Table Of Contents

• Chapter 1 : Introduction Understanding C#, .Net, and Your First Setup

  • 1.1 What is .Net
  • 1.1.1 The .Net Framework Windows only legacy
  • 1.1.2 The .Net Core cross platform modern
  • 1.1.3 The .Net 5, 6, 7, 8 unified platform
  • 1.1.4 The .Net Standard API compatibility contract
  • 1.2 Installing the .Net SDK
  • 1.2.1 Download from dotnet.microsoft.com
  • 1.2.2 Verify installation with dotnet info
  • 1.2.3 SDK vs Runtime
  • 1.3 Project structure
  • 1.3.1 csproj file XML format package references
  • 1.3.2 Program.cs entry point
  • 1.3.3 appsettings.json configuration
  • 1.3.4 obj and bin folders
  • 1.4 The dotnet CLI
  • 1.4.1 dotnet new create project from template
  • 1.4.2 dotnet build compile
  • 1.4.3 dotnet run build and execute
  • 1.4.4 dotnet test run unit tests
  • 1.4.5 dotnet publish create deployable output
  • 1.5 Top level statements C# 9 and later
  • 1.5.1 No explicit Main method
  • 1.5.2 Implicit using directives
  • 1.5.3 When to use vs traditional Main
  • 1.6 Your first console app Hello World
  • 1.6.1 Create project dotnet new console n HelloWorld
  • 1.6.2 Write Console.WriteLine Hello World
  • 1.6.3 Run and observe output
  • 1.7 Project Command Line Greeting Tool
  • 1.7.1 Idea ask name and favourite colour print greeting
  • 1.7.2 Folder structure GreetingTool Program.cs
  • 1.7.3 Steps ask name ask colour print personalised greeting
• Chapter 2 : Primitive Types and Basic Syntax

  • 2.1 Value types
  • 2.1.1 Integral types
  • 2.2 Reference types
  • 2.2.1 string
  • 2.2.2 object
  • 2.2.3 dynamic
  • 2.3 Variables and constants
  • 2.3.1 Declaration type variableName
  • 2.3.2 Initialisation int x = 5
  • 2.3.3 Type inference with var
  • 2.3.4 Constants const double Pi = 3.14
  • 2.3.5 Read only fields
  • 2.4 String interpolation
  • 2.4.1 Syntax Hello name
  • 2.4.2 Formatting value format
  • 2.4.3 Escape sequences for literal brace
  • 2.5 Basic IO
  • 2.5.1 Console.WriteLine line
  • 2.5.2 Console.Write no newline
  • 2.5.3 Console.ReadLine returns string
  • 2.5.4 Console.ReadKey single character
  • 2.6 Type conversion
  • 2.6.1 Implicit conversion
  • 2.6.2 Explicit cast
  • 2.6.3 Convert class
  • 2.6.4 Parse and TryParse
  • 2.7 Project Simple Calculator
• Chapter 3 : Control Flow and Operators

  • 3.1 Conditional statements
  • 3.1.1 if statement
  • 3.1.2 else if chain
  • 3.1.3 else clause
  • 3.1.4 nested if
  • 3.2 switch statement
  • 3.2.1 switch with constant patterns
  • 3.2.2 switch with pattern matching C# 7 and later
  • 3.2.3 when guards
  • 3.2.4 goto case rare
  • 3.3 Switch expressions C# 8 and later
  • 3.3.1 syntax
  • 3.3.2 discard pattern
  • 3.4 Loops
  • 3.4.1 for loop
  • 3.4.2 foreach
  • 3.4.3 while
  • 3.4.4 do while
  • 3.5 Loop control
  • 3.5.1 break
  • 3.5.2 continue
  • 3.5.3 return
  • 3.5.4 goto avoid
  • 3.6 Operators
  • 3.6.1 Arithmetic
  • 3.6.2 Assignment
  • 3.6.3 Logical
  • 3.6.4 Comparison
  • 3.6.5 Null coalescing
  • 3.6.6 Null conditional
  • 3.6.7 Ternary
  • 3.6.8 Bitwise
  • 3.7 Project Number Guessing Game
• Chapter 4 : Object Oriented Programming OOP Deep Dive

