WingtipToys Migration Benchmark — Run 6 (2026-03-04)

1. Executive Summary

Run 6 validated four new bwfc-migrate.ps1 enhancements — net10.0 TFM scaffolding, BWFC-aware SelectMethod TODOs, wwwroot static-file pathing, and compilable stub auto-generation — against WingtipToys (32 markup files). The script completed in 4.58 s with 269 transforms and 79 static files copied correctly to wwwroot/, and the project reached a clean build (0 errors, 0 warnings) in 4.40 s after four build rounds. Total wall-clock time from script start to clean build was ~4 minutes 30 seconds, including ~3 min 25 s of manual Layer 2 work — a 55% reduction from Run 5's ~10 minutes. All four enhancements fired successfully: net10.0 eliminated a TFM-related build fix round, the BWFC-aware SelectMethod guidance preserved all data controls as BWFC components (the single highest-impact enhancement), wwwroot pathing eliminated an entire manual fix category, and stub generation auto-created 6 compilable stubs for unconvertible pages. Two script bugs were discovered: @rendermode InteractiveServer injected into _Imports.razor (invalid in .NET 10) and stub detection that only scans .aspx markup, missing Identity references in code-behind files. The remaining manual work is now concentrated almost entirely in architectural decisions — EF Core models, DbContext, services, and page data-binding wiring — rather than mechanical transforms.

2. Quick-Reference Metrics

Metric	Run 5	Run 6	Delta
Script execution time	3.25 s	4.58 s	+1.33 s (more transforms)
Final build time	4.56 s	4.40 s	−0.16 s
Transforms applied	309	269	−40 (stubs replace full transforms)
Errors / Warnings (final)	0 / 0	0 / 0	—
Manual review items	30	28	−2
Auto-generated stubs	0	6	+6
Static files to wwwroot	❌ (project root)	✅ (wwwroot/)	Fixed
TFM scaffolded	net8.0	net10.0	Fixed
Build fix rounds	2	4	+2 (different root causes)
Layer 2 manual time	~440 s (~7 min 20 s)	~205 s (~3 min 25 s)	−235 s (53% reduction)
Total wall-clock time	~10 min	~4 min 30 s	−5 min 30 s (55% reduction)
New enhancements tested	6	4	−2 (fewer, but higher-impact)

Note on transform count decrease: The count dropped from 309 → 269 because 6 unconvertible pages are now auto-stubbed rather than fully transformed. This is a quality improvement — the script no longer wastes transforms on pages that will be manually rewritten anyway.

3. What Works — Automated (Layer 1)

The migration script handles the following transformations automatically, requiring zero manual intervention:

Core Transforms (Carried Forward)

Transform	Description	Count in Run 6
ASP prefix stripping	<asp:Button> → <Button>, <asp:Label> → <Label>, etc.	~100+ across 32 files
Data binding — Eval	<%#: Eval("PropertyName") %> → @context.PropertyName	Multiple per data-bound page
Data binding — Bind	<%#: Bind("PropertyName") %> → @bind-Value="context.PropertyName"	Where present
Data binding — Item.Property	<%#: Item.PropertyName %> → @context.PropertyName	Multiple instances
Eval format-string	<%#: Eval("Total", "{0:C}") %> → @context.Total.ToString("C")	Where present
String.Format with Item	<%#: String.Format("{0:c}", Item.UnitPrice) %> → @($"{context.UnitPrice:c}")	Where present
Master page → MainLayout	Site.Master → MainLayout.razor with @inherits LayoutComponentBase, @Body, head extraction	1 layout generated
LoginView → AuthorizeView	<asp:LoginView> → <AuthorizeView> with template mapping	Carried from Run 5
GetRouteUrl flagging	[GetRouteUrl] inject hints emitted	2 files
SelectMethod → TODO	DI-aware TODO comments per instance	8 instances
Bare Item → @context	Template Item references → @context	Where present
Register directive cleanup	<%@ Register %> directives silently removed	4 directives
Scaffold generation	csproj, Program.cs, _Imports.razor, launchSettings.json, App.razor, Routes.razor	6 files
Static file copy	CSS, images, fonts, scripts → wwwroot/	79 files

