Copilot Skills for AI-Assisted Migration

April 20, 2026 ยท View on GitHub

BlazorWebFormsComponents provides specialized Copilot Skills that enable AI-assisted migration from Web Forms to Blazor. These skills are frontmatter-based instruction files that give GitHub Copilot deep knowledge of BWFC migration patterns, shim infrastructure, and best practices.

What Are Copilot Skills?

Copilot Skills are markdown files with YAML frontmatter that contain:

  • Specialized knowledge about specific migration scenarios
  • Pattern recognition rules for transforming Web Forms patterns to Blazor
  • Decision frameworks for architecture choices
  • Anti-pattern detection to avoid common mistakes

When you reference a skill in a Copilot session, it gains context-specific expertise for that migration area.

Available Skills

BlazorWebFormsComponents provides three specialized migration skills:

1. Core Migration Skill

File: migration-toolkit/skills/bwfc-migration/SKILL.md

Purpose: Handles the core Web Forms Blazor markup and code-behind transformations (Layer 2 work).

What it covers:

  • Control tag transformations (asp:Button Button)
  • Expression conversions (<%: %> @())
  • Data binding patterns (SelectMethod, ItemType, templates)
  • Event handler signature updates
  • Master Page Layout conversions
  • Shim usage patterns (Session, Response, Request, Cache)

When to use: During Layer 2 migration when converting .razor files after the automated Layer 1 transforms have run.

Read the Core Migration documentation

2. Identity & Authentication Migration Skill

File: migration-toolkit/skills/bwfc-identity-migration/SKILL.md

Purpose: Guides migration of authentication and authorization from Web Forms to Blazor.

What it covers:

  • ASP.NET Identity (OWIN) ASP.NET Core Identity
  • ASP.NET Membership ASP.NET Core Identity
  • FormsAuthentication migration
  • Cookie authentication under Interactive Server mode
  • Login control migration (Login, LoginView, ChangePassword)
  • Role-based authorization patterns

When to use: When migrating login pages, account management, or any authentication-dependent features.

Read the Identity Migration documentation

3. Data & Architecture Migration Skill

File: migration-toolkit/skills/bwfc-data-migration/SKILL.md

Purpose: Handles Layer 3 architecture decisions and data access pattern migrations.

What it covers:

  • Entity Framework 6 EF Core migrations
  • DataSource controls service injection patterns
  • Session state to scoped services (when needed beyond SessionShim)
  • Global.asax Program.cs middleware
  • Web.config appsettings.json
  • HTTP handlers/modules middleware

When to use: During Layer 3 work when making architectural decisions about data access, state management, and application structure.

Read the Data Migration documentation

How to Use These Skills

Copy the skills/ directory from the migration-toolkit into your project:

# From your Blazor project root
mkdir -p .github/skills
cp -r path/to/bwfc-repo/migration-toolkit/skills/* .github/skills/

Then reference the skill in Copilot Chat:

@workspace Use the migration rules in .github/skills/bwfc-migration/SKILL.md 
to complete the migration of this file.

Option 2: Reference Skills from the BWFC Repository

If you have the BWFC repository cloned locally or as a submodule, reference skills directly:

Use the migration patterns from migration-toolkit/skills/bwfc-migration/SKILL.md 
to transform this page.

Option 3: Use the Copilot Instructions Template

For team-wide migration projects, use the copilot-instructions-template.md file to create project-specific Copilot instructions that reference all three skills:

cp migration-toolkit/copilot-instructions-template.md .github/copilot-instructions.md
# Edit the template to fill in project-specific details

Skill Selection Guide

Use this table to choose the right skill for your current migration task:

Migration TaskUse This Skill
Converting .aspx .razor markupCore Migration
Updating code-behind lifecycle methodsCore Migration
Master Page Layout conversionCore Migration
Data binding and templatesCore Migration
Login page migrationIdentity & Auth
ASP.NET Identity migrationIdentity & Auth
Cookie auth setupIdentity & Auth
EF6 EF Core migrationData & Architecture
SqlDataSource replacementData & Architecture
Session state architectureData & Architecture
Global.asax Program.csData & Architecture

Best Practices

1. Use Skills in Order

Follow the three-layer migration pipeline:

  1. Layer 1 Run automated transforms (CLI or PowerShell script)
  2. Layer 2 Use Core Migration skill for markup/code-behind
  3. Layer 3 Use Data & Architecture skill for architectural decisions
  4. Use Identity & Auth skill as needed when you encounter authentication

2. Reference Skills Explicitly

When asking Copilot for help, explicitly reference the skill file:

Using the patterns from .github/skills/bwfc-migration/SKILL.md, 
convert this Master Page to a Blazor Layout component.

3. Review AI Suggestions

Always review Copilot's suggestions before accepting them. The skills provide high-quality guidance, but context-specific nuances may require human judgment.

4. Combine Skills When Needed

Some pages may need multiple skills. For example, a login page needs both Core Migration (for markup) and Identity & Auth (for authentication logic).

Skill Maintenance

The skills are maintained in the BWFC repository and updated as:

  • New BWFC components are released
  • Shim infrastructure evolves
  • Migration patterns are refined based on community feedback

Check the BWFC repository for the latest versions.