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proskillv1.0.0

legacy-modernization

Modernize legacy systems without a rewrite bet — strangler-fig migration, finding seams, characterization tests before touching anything, anti-corruption layers, incremental database decomposition, and the rewrite-vs-refactor decision made with evidence.

$npx vanara install legacy-modernization

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Overview

"Legacy" means: it makes money and everyone is afraid of it. The failure mode isn't the old code — it's the modernization itself: the two-year rewrite that ships nothing while the old system keeps evolving, then dies in the cutover. The antidote is incremental replacement with the old system as the safety net. Deep detail in references/; a strangler routing plan and characterization-test harness i

What it covers

Details

Tier
Pro — $10/mo
Version
1.0.0
Depth
2 references · 2 examples · 0 runnable scripts
Runs on
Your own Claude Code — no API keys
api-paginationImplement correct, fast API pagination — cursor vs offset trade-offs, opaque cursor encoding, stable sort keys, page-size limits, total-count costs, and consumer-side iteration that survives inserts, deletes, and retries. With runnable cursor checks.app-store-optimizationHow to optimize an app-store listing (ASO) for discovery and conversion — title, subtitle, keywords, screenshots, icon, ratings, and the metadata that drives installs. A deep reference with worked Apple and Google listings and a runnable listing linter.audit-loggingDesign tamper-evident audit logs that satisfy security and compliance — what to record (who/what/when/where/outcome), what to never log (secrets/PII), structured immutable events, hash-chaining for tamper-evidence, retention, and access control. A deep reference with runnable validation.background-jobsDesign background job systems that don't lose or double work — enqueue-after-commit, retry policies with jitter, idempotent handlers, visibility timeouts, priority lanes, scheduled and recurring jobs, worker scaling, and observability for async work. With a runnable retry-policy check.backup-and-recoveryDesign and operate a tested backup and disaster-recovery strategy — the 3-2-1 rule, RPO/RTO targets, full vs incremental vs differential, point-in-time recovery, encryption, offsite/immutable copies, retention, and the restore drills that prove a backup actually works.c4-diagrammingDocument software architecture with the C4 model (Context, Container, Component, Code) as text-based diagrams in version control. Covers the four abstraction levels, notation discipline, when to draw each level (and when to stop), supplementary diagrams, and Mermaid/Structurizr tooling.
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