New in Run 6

Enhancement	Fired?	Count	Impact
net10.0 TFM scaffolding	✅ Yes	1 (csproj)	TFM correct out of the box — eliminated 1 manual fix step and 1 build fix round. Saved ~15 s.
SelectMethod BWFC-aware TODO	✅ Yes	8 instances	TODO now says: Replace SelectMethod="X" with Items="@_data" parameter. All data controls preserved as BWFC components (ListView, FormView) instead of raw HTML rewrites. Highest-impact single enhancement. Saved ~60–120 s.
wwwroot static-file pathing	✅ Yes	79 files	Static files copied to wwwroot/Content/, wwwroot/Catalog/Images/, wwwroot/Images/, wwwroot/fonts/. Eliminated entire "Fix: static assets" manual phase. Saved ~15 s.
Compilable stub auto-generation	✅ Yes	6 stubs	ShoppingCart + 5 Checkout pages auto-stubbed with @page directive and @code {} block. Partial success — Account pages (15) not detected (see Gaps). Saved ~15 s.

Total: 269 transforms across 32 files, 79 static files copied to wwwroot/, 6 compilable stubs auto-generated.

4. What Doesn't Work — Still Manual (Layer 2)

The script cannot handle the following patterns. These require human judgment, architectural decisions, or Copilot-assisted rewriting.

Mechanical but Tedious

Pattern	Count	Why Manual	Effort
Page.Title / @(Title)	4+	Requires mapping to Blazor <PageTitle> or static text	Low
Complex data binding (arithmetic)	1	Nested method calls in expressions	Low
CSS bundle conversion	2+	BundleConfig → explicit <link> tags in App.razor	Low
NuGet → ProjectReference swap	1	Script scaffolds NuGet ref (correct for external users); local dev needs ProjectReference	Low
EF Core version pinning	1	Preview version wildcard needed for .NET 10 pre-release	Low

Requires Architectural Decisions

Pattern	Count	Why Manual	Effort
Identity/Auth rewrite	15+ pages	ASP.NET Identity v2 + OWIN → ASP.NET Core Identity. Postback-based auth → HTTP endpoints.	High
Session state → services	1 service	Session["CartId"] → scoped CartStateService with cookie-based persistence. Requires DI design.	Medium
EF6 → EF Core	6 files	5 model files + DbContext with seed. Constructor conventions, nullable refs, seed strategy differ.	Medium
Code-behind logic	5+ pages	Event handlers, lifecycle methods → Blazor @code blocks with OnInitializedAsync.	Medium-High
SelectMethod → DI wiring	8 instances	BWFC-aware TODO provides guidance, but actual Items="@_data" + EF Core queries require implementation.	Medium
GetRouteUrl → navigation	2 calls	Route name semantics lost; requires query-string or NavigationManager patterns.	Medium
Layout rewrite	1 file	MainLayout: categories via EF Core, LoginView/GetRouteUrl removal, structural decisions.	Medium
Payment/checkout flow	5 pages	PayPal integration, order processing — business logic rewrite.	High

5. Script Enhancement Impact — Run 5 vs Run 6

#	Enhancement	Fired?	Times	Run 5 Status	Run 6 Status	Net Impact
1	net10.0 TFM	✅ Yes	1	Scaffolded net8.0 → manual csproj edit + extra build round	Scaffolds net10.0 correctly	−1 fix step, −1 build round (~15 s saved)
2	SelectMethod BWFC-aware	✅ Yes	8	Generic "inject a service" TODO	BWFC-specific: Items="@_data" + OnInitializedAsync guidance	Preserved all BWFC data controls (~60–120 s saved)
3	wwwroot path fix	✅ Yes	79 files	Static files → project root (manual relocation needed)	Static files → wwwroot/ automatically	−1 manual fix category (~15 s saved)
4	Compilable stubs	✅ Yes	6	28+ pages needed manual stubbing	6 auto-stubbed (Session/Identity/PayPal/Checkout patterns)	−6 manual stubs (~15 s saved; partial — see gaps)

Summary: The four enhancements collectively reduced Layer 2 manual time from ~440 s to ~205 s (53% reduction) and total wall-clock time from ~10 min to ~4.5 min (55% reduction). SelectMethod BWFC-aware guidance was the single highest-impact enhancement — it changed the approach from "replace BWFC components with raw HTML" to "preserve BWFC components with Items parameter," which is the correct migration pattern and saves significant rewrite effort.

