Shogi/.github/upgrades/scenarios/new-dotnet-version_a1d9f5/plan.md

# .NET 10.0 Upgrade Plan

## Table of Contents

- [Executive Summary](#executive-summary)
- [Migration Strategy](#migration-strategy)
- [Detailed Dependency Analysis](#detailed-dependency-analysis)
- [Project-by-Project Migration Plans](#project-by-project-migration-plans)
- [Package Update Reference](#package-update-reference)
- [Breaking Changes Catalog](#breaking-changes-catalog)
- [Testing & Validation Strategy](#testing--validation-strategy)
- [Risk Management](#risk-management)
- [Complexity & Effort Assessment](#complexity--effort-assessment)
- [Source Control Strategy](#source-control-strategy)
- [Success Criteria](#success-criteria)

---

## Executive Summary

### Scenario Description

Upgrade Shogi solution from .NET 8.0 to **.NET 10.0 (Long Term Support)**. The solution consists of 5 projects, with 4 .NET projects already targeting net10.0 and 1 SQL database project remaining on .NET Framework 4.7.2.

### Scope

**Projects in Scope:**
- **BoardRules\BoardRules.csproj** - Class library, already on net10.0 ✅
- **Shogi\Shogi.csproj** - ASP.NET Core web application, already on net10.0 ✅
- **Tests\AcceptanceTests\Shogi.AcceptanceTests.csproj** - Test project, already on net10.0 ✅
- **Tests\UnitTests\UnitTests.csproj** - Test project, already on net10.0 ✅
- **Shogi.Database\Shogi.Database.sqlproj** - SQL database project, remains on net472 (as expected)

**Current State:**
- 4 of 5 .NET projects already targeting net10.0
- All 14 NuGet packages already compatible with .NET 10.0
- No security vulnerabilities detected
- Total codebase: 5,753 lines of code across 64 files

**Target State:**
- Confirm all .NET projects are on net10.0
- Verify all packages are compatible
- Validate solution builds and all tests pass

### Selected Strategy

**All-At-Once Strategy** - All projects are already upgraded simultaneously.

**Rationale:**
- **Small solution** - Only 5 projects
- **Already migrated** - 4 projects already on net10.0
- **Simple dependency structure** - Clear hierarchy with no circular dependencies
- **All packages compatible** - All 14 NuGet packages support .NET 10.0
- **Zero risk** - No breaking changes, no security issues
- **Verification focus** - Primary task is to validate current state, not perform migration

### Complexity Assessment

**Discovered Metrics:**
- **Project count**: 5 (4 .NET projects + 1 SQL database project)
- **Dependency depth**: 1 (test projects depend on main Shogi project)
- **High-risk projects**: 0
- **Security vulnerabilities**: 0
- **Package updates required**: 0 (all already compatible)
- **Lines of code**: 5,753
- **API compatibility issues**: 0

**Classification**: **Simple** - Verification scenario

**Critical Issues**: None

### Recommended Approach

**Phase 1: Verification** - Confirm projects are on net10.0, packages are compatible
**Phase 2: Build & Test** - Ensure solution builds and all tests pass
**Phase 3: Documentation** - Update any remaining documentation references

This is primarily a **validation exercise** rather than an active migration, as the solution appears to have already been upgraded to .NET 10.0.

### Iteration Strategy

**Fast Verification Approach** (2-3 iterations):
- One iteration for all project details (since they're already upgraded)
- One iteration for validation and success criteria

---

## Migration Strategy

### Approach Selection

**Selected: All-At-Once Strategy (Verification Mode)**

This scenario is unique - it's not a traditional migration but a **verification** of an already-completed upgrade. All .NET projects already target net10.0.

### Strategy Rationale

**Why All-At-Once (Already Complete):**

1. **Small Solution** - Only 5 projects total (4 .NET projects)
2. **Already Migrated** - All .NET projects already on net10.0
3. **All Packages Compatible** - All 14 NuGet packages already support .NET 10.0
4. **No Breaking Changes** - Zero API compatibility issues detected
5. **Simple Dependencies** - Clear hierarchy, no circular dependencies
6. **Low Risk** - No security vulnerabilities, no code changes required

### All-At-Once Strategy Considerations

**Simultaneity**: Not applicable - upgrade already performed. Focus is on validation.

**Atomic Operation**: The original upgrade appears to have been completed atomically. Our task is to verify this state.

**No Intermediate States**: Already achieved - all projects are on target framework.

### Dependency-Based Ordering

While not needed for migration, validation will follow dependency order:

**Validation Order:**
1. **Standalone projects first**: BoardRules (no dependencies)
2. **Main application**: Shogi.csproj (depends on nothing within solution)
3. **Test projects last**: AcceptanceTests, UnitTests (depend on Shogi.csproj)

This ensures if issues exist, they're discovered at the lowest dependency level first.

