 System design 60 Performance engineering 50 Database engineering 50 Distributed systems 60 Site reliability 50 Cloud infrastructure 50 Networking 50 API design 50 Storage systems 50 Compiler and language tooling 60 Embedded and edge 50 Privacy engineering 50 Systems programming 60 DevOps 60 CDOWN-107 Bug Expert
A crash between verification and final rename leaves duplicate shelf entries. Introduce a recoverable promotion record.
Estimated field mix
Storage systems 50% Mobile 30% Database engineering 20% A dependable mobile course-download shelfCDOWN-108 Task Advanced
Deleting a course removes an image another course references. Track local references before reclaiming shared blobs.
Estimated field mix
Storage systems 70% Mobile 30% A dependable mobile course-download shelfCDOWN-109 Bug Intermediate
Small network chunks trigger excessive mobile renders. Coalesce progress updates while keeping completion immediate.
Estimated field mix
Performance engineering 60% Mobile 40% A dependable mobile course-download shelfCDOWN-110 Story Intermediate
Users cannot recover one corrupt course without clearing the entire app. Add repair for the selected course only.
Estimated field mix
Mobile 50% Storage systems 50% A dependable mobile course-download shelfCLINK-101 Task Foundational
Pasted links with missing invitation IDs crash route construction. Add strict parsing before mounting screens.
Mobile invitation and session navigationCLINK-102 Story Foundational
Expired invitations spin indefinitely because the client treats every response as transient. Render terminal expiry distinctly.
Mobile invitation and session navigationCLINK-103 Story Intermediate
Signing in from an invitation lands on the dashboard. Preserve a validated destination until identity is available.
Mobile invitation and session navigationCLINK-104 Bug Advanced
Switching accounts leaves the previous account's work screen visible. Clear account-scoped cache before refetching.
Mobile invitation and session navigationCLINK-105 Task Advanced
Opening a linked screen triggers three refresh calls and conflicting session updates. Share one in-flight refresh.
Estimated field mix
Mobile 50% Security 30% Performance engineering 20% Mobile invitation and session navigationCLINK-106 Bug Intermediate
An invitation opened before account switching completes under the wrong identity. Bind continuation to the initiating session generation.
Mobile invitation and session navigationCLINK-107 Story Expert
An emulator restart during local sign-in loses the requested destination. Persist minimal, expiring continuation state.
Mobile invitation and session navigationCLINK-108 Bug Intermediate
After joining a team, Back returns to a completed sign-in screen that resubmits. Replace transient routes on success.
Mobile invitation and session navigationPPOLICY / Backend Evolve a quoting module as partner contracts diverge, while keeping calculations reproducible and abstractions proportional to the problem.
PDOC / Frontend Build a bounded browser editor whose tree operations, history, subscriptions, and exports remain coherent under failures and repeated use.
PPROVIDER / Integrations Support two incompatible notification providers while keeping domain decisions, instrumentation, and overload behavior explicit.
PDSL / Compiler and language tooling Replace a growing set of warehouse eligibility switches with a small, bounded rule language that support can inspect and engineers can evolve.
PMIGRATE / System design Evolve a long-lived account module while preserving tenant boundaries, client contracts, and a credible route back from partial migration.
PRECOVER / Distributed systems Coordinate return inspection, replacement stock, and refunds across controllable provider boundaries while keeping uncertain outcomes visible.
SMEM / Systems programming Build a bounded arena with explicit alignment, lifetime and corruption behavior.
SCONCUR / Systems programming Implement bounded scheduling, cancellation and shutdown without hidden liveness failures.
SIPC / Systems programming Build framed IPC, bounded buffering, process lifecycle control and restart-safe request identity.
SRUNTIME / Systems programming Implement decoding, stack safety, resource budgets and compatible bytecode revisions.
SFFI / Systems programming Design a safe FFI contract with explicit ownership, error mapping and compatibility.
SKERNEL / Systems programming Wrap files, timers and readiness notifications with explicit partial-result and portability behavior.
Take the brief into your own workflow. For engineers Practice scoped changes, keep a portable implementation and verification record, and learn to explain operational tradeoffs. Choose a ticket whose prerequisites you can provide.
For companies Use realistic work to structure onboarding, internal practice, and conversations about engineering decisions. Each project names the delivery benefit. Agree scope and compensation before requesting company-specific work.
CSV contains one row per ticket. Map fields and issue types in your tracker; project grouping and dependency keys are descriptive. JSON preserves the complete project structure. These downloads do not synchronize with Jira.