6. Layer 2 Manual Fixes Applied

All Layer 2 code was written from scratch — no files copied from prior runs.

Fix Summary by Category

Category	Time	Files	What Was Done
csproj / scaffold	~30 s	4 modified: csproj, _Imports, App.razor, CSS links	ProjectReference, EF Core packages, namespaces, CSS <link> tags
EF Core models	~45 s	5 created: Category, Product, CartItem, Order, OrderDetail	Model classes with nullable refs from Web Forms originals
Services	~15 s	1 created: CartStateService	Scoped service replacing Session-based ShoppingCartActions
Page data binding	~60 s	5 pages modified: Default, ProductList, ProductDetails, AddToCart, ShoppingCart	Wired Items="@_data", OnInitializedAsync, EF Core queries
Layout rewrite	~20 s	1 rewritten: MainLayout.razor	Categories via EF Core, removed LoginView/GetRouteUrl references
Account/Admin stubs	~15 s	16 files modified: 15 Account + 1 Admin	Replaced with compilable stubs (not detected by auto-stub)
Build fix: _Imports	~5 s	1 modified: _Imports.razor	Removed invalid @rendermode InteractiveServer directive
Build fix: EF Core version	~5 s	1 modified: csproj	Changed to 10.0.0-preview.* wildcard for .NET 10 preview
Static assets	0 s	—	Already in wwwroot/ — no manual fix needed!
Layer 2 Total	~3 min 25 s	~50 files	—

Comparison with Run 5: Layer 2 dropped from ~7 min 20 s (60 files) to ~3 min 25 s (50 files). The biggest savings came from eliminating static asset relocation (wwwroot fix), reducing stub effort (6 auto-generated), and BWFC-aware SelectMethod guidance enabling faster page wiring.

7. Build Results

Build Round 1 — 4 Errors, 12 Warnings

NuGet authentication failure — Fritz.BlazorWebFormsComponents package not found (expected: local dev uses ProjectReference, not NuGet).

Fix: Replaced NuGet PackageReference with ProjectReference. Added EF Core + SQLite packages. Set up _Imports namespaces and App.razor CSS links.

Build Round 2 — 8 Errors, 134 Warnings

After csproj/models/pages fixes: @rendermode InteractiveServer in _Imports.razor is invalid — render mode cannot be set globally in _Imports.razor in .NET 10.

Fix: Removed @rendermode InteractiveServer from _Imports.razor.

Build Round 3 — 0 Errors, 4 Warnings

Clean compile. Only NuGet preview version resolution warnings remaining for EF Core packages.

Fix: Changed EF Core package versions to 10.0.0-preview.* wildcard.

Build Round 4 (Final) — Clean Build

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:04.40

Build Metric	Value
Target framework	net10.0
Fix rounds	4
Total build errors resolved	12 (4 + 8)
Final errors	0
Final warnings	0
Final build time	4.40 s

8. Gaps and Known Issues

Script Bugs Found

Bug	Severity	Description	Recommended Fix
@rendermode in _Imports.razor	Medium	Script scaffolds @rendermode InteractiveServer in _Imports.razor, which is invalid in .NET 10. Caused 8 build errors in Round 2.	Remove @rendermode InteractiveServer from _Imports.razor scaffold template. Set render mode in App.razor only.
Stub detection misses code-behind patterns	Low-Medium	Stub auto-generation scans .aspx markup for Session[, SignInManager, PayPal, Checkout keywords, but Account pages reference Identity only in .aspx.cs code-behind files. 15 Account + 1 Admin page were not auto-stubbed.	Extend stub detection to also scan .aspx.cs files for Identity/Auth patterns (SignInManager, UserManager, IdentityHelper, FormsAuthentication).