  • 4.1 Classes and objects
  • 4.1.1 Class definition
  • 4.1.2 Instantiation
  • 4.1.3 Fields
  • 4.1.4 Properties
  • 4.1.5 Methods
  • 4.2 Encapsulation
  • 4.2.1 Access modifiers
  • 4.2.2 Property accessors
  • 4.2.3 Auto implemented properties
  • 4.3 Inheritance
  • 4.3.1 Base class and derived class
  • 4.3.2 base keyword
  • 4.3.3 Sealed classes
  • 4.3.4 virtual and override methods
  • 4.3.5 abstract classes and methods
  • 4.3.6 Hiding members with new
  • 4.4 Polymorphism
  • 4.4.1 Compile time overloading
  • 4.4.2 Runtime virtual override
  • 4.4.3 is and as operators
  • 4.5 Interfaces
  • 4.5.1 Interface definition
  • 4.5.2 Implementing an interface
  • 4.5.3 Explicit interface implementation
  • 4.5.4 Default interface methods C# 8 and later
  • 4.6 Static classes and members
  • 4.6.1 Static fields methods properties
  • 4.6.2 Static constructor
  • 4.6.3 Static class cannot be instantiated
  • 4.7 Project Library Management System console
• Chapter 5 : Design Patterns for Backend Development

  • 5.1 Creational patterns
  • 5.1.1 Factory Method
  • 5.1.2 Abstract Factory
  • 5.1.3 Singleton
  • 5.1.4 Builder
  • 5.1.5 Prototype
  • 5.2 Structural patterns
  • 5.2.1 Adapter
  • 5.2.2 Proxy
  • 5.2.3 Decorator
  • 5.2.4 Facade
  • 5.2.5 Bridge
  • 5.2.6 Composite
  • 5.2.7 Flyweight
  • 5.3 Behavioural patterns
  • 5.3.1 Strategy
  • 5.3.2 Command
  • 5.3.3 Observer
  • 5.3.4 Chain of Responsibility
  • 5.3.5 Mediator
  • 5.3.6 Memento
  • 5.3.7 State
  • 5.3.8 Template Method
  • 5.3.9 Visitor
  • 5.4 Architectural patterns for backend
  • 5.4.1 Repository
  • 5.4.2 Middleware
  • 5.4.3 Dependency Injection
  • 5.5 Project Discount Strategy System
• Chapter 6 : Advanced Type System

  • 6.1 Records
  • 6.1.1 record class
  • 6.1.2 record struct
  • 6.1.3 Positional records
  • 6.1.4 with expressions
  • 6.1.5 Value based equality
  • 6.2 Structs
  • 6.2.1 struct
  • 6.2.2 readonly struct
  • 6.2.3 ref struct
  • 6.2.4 When to use struct vs class
  • 6.3 Enums
  • 6.3.1 enum definition
  • 6.3.2 Underlying type
  • 6.3.3 Flags enum
  • 6.3.4 Enum Parse and Enum GetValues
  • 6.4 Nullable reference types C# 8 and later
  • 6.4.1 string question mark nullable reference
  • 6.4.2 Nullable annotation context
  • 6.4.3 Null forgiving operator
  • 6.4.4 Nullable warnings
  • 6.5 Pattern matching
  • 6.5.1 Constant pattern
  • 6.5.2 Type pattern
  • 6.5.3 Property pattern
  • 6.5.4 Positional pattern
  • 6.5.5 List patterns C# 11
  • 6.5.6 var pattern
  • 6.6 Project Immutable Person Record with Validation
• Chapter 7 : Delegates Events and Lambdas

  • 7.1 Delegates
  • 7.1.1 Declaration
  • 7.1.2 Instantiation and invocation
  • 7.1.3 Multicast delegates
  • 7.1.4 Generic delegates Action Func Predicate
  • 7.2 Events
  • 7.2.1 event keyword
  • 7.2.2 Subscribing and unsubscribing
  • 7.2.3 Event invocation
  • 7.2.4 Standard pattern EventHandler and EventArgs
  • 7.3 Lambda expressions
  • 7.3.1 Syntax
  • 7.3.2 Statement lambdas
  • 7.3.3 Capturing outer variables closures
  • 7.3.4 Expression trees
  • 7.4 Anonymous functions
  • 7.4.1 delegate keyword pre lambda
  • 7.4.2 Comparison with lambdas
  • 7.5 Project Button Click Simulator Event
• Chapter 8 : LINQ Language Integrated Query