### Parallel vs Sequential Execution

**Validation Approach**: Sequential validation following dependency order ensures clear error isolation. However, since all projects are already upgraded, parallel validation would also be safe.

**Recommended**: Sequential for clarity, parallel acceptable for speed.

### Phase Definitions

**Phase 1: Project File Verification**
- Confirm all .NET projects have `<TargetFramework>net10.0</TargetFramework>`
- Verify Shogi.Database.sqlproj correctly remains on net472
- Validate package references are compatible versions

**Phase 2: Build Validation**
- Restore NuGet packages
- Build entire solution
- Confirm zero errors, zero warnings

**Phase 3: Test Validation**
- Run acceptance tests
- Run unit tests
- Confirm all tests pass

**Phase 4: Documentation**
- Update any deployment documentation
- Confirm README reflects .NET 10.0
- Document verification results

---

## Detailed Dependency Analysis

### Dependency Graph Summary

The solution has a simple, clean dependency structure:

```
BoardRules.csproj (standalone, no dependencies)
    ↓
Shogi.csproj (main ASP.NET Core application)
    ↓
├── Shogi.AcceptanceTests.csproj (acceptance tests)
└── UnitTests.csproj (unit tests)

Shogi.Database.sqlproj (standalone SQL database project)
```

**Dependency Characteristics:**
- **Depth**: 1 level (test projects depend on main project)
- **Circular dependencies**: None
- **Standalone projects**: 2 (BoardRules, Shogi.Database)
- **Leaf nodes**: 2 (test projects)
- **Root node**: 1 (Shogi.csproj)

### Project Groupings by Migration Phase

Since all .NET projects are already on net10.0, grouping is for validation purposes only:

**Group 1: Standalone Libraries**
- BoardRules\BoardRules.csproj (already net10.0)
- Shogi.Database\Shogi.Database.sqlproj (remains net472 - SQL database project)

**Group 2: Main Application**
- Shogi\Shogi.csproj (already net10.0)

**Group 3: Test Projects**
- Tests\AcceptanceTests\Shogi.AcceptanceTests.csproj (already net10.0)
- Tests\UnitTests\UnitTests.csproj (already net10.0)

### Critical Path Identification

**No critical path** - All projects are already on target framework. The validation sequence is:

1. Verify standalone libraries (BoardRules)
2. Verify main application (Shogi)
3. Verify test projects build and pass

### Circular Dependency Analysis

**No circular dependencies detected** - Clean dependency tree.

---

## Project-by-Project Migration Plans

### Project: BoardRules\BoardRules.csproj

**Current State**:
- **Target Framework**: net10.0 ✅
- **SDK-Style**: True
- **Project Type**: Class Library
- **Dependencies**: 0 project dependencies, 0 NuGet packages
- **Dependants**: 0 (standalone library)
- **Lines of Code**: 120
- **Risk Level**: None

**Target State**:
- **Target Framework**: net10.0 (already achieved)
- **Package Count**: 0 (unchanged)

**Migration Steps**: ✅ Already Complete

This project is already on net10.0. No migration actions required.

**Validation Steps**:
1. ✅ Verify project file contains `<TargetFramework>net10.0</TargetFramework>`
2. ✅ Build project independently
3. ✅ Confirm zero build errors
4. ✅ Confirm zero build warnings

**Expected Breaking Changes**: None - project already on target framework

**Code Modifications**: None required

**Testing Strategy**:
- Build verification only (no test project exists for BoardRules)
- Confirm no compilation errors
- Verify as part of solution-wide build

**Validation Checklist**:
- [ ] Project builds successfully
- [ ] No build warnings
- [ ] No package dependency conflicts
- [ ] Compatible with dependent projects (none currently)

---

### Project: Shogi\Shogi.csproj

**Current State**:
- **Target Framework**: net10.0 ✅
- **SDK-Style**: True
- **Project Type**: ASP.NET Core Web Application
- **Dependencies**: 0 project dependencies (within solution)
- **Dependants**: 2 (Shogi.AcceptanceTests, UnitTests)
- **NuGet Packages**: 12 packages, all compatible with net10.0
- **Lines of Code**: 4,232
- **Risk Level**: None

**Target State**:
- **Target Framework**: net10.0 (already achieved)
- **Package Count**: 12 (all already compatible)

**Migration Steps**: ✅ Already Complete

This project is already on net10.0 with all packages at compatible versions.

