What does the Osmond skill do?

Modernize safely: count the real rules, pick the right R per module, and route traffic across without breaking the business. Load it once into Claude Projects and you get a configured Legacy Modernization & Mainframe Engineer without re-explaining context at the start of every session. Measure the system before changing it, prove the change on a real workload in a staging environment, and ship it behind a rollback you have actually tested rather than one you assume works.

How do I install this skill file?

Download the .skill package (it contains SKILL.md), paste the contents into Claude Projects Instructions or your AI's system prompt, add your own context and start your first session. Works with Claude, ChatGPT, or any AI chat that accepts system prompts.

Which AI tools does this skill work with?

Works with Claude (recommended), ChatGPT, Gemini, Perplexity and Copilot, and any AI chat that accepts system prompts. Claude Projects gives the best results.

What is included in this download?

One .skill package delivered instantly after purchase: the full SKILL.md role configuration plus a worked-example file with a real scenario so you see the quality before you rely on it. No subscription, yours permanently.

How is this different from using Claude without the Osmond skill?

Without a skill file your AI starts every session as a general assistant. With Osmond loaded it applies Legacy Modernization & Mainframe Engineer methodology from the first message, with consistent quality every time. Measure the system before changing it, prove the change on a real workload in a staging environment, and ship it behind a rollback you have actually tested rather than one you assume works.

Legacy Modernization & Mainframe Engineer AI Skill for Claude & ChatGPT

Name: Osmond — Legacy Modernization & Mainframe Engineer AI Skill
Brand: KissMySkills
Price: 14.99 USD
Availability: InStock

Osmond — Legacy Modernization & Mainframe Engineer AI Skill

$14.99

Osmond — Legacy Modernization & Mainframe Engineer AI Skill

$14.99 this skill vs $165+/hr, hiring one

⚡ Instant download ◆ Claude & ChatGPT ∞ Keep forever

Instant download · 30-day money-back guarantee. Pay once, keep forever — no subscription. Refund policy

Modernize safely: count the real rules, pick the right R per module, and route traffic across without breaking the business.

COBOL, JCL, CICS, VSAM and DB2 read and changed safely
The six-R decision argued from a real rule and dependency count
Strangler fig routing, anti-corruption layers and API facades
EBCDIC and packed-decimal traps, batch windows and MSU cost

Organizations whose core system is decades old and whose rewrite estimate came from optimism rather than evidence.A mainframe modernization consultant commands $165+/hr, this is one file, yours forever.

// what's inside

Drop Osmond into Claude and get a mainframe and modernization engineer who counts the business rules before anyone commits to an eighteen-month rewrite.

Osmond works on the systems that still run the business: COBOL, JCL, CICS, IMS, VSAM and DB2 on z/OS; reading and safely changing code nobody documented; the modernization decision across rehost, replatform, refactor, rewrite, replace and retain, argued from evidence rather than fashion; the strangler fig pattern and incremental traffic routing; batch window analysis and job dependency mapping; data migration off hierarchical and flat-file stores; EBCDIC and packed-decimal conversion traps; anti-corruption layers and API facades over a core system; mainframe cost drivers including MIPS, MSU and the four-hour rolling average; regression risk when there are no tests; knowledge capture from retiring staff; and the cases where a rewrite is simply the wrong answer.

What you get

→COBOL, JCL, CICS, VSAM and DB2 read and changed safely
→The six-R decision argued from a real rule and dependency count
→Strangler fig routing, anti-corruption layers and API facades
→EBCDIC and packed-decimal traps, batch windows and MSU cost

📄 osmond-legacy-modernization-mainframe.skill Under 2 min install Works with Claude, ChatGPT & any AI chat

How to install

Download the .skill package → open Claude → paste SKILL.md into your Project Instructions or system prompt → describe your requirement → Osmond builds the answer. Includes a full worked example so you see exactly what you get.

osmond-legacy-modernization-mainframe.skill

# Osmond - Legacy Modernization & Mainframe Engineer

You are Osmond, a legacy modernization and mainframe engineer. Count the business rules before believing any rewrite estimate.

## How you work
1. Inventory programs, rules and batch dependencies before deciding anything
2. Choose an R per module, not one answer for the whole system
3. Route traffic incrementally behind an anti-corruption layer
4. Prove equivalence with a parallel run and a numeric go or no-go bar

Never change a program you cannot regression test, and tell the client plainly when the approved timeline is arithmetically impossible.

Excerpt from the actual file you'll download.

// try it

prompt

$The board approved an 18-month rewrite of our core policy system. Make it happen.

Osmond returns a real inventory of programs and business rules with the honest duration range that implies, a six-R decision per module rather than one answer for everything, a strangler fig routing plan, a batch dependency and critical path map, the data conversion traps with worked examples, a parallel-run reconciliation design with a go or no-go threshold, and the MSU cost consequence of the migration sequence.

// how to install Under 2 minutes

Four steps. Any AI chat.

01
Download the file
After checkout, the download link lands in your inbox. Save the file anywhere on your device.
02
Open your AI chat
Claude, ChatGPT, Gemini, Grok, or Copilot — whichever one you already use.
03
Paste the file contents
Drop it into the system prompt, Project instructions, or custom instructions field.
04
Start working
Your AI is now configured as a specialist. Ask it anything inside its domain.