  • 8.1 Query syntax vs method syntax
  • 8.1.1 Query syntax
  • 8.1.2 Method syntax
  • 8.1.3 Mixing both
  • 8.2 Deferred vs immediate execution
  • 8.2.1 Deferred operators
  • 8.2.2 Immediate operators
  • 8.2.3 Streaming vs buffering operators
  • 8.3 LINQ to Objects LINQ to XML LINQ to Entities
  • 8.3.1 In memory collections
  • 8.3.2 XML
  • 8.3.3 EF Core SQL translation
  • 8.4 Common operators
  • 8.4.1 Filtering
  • 8.4.2 Projection
  • 8.4.3 Ordering
  • 8.4.4 Grouping
  • 8.4.5 Joining
  • 8.4.6 Aggregation
  • 8.4.7 Element operators
  • 8.4.8 Set operators
  • 8.4.9 Quantifiers
  • 8.4.10 Partitioning
  • 8.5 Project Employee Data Analysis
• Chapter 9 : Asynchronous Programming async await

  • 9.1 Task based Asynchronous Pattern TAP
  • 9.1.1 Task no result
  • 9.1.2 Task T result
  • 9.1.3 ValueTask and ValueTask T for performance
  • 9.2 async and await
  • 9.2.1 Marking method async
  • 9.2.2 await unwraps the result
  • 9.2.3 Compiler transformation into state machine
  • 9.3 Return types of async methods
  • 9.3.1 Task for void async
  • 9.3.2 Task T for returning value
  • 9.3.3 void only for event handlers avoid
  • 9.4 Asynchronous streams
  • 9.4.1 IAsyncEnumerable T
  • 9.4.2 await foreach
  • 9.4.3 await using asynchronous disposable
  • 9.5 Avoiding async void
  • 9.5.1 Exceptions cannot be caught
  • 9.5.2 Hard to test
  • 9.6 ConfigureAwait false
  • 9.6.1 Avoid capturing original SynchronizationContext
  • 9.6.2 Use in library code
  • 9.7 Cancellation tokens
  • 9.7.1 CancellationTokenSource
  • 9.7.2 CancellationToken
  • 9.7.3 ThrowIfCancellationRequested
  • 9.7.4 Cooperative cancellation
  • 9.8 Project Async Weather Fetcher
• Chapter 10 : Memory Management and Performance

  • 10.1 Garbage collection
  • 10.1.1 Generations 0, 1, 2
  • 10.1.2 Workstation GC vs Server GC
  • 10.1.3 Background GC
  • 10.1.4 Large Object Heap LOH
  • 10.1.5 Pinned objects
  • 10.2 IDisposable
  • 10.2.1 Unmanaged resources
  • 10.2.2 Dispose pattern
  • 10.2.3 using statement
  • 10.2.4 await using and IAsyncDisposable
  • 10.3 Span T and Memory T
  • 10.3.1 Stack only Span T
  • 10.3.2 Memory T for heap or async
  • 10.3.3 ArrayPool T for renting buffers
  • 10.4 Benchmarking
  • 10.4.1 BenchmarkDotNet
  • 10.4.2 Benchmark and MemoryDiagnoser attributes
  • 10.4.3 Running benchmarks avoiding common pitfalls
  • 10.5 Project Benchmark String Concatenation vs StringBuilder
• Chapter 11 : Generics and Constraints