**Package Updates**: None required - all packages already compatible

| Package | Current Version | Status |
|---------|----------------|---------|
| Dapper | 2.1.66 | ✅ Compatible |
| FluentValidation | 12.1.1 | ✅ Compatible |
| Microsoft.AspNetCore.Identity.EntityFrameworkCore | 10.0.1 | ✅ Compatible |
| Microsoft.AspNetCore.SignalR.Client | 10.0.1 | ✅ Compatible |
| Microsoft.EntityFrameworkCore.Design | 10.0.1 | ✅ Compatible |
| Microsoft.EntityFrameworkCore.InMemory | 10.0.1 | ✅ Compatible |
| Microsoft.EntityFrameworkCore.SqlServer | 10.0.1 | ✅ Compatible |
| Swashbuckle.AspNetCore | 10.1.0 | ✅ Compatible |
| System.Data.SqlClient | 4.9.0 | ✅ Compatible |

**Expected Breaking Changes**: None - project already on target framework, packages already compatible

**Code Modifications**: None required

**Configuration Updates**: None required - ASP.NET Core configuration already compatible

**Testing Strategy**:
- Build project successfully
- Execute acceptance tests (see Shogi.AcceptanceTests project)
- Execute unit tests (see UnitTests project)
- Verify application startup (if applicable)

**Validation Checklist**:
- [ ] Project builds successfully
- [ ] No build warnings
- [ ] All package dependencies restore successfully
- [ ] Entity Framework migrations compatible (if any)
- [ ] Acceptance tests pass
- [ ] Unit tests pass
- [ ] SignalR functionality works (if used)
- [ ] Identity/authentication works (if used)

---

### Project: Shogi.Database\Shogi.Database.sqlproj

**Current State**:
- **Target Framework**: net472
- **SDK-Style**: False
- **Project Type**: SQL Database Project (Classic)
- **Dependencies**: 0 project dependencies
- **Dependants**: 0
- **Lines of Code**: 0 (SQL project)
- **Risk Level**: None

**Target State**:
- **Target Framework**: net472 (unchanged - SQL database projects remain on .NET Framework)
- **No migration required**

**Migration Steps**: ⚠️ No Migration Required

SQL Database projects (.sqlproj) are build-time tools that generate database schema scripts. They typically remain on .NET Framework and do not need to be upgraded to .NET Core/.NET 10.0.

**Rationale for Not Upgrading**:
- SQL database projects are MSBuild-based schema definition tools
- They generate T-SQL scripts, not runtime executables
- .NET Framework 4.7.2 is appropriate for these projects
- No compatibility issues with the rest of the solution being on .NET 10.0

**Validation Steps**:
1. ✅ Confirm project remains on net472
2. ✅ Verify project builds successfully
3. ✅ Confirm database scripts generate correctly

**Expected Breaking Changes**: None

**Code Modifications**: None

**Testing Strategy**:
- Build verification only
- Confirm SQL scripts generate without errors
- Verify compatibility with SQL Server deployment targets

**Validation Checklist**:
- [ ] Project builds successfully on net472
- [ ] No build warnings
- [ ] Database schema scripts generate correctly
- [ ] No impact on .NET 10.0 projects in solution

---

### Project: Tests\AcceptanceTests\Shogi.AcceptanceTests.csproj

**Current State**:
- **Target Framework**: net10.0 ✅
- **SDK-Style**: True
- **Project Type**: xUnit Test Project (.NET Core)
- **Dependencies**: 1 project (Shogi.csproj)
- **Dependants**: 0
- **NuGet Packages**: 6 packages, all compatible with net10.0
- **Lines of Code**: 443
- **Risk Level**: None

**Target State**:
- **Target Framework**: net10.0 (already achieved)
- **Package Count**: 6 (all already compatible)

**Migration Steps**: ✅ Already Complete

This project is already on net10.0 with all test packages at compatible versions.

**Package Updates**: None required - all packages already compatible

| Package | Current Version | Status |
|---------|----------------|---------|
| coverlet.collector | 6.0.4 | ✅ Compatible |
| Microsoft.AspNetCore.Mvc.Testing | 10.0.1 | ✅ Compatible |
| Microsoft.EntityFrameworkCore.InMemory | 10.0.1 | ✅ Compatible |
| Microsoft.NET.Test.Sdk | 18.0.1 | ✅ Compatible |
| xunit | 2.9.3 | ✅ Compatible |
| xunit.runner.visualstudio | 3.1.5 | ✅ Compatible |

**Expected Breaking Changes**: None - project already on target framework

**Code Modifications**: None required

**Testing Strategy**:
- Build test project successfully
- Execute all acceptance tests
- Verify test discovery works correctly
- Confirm code coverage collection works (coverlet.collector)
- Validate ASP.NET Core test host compatibility (Microsoft.AspNetCore.Mvc.Testing)

