Practical, sourced guidance for the technical leaders who own systems too critical to touch and too old to keep — organized as series.
What legacy modernization is, why most programs fail, and how to do it slice by slice.
12 parts· 2h 30m Start reading → VOL 02 IntermediateHow to replace a legacy system slice by slice — routing, anti-corruption layers, and per-slice validation — without a big-bang rewrite.
8 parts· 1h 11m Start reading → VOL 03 IntermediateHow a modernized slice is proven to behave identically to the legacy system it replaces — before it carries live traffic.
8 parts· 1h 5m Start reading → VOL 04 IntermediateWhy big-bang rewrites fail, how incremental replacement controls the risk, and how leadership should choose — the decision and governance behind replacing a system slice by slice.
8 parts· 1h 6m Start reading → VOL 05 IntermediateWhere AI genuinely changes legacy modernization and where it does not — discovery, translation, and validation under human-in-the-loop review, never autonomous.
10 parts· 1h 35m Start reading → VOL 06 IntermediateHow the undocumented rules a system depends on get lost — and how to capture them from the code as living specs, before the people who hold them leave.
8 parts· 1h 21m Start reading → VOL 07 FoundationalWhat application modernization is, the patterns and the business case, and how to assess a portfolio and measure the return.
10 parts· 1h 56m Start reading → VOL 08 For leadershipWhat modernization costs, how to calculate ROI and the cost of inaction, and how to build the business case that gets it funded.
9 parts· 1h 30m Start reading → VOL 09 IntermediateWhat technical debt really costs, how to measure and price it, and how to pay it down without halting delivery.
13 parts· 2h 26m Start reading → VOL 10 IntermediateWhy end-of-life software, unpatched runtimes, and audit findings become urgent risk — and how to modernize for security and compliance without a full rewrite.
10 parts· 1h 34m Start reading → VOL 11 FoundationalThe 2025 Microsoft EOL cliff — Windows, Server, SQL, Office, Exchange: what end of support really costs, why ESU and "just upgrade" both fail, and the incremental path off each platform before the deadline.
10 parts· 1h 26m Start reading → VOL 12 IntermediateWhat cloud migration really involves — the 7 Rs, lift-and-shift vs refactor, why migrations fail, and what it costs.
10 parts· 1h 59m Start reading → VOL 13 IntermediateWhen to break up a monolith and when not to — service boundaries, decomposing the database, and the distributed-monolith trap.
10 parts· 1h 56m Start reading → VOL 14 AdvancedModernizing z/OS, COBOL, CICS, DB2, JCL and VSAM — the approaches, the challenges, and how to de-risk the core of the enterprise.
12 parts· 2h 25m Start reading → VOL 15 AdvancedThe language at the heart of the mainframe — dialects and data structures, the talent cliff, and how to convert, rewrite, or replace COBOL onto Java, C#, or Python without losing the rules.
10 parts· 2h 22m Start reading → VOL 16 AdvancedModernizing the AS/400 — RPG, DB2 for i, and the 5250 green screen — without losing the enforced business rules. A skills-and-agility decision, since IBM i is actively supported.
9 parts· 1h 53m Start reading → VOL 17 AdvancedModernizing the core — COBOL, mainframe, payments — without an outage or a failed audit, slice by slice under FFIEC/OCC, GLBA, and NYDFS Part 500.
9 parts· 1h 53m Start reading → VOL 18 AdvancedModernizing the insurance core — policy admin, rating, underwriting, and claims — by recovering the undocumented rules as living specs and migrating slice by slice, parity-proven.
9 parts· 1h 50m Start reading → VOL 19 AdvancedModernizing payer and provider systems — claims, eligibility, and EHR-adjacent platforms wired together by brittle HL7/EDI/FHIR interfaces — slice by slice, without breaking the interface mesh or the audit posture.
8 parts· 1h 23m Start reading → VOL 20 AdvancedMoving .NET Framework apps onto modern .NET — Web Forms, WCF and ASMX, VB6/VB.NET, and monoliths — slice by slice, parity-proven, with the platform move kept separate from the architecture decision.
8 parts· 1h 25m Start reading → VOL 21 IntermediateModernizing a legacy Java estate slice by slice — old JDK to a modern LTS JVM, Java EE to Jakarta EE / Spring Boot, and EJB and app-server monoliths to domain services, parity proven.
9 parts· 1h 44m Start reading → VOL 22 AdvancedModernizing an Oracle Forms, Reports & PL/SQL estate — surfacing the business logic buried in the database as explicit domain services, rebuilding the UI as a modern SPA or APEX, and deciding whether to upgrade or re-platform the database.
8 parts· 1h 29m Start reading → VOL 23 IntermediateHow a maturing SaaS company modernizes a live product slice by slice — paying down debt that slows the roadmap, scales badly, and discounts the valuation, without ever freezing the roadmap.
9 parts· 1h 32m Start reading → VOL 24 IntermediateHow an ISV modernizes an installed or licensed product — one aging codebase shipped across many customer environments — slice by slice: service tier, web front end, multi-tenancy, and subscription delivery, without a big-bang release.
8 parts· 1h 27m Start reading → VOL 25 For leadershipThe honest "it depends" guides — modernize vs replace, build vs buy, in-house vs partner, GSI vs boutique, and how to evaluate a modernization vendor.
7 parts· 58m Start reading → VOL 26 ReferencePlain, citable definitions of the core modernization terms — legacy systems, refactoring, microservices, the strangler pattern, and more.
14 parts· 1h 21m Start reading → VOL 27 IntermediateWhat vendor lock-in really costs across vendor, platform, skills, and data — the compounding maintenance bill it produces, and how to escape it slice by slice.
8 parts· 1h 34m Start reading → VOL 28 For leadershipHow to decide whether to build, buy, or modernize a system that matters — the true TCO of each path, a copyable scored decision matrix, the reversibility nobody prices, and the third option that often wins.
5 parts· 1h 7m Start reading →