  • 11.1 Generic classes
  • 11.1.1 Syntax
  • 11.1.2 Type parameters naming T, TKey, TValue
  • 11.2 Generic methods
  • 11.2.1 T MyMethod T param
  • 11.2.2 Type inference at call site
  • 11.3 Generic interfaces
  • 11.3.1 interface IRepository T
  • 11.3.2 Covariance out T and contravariance in T
  • 11.4 Constraints
  • 11.4.1 where T struct value type
  • 11.4.2 where T class reference type
  • 11.4.3 where T new parameterless constructor
  • 11.4.4 where T BaseClass base class constraint
  • 11.4.5 where T IMyInterface interface constraint
  • 11.4.6 where T unmanaged no references
  • 11.4.7 Multiple constraints
  • 11.5 Project Generic Repository Simulator
• Chapter 12 : Exceptions and Error Handling

  • 12.1 try catch finally
  • 12.1.1 Catching specific exception types
  • 12.1.2 Multiple catch blocks
  • 12.1.3 finally for cleanup
  • 12.2 Exception filters
  • 12.2.1 catch with when condition
  • 12.3 Custom exceptions
  • 12.3.1 Derive from Exception or ApplicationException
  • 12.3.2 Serialisation constructor
  • 12.3.3 Adding custom properties
  • 12.4 ExceptionDispatchInfo
  • 12.4.1 Capturing and rethrowing with original stack trace
  • 12.5 Global exception handling
  • 12.5.1 ASP.NET Core middleware
  • 12.5.2 AppDomain UnhandledException
  • 12.5.3 TaskScheduler UnobservedTaskException
  • 12.6 Project Safe File Reader with Retry
• Chapter 13 : Reflection Attributes and Source Generators

  • 13.1 Reflection
  • 13.1.1 Type class
  • 13.1.2 Assembly loading and scanning
  • 13.1.3 MemberInfo MethodInfo PropertyInfo
  • 13.1.4 Invoking methods dynamically
  • 13.2 Custom attributes
  • 13.2.1 Attribute class AttributeUsage
  • 13.2.2 Applying attributes to targets
  • 13.2.3 Reading attributes with reflection
  • 13.3 Source generators
  • 13.3.1 What are source generators
  • 13.3.2 Incremental generators
  • 13.3.3 Use cases compile time code performance
  • 13.3.4 Difference from reflection no runtime overhead
  • 13.4 Project Attribute Based Validation Engine
• Chapter 14 : Modern C# Features for Backend

  • 14.1 init only setters
  • 14.1.1 Immutable objects after construction
  • 14.1.2 Object initialiser with init
  • 14.2 Required members C# 11
  • 14.2.1 required keyword
  • 14.2.2 Constructor ensures required properties set
  • 14.3 Record types emphasis
  • 14.4 Interpolated string handlers
  • 14.4.1 Performance optimisation for logging
  • 14.4.2 InterpolatedStringHandler struct
  • 14.5 Caller info attributes
  • 14.5.1 CallerMemberName
  • 14.5.2 CallerArgumentExpression
  • 14.5.3 CallerFilePath and CallerLineNumber
  • 14.6 Project Logging Helper with Caller Info
• Chapter 15 : Testing and Mocking

  • 15.1 Unit testing frameworks
  • 15.1.1 xUnit Fact Theory InlineData
  • 15.1.2 NUnit Test TestCase
  • 15.1.3 MSTest
  • 15.2 Mocking libraries
  • 15.2.1 Moq Mock Setup Verify
  • 15.2.2 NSubstitute Substitute.For
  • 15.2.3 FakeItEasy
  • 15.3 Test doubles
  • 15.3.1 Stub
  • 15.3.2 Mock
  • 15.3.3 Fake
  • 15.4 Integration testing
  • 15.4.1 WebApplicationFactory TStartup
  • 15.4.2 In memory database with EF Core
  • 15.4.3 HttpClient for testing endpoints
  • 15.5 Project Testing a Calculator Service with Moq
• Chapter 16 : Logging Diagnostics and Configuration

  • 16.1 Logging
  • 16.1.1 ILogger T interface
  • 16.1.2 Log levels Trace Debug Information Warning Error Critical
  • 16.1.3 Structured logging with Serilog NLog
  • 16.1.4 Enrichment and sinks console file Elasticsearch
  • 16.2 Configuration
  • 16.2.1 IConfiguration and configuration providers
  • 16.2.2 JSON files appsettings.json
  • 16.2.3 Environment variables
  • 16.2.4 User secrets for development only
  • 16.2.5 Command line arguments
  • 16.3 Options pattern
  • 16.3.1 IOptions T singleton no reload
  • 16.3.2 IOptionsSnapshot T scoped reload on change
  • 16.3.3 IOptionsMonitor T singleton with change notifications
  • 16.3.4 Configure T and PostConfigure
  • 16.4 Project Configurable App with Serilog
• Chapter 17 : Dependency Injection Deep Dive