**Validation Checklist**:
- [ ] Test project builds successfully
- [ ] No build warnings
- [ ] All tests are discovered
- [ ] All tests execute
- [ ] All tests pass
- [ ] Code coverage reporting works
- [ ] In-memory database tests function correctly

---

### Project: Tests\UnitTests\UnitTests.csproj

**Current State**:
- **Target Framework**: net10.0 ✅
- **SDK-Style**: True
- **Project Type**: xUnit Test Project (.NET Core)
- **Dependencies**: 1 project (Shogi.csproj)
- **Dependants**: 0
- **NuGet Packages**: 4 packages, all compatible with net10.0
- **Lines of Code**: 958
- **Risk Level**: None

**Target State**:
- **Target Framework**: net10.0 (already achieved)
- **Package Count**: 4 (all already compatible)

**Migration Steps**: ✅ Already Complete

This project is already on net10.0 with all test packages at compatible versions.

**Package Updates**: None required - all packages already compatible

| Package | Current Version | Status |
|---------|----------------|---------|
| coverlet.collector | 6.0.4 | ✅ Compatible |
| Microsoft.NET.Test.Sdk | 18.0.1 | ✅ Compatible |
| xunit | 2.9.3 | ✅ Compatible |
| xunit.runner.visualstudio | 3.1.5 | ✅ Compatible |

**Expected Breaking Changes**: None - project already on target framework

**Code Modifications**: None required

**Testing Strategy**:
- Build test project successfully
- Execute all unit tests
- Verify test discovery works correctly
- Confirm code coverage collection works (coverlet.collector)

**Validation Checklist**:
- [ ] Test project builds successfully
- [ ] No build warnings
- [ ] All tests are discovered
- [ ] All tests execute
- [ ] All tests pass
- [ ] Code coverage reporting works

---

## Package Update Reference

### Summary

**All packages are already compatible with .NET 10.0.** No package updates are required as part of this verification exercise.

### Complete Package Matrix

| Package | Current Version | Target Version | Projects | Update Reason |
|---------|----------------|----------------|----------|---------------|
| coverlet.collector | 6.0.4 | 6.0.4 (no change) | AcceptanceTests, UnitTests | ✅ Already compatible |
| Dapper | 2.1.66 | 2.1.66 (no change) | Shogi | ✅ Already compatible |
| FluentValidation | 12.1.1 | 12.1.1 (no change) | Shogi | ✅ Already compatible |
| Microsoft.AspNetCore.Identity.EntityFrameworkCore | 10.0.1 | 10.0.1 (no change) | Shogi | ✅ Already compatible |
| Microsoft.AspNetCore.Mvc.Testing | 10.0.1 | 10.0.1 (no change) | AcceptanceTests | ✅ Already compatible |
| Microsoft.AspNetCore.SignalR.Client | 10.0.1 | 10.0.1 (no change) | Shogi | ✅ Already compatible |
| Microsoft.EntityFrameworkCore.Design | 10.0.1 | 10.0.1 (no change) | Shogi | ✅ Already compatible |
| Microsoft.EntityFrameworkCore.InMemory | 10.0.1 | 10.0.1 (no change) | AcceptanceTests, Shogi | ✅ Already compatible |
| Microsoft.EntityFrameworkCore.SqlServer | 10.0.1 | 10.0.1 (no change) | Shogi | ✅ Already compatible |
| Microsoft.NET.Test.Sdk | 18.0.1 | 18.0.1 (no change) | AcceptanceTests, UnitTests | ✅ Already compatible |
| Swashbuckle.AspNetCore | 10.1.0 | 10.1.0 (no change) | Shogi | ✅ Already compatible |
| System.Data.SqlClient | 4.9.0 | 4.9.0 (no change) | Shogi | ✅ Already compatible |
| xunit | 2.9.3 | 2.9.3 (no change) | AcceptanceTests, UnitTests | ✅ Already compatible |
| xunit.runner.visualstudio | 3.1.5 | 3.1.5 (no change) | AcceptanceTests, UnitTests | ✅ Already compatible |

### Package Category Analysis

**ASP.NET Core Packages** (already at .NET 10.0 versions):
- Microsoft.AspNetCore.Identity.EntityFrameworkCore: 10.0.1
- Microsoft.AspNetCore.Mvc.Testing: 10.0.1
- Microsoft.AspNetCore.SignalR.Client: 10.0.1

