csharp-patterns

Name: csharp-patterns
Author: softspark

161stars21forks

How to install csharp-patterns?

softspark/ai-toolkit/csharp-patterns

$npx -y skills add softspark/ai-toolkit --skill csharp-patterns

Installs into the current project.

Summary

C#/.NET: LINQ, async/await, DI, records, nullable refs, ASP.NET Core, EF Core, MediatR. Triggers: C#, .NET, dotnet, ASP.NET, EF Core, LINQ, record type, IServiceCollection.

Files · 1

View on GitHub

SKILL.md

1	# C# / .NET Patterns
2
3	## Project Structure
4
5	### Solution Layout
6	```
7	MyApp.sln
8	Directory.Build.props # Shared build properties
9	Directory.Packages.props # Central package management
10	src/
11	MyApp.Api/ # ASP.NET Core host (Controllers, Middleware, Program.cs)
12	MyApp.Application/ # Use cases, MediatR handlers, Behaviors
13	MyApp.Domain/ # Entities, value objects, domain events
14	MyApp.Infrastructure/ # EF Core, external services
15	tests/
16	MyApp.UnitTests/
17	MyApp.IntegrationTests/
18	```
19
20	### Directory.Build.props
21	```xml
22	<Project>
23	<PropertyGroup>
24	<TargetFramework>net9.0</TargetFramework>
25	<Nullable>enable</Nullable>
26	<ImplicitUsings>enable</ImplicitUsings>
27	<TreatWarningsAsErrors>true</TreatWarningsAsErrors>
28	<EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
29	<AnalysisLevel>latest-recommended</AnalysisLevel>
30	</PropertyGroup>
31	</Project>
32	```
33
34	### Central Package Management (Directory.Packages.props)
35	```xml
36	<Project>
37	<PropertyGroup>
38	<ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
39	</PropertyGroup>
40	<ItemGroup>
41	<PackageVersion Include="MediatR" Version="12.4.1" />
42	<PackageVersion Include="FluentValidation" Version="11.11.0" />
43	<PackageVersion Include="Microsoft.EntityFrameworkCore" Version="9.0.0" />
44	</ItemGroup>
45	</Project>
46	```
47
48	---
49
50	## Idioms / Code Style
51
52	### Nullable Reference Types
53	```csharp
54	public class Order
55	{
56	public required string Id { get; init; }
57	public string? Notes { get; set; } // explicitly nullable
58	public required Customer Customer { get; init; } // never null
59	public string Summary => $"Order {Id}: {Notes ?? "no notes"}";
60	}
61	```
62
63	### Records
64	```csharp
65	public record Money(decimal Amount, string Currency)
66	{
67	public Money Add(Money other) => Currency != other.Currency
68	? throw new InvalidOperationException("Currency mismatch")
69	: this with { Amount = Amount + other.Amount };
70	}
71
72	public record CreateOrderRequest(string CustomerId, List<OrderLineDto> Lines);
73	public record OrderLineDto(string ProductId, int Quantity);
74	```
75
76	### Pattern Matching
77	```csharp
78	public decimal CalculateDiscount(Customer c) => c switch
79	{
80	{ Tier: CustomerTier.Gold, TotalSpent: > 10_000m } => 0.20m,
81	{ Tier: CustomerTier.Gold } => 0.15m,
82	{ Tier: CustomerTier.Silver } => 0.10m,
83	{ IsNewCustomer: true } => 0.05m,
84	_ => 0m
85	};
86
87	// List patterns (.NET 8+)
88	public string Describe(int[] v) => v switch
89	{
90	[] => "empty", [var x] => $"one: {x}", [var f, .., var l] => $"{f}..{l}",
91	};
92	```
93
94	### LINQ
95	```csharp
96	var activeUsers = users
97	.Where(u => u.IsActive)
98	.OrderByDescending(u => u.LastLogin)
99	.Select(u => new UserDto(u.Id, u.Name))
100	.ToList();
101	```
102
103	### Async/Await
104	```csharp
105	// Always: Async suffix, CancellationToken parameter, never .Result/.Wait()
106	public async Task<Order?> GetOrderAsync(string id, CancellationToken ct = default)
107	=> await _db.Orders.Include(o => o.Lines).FirstOrDefaultAsync(o => o.Id == id, ct);
108
109	// Parallel independent tasks
110	var ordersTask = _orderRepo.GetRecentAsync(ct);
111	var statsTask = _statsService.ComputeAsync(ct);
112	await Task.WhenAll(ordersTask, statsTask);
113	```
114
115	### Primary Constructors (C# 12)
116	```csharp
117	public class OrderService(IOrderRepository repo, ILogger<OrderService> logger, IPublisher pub)
118	{
119	public async Task<Order> CreateAsync(CreateOrderRequest req, CancellationToken ct)
120	{
121	logger.LogInformation("Creating order for {CustomerId}", req.CustomerId);
122	var order = Order.Create(req);
123	await repo.AddAsync(order, ct);
124	await pub.Publish(new OrderCreatedEvent(order.Id), ct);
125	return order;
126	}
127	}
128	```
129
130	---
131
132	## Error Handling
133
134	### Result Pattern
135	```csharp
136	public sealed class Result<T>
137	{
138	public T? Value { get; }
139	public Error? Error { get; }
140	public bool IsSuccess => Error is null;
141	private Result(T value) => Value = value;
142	private Result(Error error) => Error = error;
143	public static Result<T> Success(T value) => new(value);
144	public static Result<T> Failure(Error error) => new(error);
145	public TOut Match<TOut>(Func<T, TOut> ok, Func<Error, TOut> err) =>
146	IsSuccess ? ok(Value!) : err(Error!);
147	}
148	public record Error(string Code, string Message);
149	```
150
151	### FluentValidation + MediatR Pipeline
152	```csharp
153	public class CreateOrderValidator : AbstractValidator<CreateOrderRequest>
154	{
155	public CreateOrderValidator()
156	{
157	RuleFor(x => x.CustomerId).NotEmpty().MaximumLength(36);
158	RuleForEach(x => x.Lines).ChildRules(line =>