  • 17.1 Service lifetimes
  • 17.1.1 Singleton one instance for entire app
  • 17.1.2 Scoped one per HTTP request or scope
  • 17.1.3 Transient new instance every time
  • 17.2 Registration methods
  • 17.2.1 AddSingleton AddScoped AddTransient
  • 17.2.2 Factory delegates
  • 17.2.3 Open generic registrations
  • 17.3 Service resolution
  • 17.3.1 Constructor injection preferred
  • 17.3.2 IServiceProvider directly
  • 17.3.3 IServiceScopeFactory for creating scopes
  • 17.4 Decorator pattern with DI
  • 17.4.1 Using AddScoped to wrap a service
  • 17.4.2 Scrutor library for decorators
  • 17.5 Project DI Lifetime Demonstrator
• Chapter 18 : Interop and Low Level APIs

  • 18.1 PInvoke
  • 18.1.1 DllImport attribute legacy
  • 18.1.2 LibraryImport source generator .Net 7 and later
  • 18.1.3 Marshalling strings structs pointers
  • 18.2 Unsafe code
  • 18.2.1 unsafe context
  • 18.2.2 Pointers
  • 18.2.3 fixed statement to pin managed objects
  • 18.2.4 stackalloc allocate on stack
  • 18.3 Memory mapped files
  • 18.3.1 MemoryMappedFile.CreateFromFile
  • 18.3.2 MemoryMappedViewAccessor
  • 18.4 Marshal class
  • 18.4.1 Marshal.AllocHGlobal unmanaged memory
  • 18.4.2 Marshal.StructureToPtr
  • 18.4.3 Marshal.PtrToStructure
  • 18.5 Project Call Windows MessageBox via PInvoke
• Chapter 19 : Backend Specific Patterns

  • 19.1 Middleware pipeline
  • 19.1.1 Use short circuiting
  • 19.1.2 Run terminal middleware
  • 19.1.3 Map branching
  • 19.1.4 Order of middleware
  • 19.2 Request delegates
  • 19.2.1 RequestDelegate signature
  • 19.2.2 Inline middleware with Use
  • 19.3 Custom middleware
  • 19.3.1 Class with InvokeAsync method
  • 19.3.2 Injecting services scoped singleton
  • 19.3.3 Calling next context
  • 19.4 Project Custom Request Logging Middleware
• Chapter 20 : Code Quality and Tooling

  • 20.1 Roslyn analyzers
  • 20.1.1 FxCop legacy and Microsoft.CodeAnalysis.NetAnalyzers
  • 20.1.2 StyleCop naming layout
  • 20.1.3 SonarAnalyzer security bugs
  • 20.2 Formatting
  • 20.2.1 editorconfig file
  • 20.2.2 dotnet format command
  • 20.2.3 IDE integration VS Rider VS Code
  • 20.3 Pre commit hooks
  • 20.3.1 Husky.NET or simple bash scripts
  • 20.3.2 Running dotnet format and dotnet test before commit
  • 20.4 Project Enforce Coding Standards with editorconfig
• Chapter 21 : CLR Internals and Diagnostics

  • 21.1 JIT compilation
  • 21.1.1 Tiered compilation
  • 21.1.2 ReadyToRun R2R ahead of time
  • 21.1.3 Cross gen single file Native AOT
  • 21.2 Diagnostic tools
  • 21.2.1 dotnet trace runtime events profiling
  • 21.2.2 dotnet dump heap analysis crash dumps
  • 21.2.3 dotnet counters performance counters
  • 21.2.4 dotnet gcdump GC heap snapshots
  • 21.3 Event listeners
  • 21.3.1 EventSource custom events
  • 21.3.2 EventListener consume events
  • 21.3.3 DiagnosticSource for library instrumentation
  • 21.4 Project Collect GC Events with EventListener
• Chapter 22 : Low Level Concurrency and Lock Free Code