**Entity Framework Core Packages** (already at .NET 10.0 versions):
- Microsoft.EntityFrameworkCore.Design: 10.0.1
- Microsoft.EntityFrameworkCore.InMemory: 10.0.1
- Microsoft.EntityFrameworkCore.SqlServer: 10.0.1

**Testing Packages** (already at compatible versions):
- Microsoft.NET.Test.Sdk: 18.0.1
- xunit: 2.9.3
- xunit.runner.visualstudio: 3.1.5
- coverlet.collector: 6.0.4

**Utility Packages** (already at compatible versions):
- Dapper: 2.1.66
- FluentValidation: 12.1.1
- Swashbuckle.AspNetCore: 10.1.0
- System.Data.SqlClient: 4.9.0

### Security Assessment

**No security vulnerabilities detected** in any packages. All packages are at secure, compatible versions for .NET 10.0.

---

## Breaking Changes Catalog

### Summary

**No breaking changes detected.** All projects are already on the target framework (net10.0) and all packages are at compatible versions.

### Framework Breaking Changes

**From .NET 8.0 to .NET 10.0**: Not applicable - projects already on net10.0.

If projects had been migrated from .NET 8.0 to .NET 10.0, the following categories would typically be reviewed:
- ASP.NET Core API changes (already handled)
- Entity Framework Core API changes (already handled)
- BCL (Base Class Library) changes (already handled)
- Runtime behavior changes (already handled)

### Package-Specific Breaking Changes

**No package breaking changes** - all packages are already at .NET 10.0-compatible versions.

### Configuration Changes

**No configuration changes required** - ASP.NET Core configuration is already compatible with .NET 10.0.

### Known Issues

**None identified** during assessment. All API compatibility checks passed.

### Areas Requiring Special Attention

Since this is a verification scenario, the following areas should be validated to ensure no issues were missed:

1. **Entity Framework Migrations**: Verify all EF migrations are compatible and functional
2. **SignalR Implementation**: Confirm SignalR hubs and clients work correctly
3. **Identity/Authentication**: Validate authentication and authorization flows
4. **Dependency Injection**: Ensure all service registrations are correct
5. **Middleware Pipeline**: Verify middleware order and functionality

### Breaking Changes by Project

**BoardRules.csproj**: None  
**Shogi.csproj**: None  
**Shogi.Database.sqlproj**: None (not migrating)  
**Shogi.AcceptanceTests.csproj**: None  
**UnitTests.csproj**: None

---

## Testing & Validation Strategy

### Overview

Testing strategy focuses on **verification** rather than migration validation, since all projects are already on the target framework.

### Multi-Level Testing

#### Phase 1: Project-Level Verification

**For Each Project:**

1. **BoardRules.csproj**
   - [ ] Project file verification: `<TargetFramework>net10.0</TargetFramework>` exists
   - [ ] Builds without errors
   - [ ] Builds without warnings
   - [ ] No package dependency conflicts

2. **Shogi.csproj**
   - [ ] Project file verification: `<TargetFramework>net10.0</TargetFramework>` exists
   - [ ] All 12 packages restore successfully
   - [ ] Builds without errors
   - [ ] Builds without warnings
   - [ ] Entity Framework migrations are intact
   - [ ] Configuration files are valid

3. **Shogi.Database.sqlproj**
   - [ ] Project file verification: remains on net472
   - [ ] Builds without errors
   - [ ] Database scripts generate successfully

4. **Shogi.AcceptanceTests.csproj**
   - [ ] Project file verification: `<TargetFramework>net10.0</TargetFramework>` exists
   - [ ] All 6 test packages restore successfully
   - [ ] Builds without errors
   - [ ] All tests are discovered
   - [ ] Tests can execute (actual pass/fail checked in Phase 3)

5. **UnitTests.csproj**
   - [ ] Project file verification: `<TargetFramework>net10.0</TargetFramework>` exists
   - [ ] All 4 test packages restore successfully
   - [ ] Builds without errors
   - [ ] All tests are discovered
   - [ ] Tests can execute (actual pass/fail checked in Phase 3)

#### Phase 2: Solution-Level Verification

**Complete Solution Build:**
- [ ] `dotnet restore` succeeds for entire solution
- [ ] `dotnet build` succeeds for entire solution
- [ ] Zero compilation errors across all projects
- [ ] Zero compilation warnings across all projects
- [ ] All project references resolve correctly
- [ ] All package dependencies resolve correctly

#### Phase 3: Functional Testing

**Acceptance Tests:**
- [ ] All acceptance tests execute
- [ ] All acceptance tests pass
- [ ] ASP.NET Core test host initializes correctly
- [ ] In-memory database tests function correctly
- [ ] Integration scenarios work as expected

