---
id: wiki-2026-0508-aspnet-core
title: ASP.NET Core
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [ASP.NET Core, .NET Web, Kestrel, Minimal API]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [dotnet, csharp, web, backend]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: csharp
  framework: ASP.NET Core 9 / .NET 9
---

# ASP.NET Core

## 매 한 줄
> **"매 cross-platform high-performance 의 .NET 의 web framework"**. 매 Microsoft 의 2016 release 후 의 modular middleware pipeline + Kestrel server + DI built-in 의 design — 매 2026 의 .NET 9 의 native AOT, Minimal API, Blazor United, gRPC 의 first-class support 로 매 enterprise + cloud-native workload 의 dominant choice.

## 매 핵심

### 매 Architecture
- **Kestrel**: 매 cross-platform HTTP server (libuv → managed sockets).
- **Middleware pipeline**: 매 request 의 ordered chain — auth, logging, routing, endpoint.
- **DI container** (built-in): scoped/singleton/transient.
- **Configuration**: appsettings.json + env + secrets + Azure KeyVault 의 layered.
- **Hosting model**: Generic Host (`IHostBuilder`) → minimal `WebApplication`.

### 매 API styles
1. **Minimal API** (.NET 6+): top-level, lambda-based — small services 의 default.
2. **MVC controllers**: 매 conventional REST.
3. **Blazor Server / WASM / United** (.NET 8+): full-stack C# UI.
4. **gRPC**: HTTP/2, Protobuf — service-to-service.
5. **SignalR**: WebSocket / long-poll.

### 매 응용
1. REST API (Stripe, Shopify-style backends).
2. gRPC microservice mesh (.NET 9 의 native AOT 의 cold-start fast).
3. Blazor 의 internal admin panel.
4. Azure Functions / AWS Lambda (isolated worker).

## 💻 패턴

### Minimal API
```csharp
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddDbContext<AppDb>(o => o.UseNpgsql(builder.Configuration.GetConnectionString("Db")));
builder.Services.AddAuthentication().AddJwtBearer();

var app = builder.Build();
app.MapGet("/users/{id:int}", async (int id, AppDb db) =>
    await db.Users.FindAsync(id) is { } u ? Results.Ok(u) : Results.NotFound());
app.MapPost("/users", async (User u, AppDb db) => {
    db.Users.Add(u); await db.SaveChangesAsync();
    return Results.Created($"/users/{u.Id}", u);
});
app.Run();
```

### Middleware
```csharp
app.Use(async (ctx, next) => {
    var sw = Stopwatch.StartNew();
    await next();
    Console.WriteLine($"{ctx.Request.Path} {sw.ElapsedMilliseconds}ms");
});
```

### DI + scoped service
```csharp
builder.Services.AddScoped<IRepo, EfRepo>();
app.MapGet("/x", (IRepo r) => r.GetAll());
```

### Native AOT (.NET 9)
```xml
<PropertyGroup>
  <PublishAot>true</PublishAot>
  <InvariantGlobalization>true</InvariantGlobalization>
</PropertyGroup>
```
- 매 single-file binary, 매 cold-start <10ms, 매 reflection 의 limit.

### Authentication (JWT)
```csharp
builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(o => {
        o.TokenValidationParameters = new() {
            ValidIssuer = "https://issuer",
            ValidAudience = "api",
            IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secret))
        };
    });
app.UseAuthentication();
app.UseAuthorization();
app.MapGet("/me", (ClaimsPrincipal u) => u.Identity?.Name).RequireAuthorization();
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| Small service / prototype | Minimal API |
| Complex routing / filters | MVC Controllers |
| Service-to-service (internal) | gRPC |
| Real-time (chat, dashboard) | SignalR |
| Cold-start sensitive (lambda) | Native AOT + Minimal API |
| Full-stack C# | Blazor United |

**기본값**: 매 Minimal API + EF Core + JWT — 매 modern .NET 의 standard stack.

## 🔗 Graph
- 부모: [[.NET]] · [[C#]]
- 변형: [[ASP.NET MVC]] · [[Blazor]] · [[gRPC for .NET]]
- 응용: [[Azure Functions]] · [[Microservices]]
- Adjacent: [[Entity Framework Core]] · [[Kestrel]] · [[SignalR]]

## 🤖 LLM 활용
**언제**: Minimal API endpoint 의 생성, EF Core query 의 LINQ, middleware 의 boilerplate.
**언제 X**: 매 native AOT 의 reflection-heavy 의 third-party library 의 compatibility — 매 manual 의 verify.

## ❌ 안티패턴
- **Sync-over-async** (`.Result`, `.Wait()`): 매 thread pool 의 deadlock — 매 `await` 의 사용.
- **DbContext singleton**: 매 EF Core 의 not thread-safe — 매 scoped.
- **Middleware order 의 random**: 매 auth 의 routing 의 후 — 매 401 의 not enforced.
- **Returning IQueryable from controller**: 매 N+1, 매 connection 의 leak.

## 🧪 검증 / 중복
- Verified (learn.microsoft.com/aspnet/core, .NET 9 release notes).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — Minimal API + AOT + JWT patterns |