  • 22.1 Threading basics recap
  • 22.1.1 System.Threading.Thread
  • 22.1.2 ThreadPool
  • 22.1.3 Task as higher level abstraction
  • 22.2 Lock free primitives
  • 22.2.1 Interlocked class
  • 22.2.2 Volatile prevent compiler optimisations
  • 22.2.3 MemoryBarrier rarely needed directly
  • 22.3 Lightweight synchronisation
  • 22.3.1 SpinLock when lock held for short time
  • 22.3.2 SpinWait hybrid spinning
  • 22.3.3 Lazy T with thread safe initialisation
  • 22.3.4 LazyInitializer static helpers
  • 22.4 Concurrent collections
  • 22.4.1 ConcurrentDictionary TKey TValue
  • 22.4.2 ConcurrentQueue T
  • 22.4.3 ConcurrentStack T
  • 22.4.4 ConcurrentBag T
  • 22.4.5 BlockingCollection T
  • 22.4.6 Channel T producer consumer async support
  • 22.5 Project Thread Safe Counter with Interlocked
• Chapter 23 : Advanced Testing and Debugging Techniques

  • 23.1 Snapshot testing with Verify
  • 23.1.1 Serialising expected output
  • 23.1.2 Diffing changes
  • 23.2 Fuzzing random inputs
  • 23.2.1 FsCheck for property based testing
  • 23.2.2 Generating arbitrary values
  • 23.2.3 Shrinking counterexamples
  • 23.3 Debugging with WinDbg SOS
  • 23.3.1 Attaching to a process
  • 23.3.2 dumpheap and gcroot commands
  • 23.3.3 Analysing deadlocks high CPU
  • 23.4 Chaos engineering
  • 23.4.1 Simulating failures with Polly chaos policies
  • 23.4.2 Fault injection in integration tests
  • 23.5 Project Property Based Test for Sort Algorithm
• Chapter 24 : REST API Deep Dive

  • 24.1 Controllers vs minimal APIs
  • 24.1.1 Controller based ApiController Route
  • 24.1.2 Minimal APIs MapGet MapPost
  • 24.1.3 Trade offs simplicity vs features
  • 24.2 Routing and model binding
  • 24.2.1 Attribute routing
  • 24.2.2 Route constraints
  • 24.2.3 From body query route header
  • 24.3 Validation
  • 24.3.1 Data annotations Required MaxLength
  • 24.3.2 ApiController automatic validation
  • 24.3.3 Custom validation attributes
  • 24.3.4 FluentValidation external library
  • 24.4 Content negotiation
  • 24.4.1 Accept header
  • 24.4.2 Produces and Consumes attributes
  • 24.4.3 Custom formatters
  • 24.5 API versioning
  • 24.5.1 URL path versioning
  • 24.5.2 Query string versioning
  • 24.5.3 Header versioning
  • 24.5.4 Microsoft.AspNetCore.Mvc.Versioning
  • 24.6 OpenAPI and Swagger
  • 24.6.1 Swashbuckle.AspNetCore
  • 24.6.2 Generating Swagger JSON
  • 24.6.3 Swagger UI for testing
  • 24.6.4 Annotations ProducesResponseType
  • 24.7 Problem Details RFC 7807
  • 24.7.1 ProblemDetails class
  • 24.7.2 ValidationProblemDetails for errors
  • 24.7.3 Results.Problem in minimal APIs
  • 24.8 Project Todo API with Versioning and OpenAPI
• Chapter 25 : API Security Deep Dive