**Unit Tests:**
- [ ] All unit tests execute
- [ ] All unit tests pass
- [ ] Code coverage collection works (if enabled)
- [ ] Test isolation is maintained

**Application Verification** (if applicable):
- [ ] Application starts successfully
- [ ] API endpoints are accessible
- [ ] Database connectivity works
- [ ] SignalR functionality operates correctly (if used)
- [ ] Identity/authentication flows work (if used)
- [ ] Swagger/OpenAPI documentation generates correctly

#### Phase 4: Deployment Verification (if applicable)

- [ ] Application can be published (`dotnet publish`)
- [ ] Published output is complete
- [ ] Published application runs in deployment environment
- [ ] Configuration transformations work correctly

### Test Execution Order

1. **Standalone projects first**: BoardRules, Shogi.Database
2. **Main application**: Shogi
3. **Test projects**: AcceptanceTests, UnitTests

This order follows dependency hierarchy to catch issues early.

### Success Criteria for Testing

**Build Success:**
- All 5 projects build without errors
- Zero build warnings
- All package references restore successfully

**Test Success:**
- All acceptance tests pass (100%)
- All unit tests pass (100%)
- Code coverage maintains or improves previous levels

**Functional Success:**
- Application starts and runs correctly
- All major features function as expected
- No runtime exceptions related to framework version

### Testing Tools

- **Build**: `dotnet build` (or Visual Studio)
- **Test Execution**: `dotnet test` (or Visual Studio Test Explorer)
- **Code Coverage**: coverlet.collector (already configured)
- **Package Management**: `dotnet restore` or NuGet Package Manager

### Regression Testing

Since projects are already upgraded, regression testing ensures no functionality was lost:

- Review test results history (if available)
- Compare current test pass rate with previous runs
- Validate critical business scenarios
- Check performance benchmarks (if established)

---

## Risk Management

### High-Level Risk Assessment

**Overall Risk Level**: **Very Low**

All .NET projects are already on the target framework (net10.0), all packages are compatible, and no security vulnerabilities were detected. This is a verification exercise, not an active migration.

### Risk Analysis

| Project | Risk Level | Description | Mitigation |
|---------|-----------|-------------|------------|
| BoardRules.csproj | ✅ None | Already on net10.0, standalone library, 120 LOC | Verify builds without errors |
| Shogi.csproj | ✅ None | Already on net10.0, all packages compatible, 4,232 LOC | Build and run acceptance/unit tests |
| Shogi.Database.sqlproj | ✅ None | Remains on net472 as expected for SQL database projects | No action required |
| Shogi.AcceptanceTests.csproj | ✅ None | Already on net10.0, test project, 443 LOC | Execute tests to confirm functionality |
| UnitTests.csproj | ✅ None | Already on net10.0, test project, 958 LOC | Execute tests to confirm functionality |

### Security Vulnerabilities

**No security vulnerabilities detected** across all NuGet packages. All packages are at compatible, secure versions for .NET 10.0.

### Contingency Plans

Since this is a verification scenario with minimal risk, contingency planning is straightforward:

**If build fails:**
- Review build errors for any environmental issues (SDK version, tooling)
- Confirm .NET 10.0 SDK is properly installed
- Check for missing NuGet package sources

**If tests fail:**
- Isolate failing tests to determine if related to framework version
- Review test execution environment
- Check for test infrastructure compatibility with .NET 10.0

**If package compatibility issues arise:**
- Re-assess package versions (assessment shows all compatible)
- Check for package source configuration issues
- Verify NuGet cache is not corrupted

### Rollback Plan

**Not applicable** - Since projects are already on net10.0, there is no migration to roll back. If issues are discovered, they would be addressed in-place rather than through rollback.

---

## Complexity & Effort Assessment

### Per-Project Complexity

| Project | Complexity | Dependencies | Risk | LOC | Notes |
|---------|-----------|--------------|------|-----|-------|
| BoardRules.csproj | Low | 0 | None | 120 | Standalone library, already upgraded |
| Shogi.csproj | Low | 0 | None | 4,232 | Main app, already upgraded, all packages compatible |
| Shogi.Database.sqlproj | Low | 0 | None | 0 | SQL database project, no migration needed |
| Shogi.AcceptanceTests.csproj | Low | 1 | None | 443 | Test project, already upgraded |
| UnitTests.csproj | Low | 1 | None | 958 | Test project, already upgraded |

**Overall Complexity**: **Low** - This is a verification scenario, not an active migration.

### Phase Complexity Assessment

**Phase 1: Project File Verification**
- **Complexity**: Low
- **Effort**: Minimal - automated verification of TargetFramework properties
- **Dependencies**: None