People who liked this also viewed

6 picks

Type

hyperframes-cliUse the HyperFrames CLI development loop: init, add, catalog, capture, lint, check, snapshot, compare, grade-compare, preview, play, present, beats, keyframes, single or batch render, publish, cloud, SkillsJul 2026262k37k
request-refactor-planSkills for Real Engineers. Straight from my .agents directory.SkillsJul 2026165k181k
analyze-projectRigor Analyze / Rigor Audit read-only skill for deep learning research repositories. Use when the user wants to read and understand a repository, inspect model structure and training or inference entrSkillsMay 2026161k507
explore-codeRigor Improve implementation leaf skill for auditable candidate implementation in deep learning research repositories. Use when the researcher explicitly authorizes exploratory work on an isolated braSkillsMay 2026161k507
ubiquitous-languageSkills for Real Engineers. Straight from my .agents directory.SkillsJul 2026160k181k
scaffold-exercisesSkills for Real Engineers. Straight from my .agents directory.SkillsJul 2026149k181k

csharp-patterns

161stars21forks

View on GitHub

How to install csharp-patterns?

softspark/ai-toolkit/csharp-patterns

$npx -y skills add softspark/ai-toolkit --skill csharp-patterns

Installs into the current project.

Summary

C#/.NET: LINQ, async/await, DI, records, nullable refs, ASP.NET Core, EF Core, MediatR. Triggers: C#, .NET, dotnet, ASP.NET, EF Core, LINQ, record type, IServiceCollection.