Patterns the Script Will Never Handle

These require semantic understanding beyond regex capabilities:

Pattern	Why Unreachable	Recommendation
Event handler migration	OnClick, OnSelectedIndexChanged → Blazor @onclick, EventCallback — requires understanding method signatures	Copilot-assisted rewrite per page
Page lifecycle methods	Page_Load, Page_PreInit → OnInitialized, OnParametersSet — context-dependent	Manual, guided by migration checklist
DI architecture	Choosing between @inject DbContext vs services vs repository pattern	Architectural decision per project
Identity provider swap	OWIN → ASP.NET Core Identity — full subsystem replacement	Manual using ASP.NET Core Identity scaffolding
Payment integrations	PayPal, Stripe, etc. — business logic tied to third-party APIs	Manual per integration

Patterns That Could Be Enhanced

Pattern	Current Handling	Potential Enhancement
Page.Title → <PageTitle>	Flagged as CodeBlock	Regex to wrap @(Title) in <PageTitle> component
Page base class swap	Not handled	Replace Page inheritance with ComponentBase in .razor.cs
Simple event handlers	Not handled	Strip OnClick="Handler" and emit TODO with handler signature
BundleConfig → link tags	Not handled	Parse BundleConfig.cs, emit <link>/<script> in App.razor

9. Recommendations

Immediate Script Fixes (for Run 7)

1. Fix @rendermode scaffold bug — Remove @rendermode InteractiveServer from the _Imports.razor template. This is the most impactful bug fix: it caused 8 build errors and a full build round in Run 6.

2. Extend stub detection to code-behind files — Scan .aspx.cs files for Identity/Auth patterns (SignInManager, UserManager, IdentityHelper, FormsAuthentication). This would auto-stub the 15 Account + 1 Admin pages that were missed, saving ~15 s of manual work.

Next Script Enhancements (Priority Order)

1. Page.Title → <PageTitle> conversion — Low complexity, high frequency. Regex can handle @(Title) and @(Page.Title) forms. Would eliminate 4+ manual fixes per project.

2. Simple event handler annotation — Strip OnClick="MethodName" attributes and emit @* TODO: Convert MethodName event handler *@. Extends the DI-hint pattern already proven with SelectMethod.

3. Page base class replacement — In generated .razor.cs files, replace : Page or : System.Web.UI.Page with : ComponentBase. Mechanical and safe.

What Should Remain Manual

• Identity/Auth — Too project-specific; ASP.NET Core Identity scaffolding tools already exist.
• EF6 → EF Core — Model conventions and seed strategies vary too widely.
• Business logic (checkout, payment, admin CRUD) — Requires domain understanding.
• Complex data binding — Nested expressions, arithmetic, method chains need human review.

Overall Assessment

The bwfc-migrate.ps1 script achieved a 55% total time reduction from Run 5 to Run 6, dropping from ~10 minutes to ~4 minutes 30 seconds. The four targeted enhancements all fired successfully, with SelectMethod BWFC-aware guidance proving the most impactful — it shifted the migration approach from replacing BWFC components with raw HTML to preserving them with proper Items parameter wiring. The script now handles 269 automated transforms, 79 static files (correctly placed in wwwroot/), and 6 auto-generated stubs, producing a project that requires only architectural decisions and data-layer wiring to reach a clean build.

The remaining ~3 min 25 s of manual work is dominated by inherently manual tasks: EF Core models (~45 s), page data binding (~60 s), and scaffold/csproj configuration (~30 s). These cannot be automated without understanding the application's data model and architecture. Two script bugs (the @rendermode scaffold issue and stub detection gap) are straightforward fixes that should be addressed before Run 7.

Verdict: Run 6 demonstrates that targeted, data-driven script enhancements yield outsized returns. The migration pipeline is now fast enough that the script phase (~4.6 s) is negligible compared to manual Layer 2 work (~205 s). Future optimization should focus on the two bug fixes identified, then on reducing the highest-cost manual categories: page data-binding wiring and csproj/scaffold configuration.

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Appendix: Full Timing Breakdown

Phase	Duration
Layer 1 (script)	4.58 s
Build 1 (initial — NuGet auth)	7.99 s
Layer 2 — csproj / scaffold	~30 s
Layer 2 — EF Core models	~45 s
Layer 2 — Services	~15 s
Layer 2 — Page data binding	~60 s
Layer 2 — Layout rewrite	~20 s
Layer 2 — Account/Admin stubs	~15 s
Layer 2 — Static assets	0 s (automated!)
Build 2 (post-fixes — @rendermode bug)	15.12 s
Layer 2 — _Imports rendermode fix	~5 s
Build 3 (clean — NuGet warnings only)	4.15 s
Layer 2 — EF Core version fix	~5 s
Build 4 (final — clean)	4.40 s
Layer 2 Total	~3 min 25 s
Total (all phases)	~4 min 30 s

See also: raw-data.md