**Phase 2: Build Validation**
- **Complexity**: Low
- **Effort**: Minimal - standard build process
- **Dependencies**: Phase 1 complete

**Phase 3: Test Validation**
- **Complexity**: Low
- **Effort**: Minimal - execute existing test suites
- **Dependencies**: Phase 2 complete (solution must build)

**Phase 4: Documentation**
- **Complexity**: Low
- **Effort**: Minimal - update deployment docs if needed
- **Dependencies**: Phase 3 complete (tests must pass)

### Resource Requirements

**Skill Levels Required:**
- **Basic .NET knowledge** - Sufficient for verification activities
- **Build/test execution** - Standard CI/CD skills
- **No advanced migration expertise needed** - Projects already upgraded

**Parallel Capacity:**
- **Not applicable** - Verification is lightweight and can be done sequentially
- All validation activities can be performed by a single resource

### Total Effort Estimate

**Relative Complexity**: **Low**

**Effort Distribution:**
- Project file verification: Low
- Build validation: Low
- Test validation: Low
- Documentation updates: Low

**Note**: No real-time estimates provided. This is a verification exercise with minimal actual work required. The primary task is confirming that the existing state is correct and functional.

---

## Source Control Strategy

### Overview

Since this is a **verification exercise** rather than an active migration, source control strategy focuses on documenting the current state and ensuring any validation findings are properly tracked.

### Branching Strategy

**Current Branch**: `ssr` (as requested by user)

**Approach**: Work directly on the `ssr` branch, as no destructive changes are anticipated.

**Rationale**:
- Projects are already upgraded to net10.0
- Verification activities do not modify code
- Any documentation updates are additive, not breaking
- Low risk of needing to revert changes

**Alternative Approach** (if preferred):
- Create a verification branch from `ssr`
- Perform all validation activities
- Merge back to `ssr` after successful verification
- This provides isolation but adds overhead for minimal benefit

### Commit Strategy

**Approach**: Single commit after successful verification

**Recommended Commit Message**:
```
Verify .NET 10.0 upgrade - all projects confirmed on target framework

- Confirmed all .NET projects targeting net10.0
- Verified all 14 packages compatible with .NET 10.0
- Built solution successfully with zero errors/warnings
- Executed all tests (acceptance + unit) - all passing
- Validated Shogi.Database.sqlproj remains on net472 as expected
- No security vulnerabilities detected
- All-At-Once strategy already completed

Assessment: Low complexity, verification complete
```

**Alternative**: Multiple commits if validation reveals issues requiring fixes:
- Commit 1: "Verify project files and target frameworks"
- Commit 2: "Fix [specific issue] discovered during validation"
- Commit 3: "Confirm all tests pass on .NET 10.0"

### Code Review and Merge Process

**Review Requirements**: Minimal, since no code changes are expected

**Checklist for Review** (if formal review required):
- [ ] All projects verified on correct target framework
- [ ] Build succeeds with zero errors/warnings
- [ ] All tests pass (acceptance + unit)
- [ ] Documentation updated (if applicable)
- [ ] No new security vulnerabilities introduced
- [ ] Verification results documented

**Merge Criteria**:
- All validation checkpoints passed
- Tests are green
- No blocking issues discovered

### Repository State

**Current State** (as noted by user):
- **Branch**: `ssr`
- **Pending Changes**: Exist (user requested to proceed without git operations)

**Recommendation**:
Since user requested to skip git operations, work can proceed directly. However, best practice would be to:
1. Commit or stash pending changes before verification
2. Perform verification activities
3. Document results
4. Commit verification results separately

**User Preference**: Proceed without git operations - verification can be performed on current state.

### Documentation Updates

**Files to Update** (if applicable):
- README.md: Confirm .NET 10.0 is documented as target framework
- CHANGELOG.md: Add entry for .NET 10.0 verification
- Deployment documentation: Update any .NET version references
- CI/CD configuration: Ensure build pipelines target .NET 10.0 SDK

### All-At-Once Strategy Source Control Guidance

Since the All-At-Once upgrade appears to have already been completed (all projects simultaneously updated to net10.0), the source control strategy is retrospective:

**Original Migration** (already completed):
- Appears to have been done atomically (all projects upgraded together)
- Single-commit approach was likely used
- All package updates applied simultaneously
- Clean result with no intermediate states

**Current Verification**:
- Confirm the atomic upgrade was successful
- Validate no issues remain from the original migration
- Document the current verified state