Files · 1

View on GitHub

SKILL.md

1	# C# / .NET Patterns
2
3	## Project Structure
4
5	### Solution Layout
6	```
7	MyApp.sln
8	Directory.Build.props # Shared build properties
9	Directory.Packages.props # Central package management
10	src/
11	MyApp.Api/ # ASP.NET Core host (Controllers, Middleware, Program.cs)
12	MyApp.Application/ # Use cases, MediatR handlers, Behaviors
13	MyApp.Domain/ # Entities, value objects, domain events
14	MyApp.Infrastructure/ # EF Core, external services
15	tests/
16	MyApp.UnitTests/
17	MyApp.IntegrationTests/
18	```
19
20	### Directory.Build.props
21	```xml
22	<Project>
23	<PropertyGroup>
24	<TargetFramework>net9.0</TargetFramework>
25	<Nullable>enable</Nullable>
26	<ImplicitUsings>enable</ImplicitUsings>
27	<TreatWarningsAsErrors>true</TreatWarningsAsErrors>
28	<EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
29	<AnalysisLevel>latest-recommended</AnalysisLevel>
30	</PropertyGroup>
31	</Project>
32	```
33
34	### Central Package Management (Directory.Packages.props)
35	```xml
36	<Project>
37	<PropertyGroup>
38	<ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
39	</PropertyGroup>
40	<ItemGroup>
41	<PackageVersion Include="MediatR" Version="12.4.1" />
42	<PackageVersion Include="FluentValidation" Version="11.11.0" />
43	<PackageVersion Include="Microsoft.EntityFrameworkCore" Version="9.0.0" />
44	</ItemGroup>
45	</Project>
46	```
47
48	---
49
50	## Idioms / Code Style
51
52	### Nullable Reference Types
53	```csharp
54	public class Order
55	{
56	public required string Id { get; init; }
57	public string? Notes { get; set; } // explicitly nullable
58	public required Customer Customer { get; init; } // never null
59	public string Summary => $"Order {Id}: {Notes ?? "no notes"}";
60	}
61	```
62
63	### Records
64	```csharp
65	public record Money(decimal Amount, string Currency)
66	{
67	public Money Add(Money other) => Currency != other.Currency
68	? throw new InvalidOperationException("Currency mismatch")
69	: this with { Amount = Amount + other.Amount };
70	}
71
72	public record CreateOrderRequest(string CustomerId, List<OrderLineDto> Lines);
73	public record OrderLineDto(string ProductId, int Quantity);
74	```
75
76	### Pattern Matching
77	```csharp
78	public decimal CalculateDiscount(Customer c) => c switch
79	{
80	{ Tier: CustomerTier.Gold, TotalSpent: > 10_000m } => 0.20m,
81	{ Tier: CustomerTier.Gold } => 0.15m,
82	{ Tier: CustomerTier.Silver } => 0.10m,
83	{ IsNewCustomer: true } => 0.05m,
84	_ => 0m
85	};
86
87	// List patterns (.NET 8+)
88	public string Describe(int[] v) => v switch
89	{
90	[] => "empty", [var x] => $"one: {x}", [var f, .., var l] => $"{f}..{l}",
91	};
92	```
93
94	### LINQ
95	```csharp
96	var activeUsers = users
97	.Where(u => u.IsActive)
98	.OrderByDescending(u => u.LastLogin)
99	.Select(u => new UserDto(u.Id, u.Name))
100	.ToList();
101	```
102
103	### Async/Await
104	```csharp
105	// Always: Async suffix, CancellationToken parameter, never .Result/.Wait()
106	public async Task<Order?> GetOrderAsync(string id, CancellationToken ct = default)
107	=> await _db.Orders.Include(o => o.Lines).FirstOrDefaultAsync(o => o.Id == id, ct);
108
109	// Parallel independent tasks
110	var ordersTask = _orderRepo.GetRecentAsync(ct);
111	var statsTask = _statsService.ComputeAsync(ct);
112	await Task.WhenAll(ordersTask, statsTask);
113	```
114
115	### Primary Constructors (C# 12)
116	```csharp
117	public class OrderService(IOrderRepository repo, ILogger<OrderService> logger, IPublisher pub)
118	{
119	public async Task<Order> CreateAsync(CreateOrderRequest req, CancellationToken ct)
120	{
121	logger.LogInformation("Creating order for {CustomerId}", req.CustomerId);
122	var order = Order.Create(req);
123	await repo.AddAsync(order, ct);
124	await pub.Publish(new OrderCreatedEvent(order.Id), ct);
125	return order;
126	}
127	}
128	```
129
130	---
131
132	## Error Handling
133
134	### Result Pattern
135	```csharp
136	public sealed class Result<T>
137	{
138	public T? Value { get; }
139	public Error? Error { get; }
140	public bool IsSuccess => Error is null;
141	private Result(T value) => Value = value;
142	private Result(Error error) => Error = error;
143	public static Result<T> Success(T value) => new(value);
144	public static Result<T> Failure(Error error) => new(error);
145	public TOut Match<TOut>(Func<T, TOut> ok, Func<Error, TOut> err) =>
146	IsSuccess ? ok(Value!) : err(Error!);
147	}
148	public record Error(string Code, string Message);
149	```
150
151	### FluentValidation + MediatR Pipeline
152	```csharp
153	public class CreateOrderValidator : AbstractValidator<CreateOrderRequest>
154	{
155	public CreateOrderValidator()
156	{
157	RuleFor(x => x.CustomerId).NotEmpty().MaximumLength(36);
158	RuleForEach(x => x.Lines).ChildRules(line =>

People who liked this also viewed

6 picks

Type