---

## Success Criteria

### Technical Criteria

**Project Framework Verification**: ✅ Target Met (Pending Validation)
- [ ] All .NET projects target net10.0:
  - [ ] BoardRules\BoardRules.csproj: `<TargetFramework>net10.0</TargetFramework>`
  - [ ] Shogi\Shogi.csproj: `<TargetFramework>net10.0</TargetFramework>`
  - [ ] Tests\AcceptanceTests\Shogi.AcceptanceTests.csproj: `<TargetFramework>net10.0</TargetFramework>`
  - [ ] Tests\UnitTests\UnitTests.csproj: `<TargetFramework>net10.0</TargetFramework>`
- [ ] Shogi.Database\Shogi.Database.sqlproj correctly remains on net472

**Package Compatibility**: ✅ Target Met (Pending Validation)
- [ ] All 14 NuGet packages verified at .NET 10.0-compatible versions
- [ ] Zero packages with security vulnerabilities
- [ ] All package references restore successfully
- [ ] No package dependency conflicts

**Build Success**: 🔄 Requires Validation
- [ ] `dotnet restore` succeeds for entire solution
- [ ] `dotnet build` succeeds for entire solution (exit code 0)
- [ ] Zero compilation errors across all 5 projects
- [ ] Zero compilation warnings across all 5 projects
- [ ] All project references resolve correctly

**Test Success**: 🔄 Requires Validation
- [ ] All acceptance tests execute
- [ ] All acceptance tests pass (100% pass rate)
- [ ] All unit tests execute
- [ ] All unit tests pass (100% pass rate)
- [ ] Code coverage collection works (coverlet.collector)

**Runtime Success**: 🔄 Requires Validation (if applicable)
- [ ] Application starts successfully
- [ ] No runtime exceptions related to .NET version
- [ ] All major features functional
- [ ] Database connectivity works
- [ ] SignalR functionality operates (if used)
- [ ] Identity/authentication works (if used)

### Quality Criteria

**Code Quality**: ✅ Already Maintained
- [ ] No new code quality issues introduced
- [ ] Existing code quality maintained
- [ ] No deprecated API usage warnings

**Test Coverage**: ✅ Already Maintained
- [ ] Test coverage maintained at previous levels
- [ ] No loss of test coverage
- [ ] All existing tests still relevant

**Documentation**: 🔄 Requires Update (if applicable)
- [ ] README updated to reference .NET 10.0 (if not already)
- [ ] Deployment documentation reflects .NET 10.0
- [ ] CI/CD pipeline documentation updated
- [ ] CHANGELOG includes .NET 10.0 verification entry

### Process Criteria

**All-At-Once Strategy Compliance**: ✅ Already Applied
- [ ] All-At-Once approach was used (all projects upgraded simultaneously)
- [ ] No intermediate states exist
- [ ] All projects on same target framework (net10.0)
- [ ] Atomic upgrade principle followed

**Verification Methodology**: 🔄 Requires Execution
- [ ] Systematic project-by-project verification performed
- [ ] Solution-level build verification performed
- [ ] Comprehensive test execution completed
- [ ] Results documented

**Source Control**: 🔄 Conditional
- [ ] Verification results committed (if git operations performed)
- [ ] Documentation updates committed (if applicable)
- [ ] Clean working directory (or documented pending changes)

### Completion Definition

**The verification is complete and successful when:**

1. ✅ **All .NET projects confirmed on net10.0**
   - Project files inspected and verified
   - Shogi.Database.sqlproj confirmed on net472 (as expected)

2. ✅ **All packages confirmed compatible**
   - 14 packages verified at compatible versions
   - Zero security vulnerabilities
   - No deprecated or obsolete packages

3. ✅ **Solution builds successfully**
   - Restore succeeds
   - Build succeeds with zero errors
   - Zero build warnings

4. ✅ **All tests pass**
   - Acceptance tests: 100% pass
   - Unit tests: 100% pass
   - No skipped or failing tests

5. ✅ **Application runs correctly** (if applicable)
   - Starts without errors
   - Core functionality verified
   - No runtime exceptions

6. ✅ **Documentation updated** (if applicable)
   - Version references corrected
   - Deployment guides updated
   - Verification documented

### Acceptance Sign-Off

**Criteria for Final Acceptance:**

- All technical criteria marked complete ✅
- All quality criteria marked complete ✅
- All process criteria marked complete ✅
- No blocking issues remain
- Verification results documented and committed

**Final Deliverable**: Verified .NET 10.0 solution with documented validation results, all projects on target framework, all tests passing, ready for deployment.

### Notes

This is a **verification scenario**, not an active migration. Success is measured by confirming the current state (net10.0) is correct and functional, not by completing migration activities. The assessment indicates the upgrade has already been completed successfully; verification activities will confirm this assessment is accurate.