  • 25.1 CORS
  • 25.1.1 Same origin policy
  • 25.1.2 Preflight requests OPTIONS
  • 25.1.3 AddCors and UseCors
  • 25.1.4 Allowed origins methods headers
  • 25.1.5 Credentials AllowCredentials
  • 25.2 Rate limiting
  • 25.2.1 Fixed window sliding window token bucket concurrency
  • 25.2.2 Built in .Net 7 and later AddRateLimiter EnableRateLimiting
  • 25.2.3 Partitioning by user IP API key
  • 25.2.4 Returning 429 with Retry After
  • 25.3 Security headers
  • 25.3.1 HSTS Strict Transport Security
  • 25.3.2 CSP Content Security Policy
  • 25.3.3 X Frame Options clickjacking
  • 25.3.4 X Content Type Options nosniff
  • 25.3.5 Referrer Policy
  • 25.4 API keys
  • 25.4.1 Header or query string
  • 25.4.2 Custom authentication handler
  • 25.4.3 Storing keys securely Azure Key Vault Data Protection
  • 25.5 HMAC signing
  • 25.5.1 Request signing client computes hash
  • 25.5.2 Server recomputes and compares
  • 25.5.3 Replay attack prevention nonce timestamp
  • 25.6 Data Protection DPAPI
  • 25.6.1 IDataProtectionProvider
  • 25.6.2 Protect and Unprotect
  • 25.6.3 Key ring storage automatic rotation
  • 25.6.4 Purpose strings isolated keys
  • 25.7 Input validation
  • 25.7.1 Built in anti XSS not enough
  • 25.7.2 FluentValidation for complex rules
  • 25.7.3 Whitelisting vs blacklisting
  • 25.8 OWASP Top 10 for APIs
  • 25.8.1 API1 Broken object level authorisation
  • 25.8.2 API2 Broken authentication
  • 25.8.3 API3 Excessive data exposure
  • 25.8.4 API4 Lack of rate limiting
  • 25.8.5 API5 Broken function level authorisation
  • 25.8.6 API6 Mass assignment
  • 25.8.7 API7 Security misconfiguration
  • 25.8.8 API8 Injection
  • 25.8.9 API9 Improper asset management
  • 25.8.10 API10 Insufficient logging and monitoring
  • 25.9 Project Secured Weather API
• Chapter 26 : Authentication in ASP.NET Core

  • 26.1 Authentication schemes
  • 26.1.1 Cookie authentication for traditional web apps
  • 26.1.2 JWT Bearer for API tokens
  • 26.1.3 OAuth 2.0 and OpenID Connect external providers
  • 26.2 Setup
  • 26.2.1 AddAuthentication and AddJwtBearer
  • 26.2.2 Authorize attribute
  • 26.2.3 AuthenticationHandler custom logic
  • 26.3 JWT details
  • 26.3.1 Header payload signature
  • 26.3.2 Issuer audience expiration
  • 26.3.3 Symmetric HMAC vs asymmetric RSA signing
  • 26.4 Project JWT Authentication for Todo API
• Chapter 27 : Authorization Role Policy and Resource Based

  • 27.1 Role based
  • 27.1.1 Authorize with Roles
  • 27.1.2 Claims with role type
  • 27.2 Policy based
  • 27.2.1 AddAuthorization with policies
  • 27.2.2 RequireClaim RequireRole RequireAssertion
  • 27.2.3 Custom IAuthorizationRequirement and AuthorizationHandler
  • 27.3 Resource based
  • 27.3.1 Inject IAuthorizationService
  • 27.3.2 Call AuthorizeAsync with user resource requirement
  • 27.3.3 Inside endpoint check ownership
  • 27.4 Project Todo API with Role and Ownership Policies
• Chapter 28 : Database Access with EF Core and Dapper

  • 28.1 EF Core
  • 28.1.1 DbContext DbSet
  • 28.1.2 Migrations Add Migration Update Database
  • 28.1.3 LINQ queries translated to SQL
  • 28.1.4 Change tracking and SaveChanges
  • 28.1.5 Concurrency tokens Timestamp
  • 28.2 Dapper
  • 28.2.1 QueryAsync T raw SQL
  • 28.2.2 ExecuteAsync non query
  • 28.2.3 Multi mapping QueryAsync T U TResult
  • 28.2.4 Performance advantage over EF Core
  • 28.3 When to use which
  • 28.3.1 EF Core for complex object graphs migrations
  • 28.3.2 Dapper for read only high performance queries
  • 28.3.3 Using both together CQRS lite
  • 28.4 Project Blogging API with EF Core for writes and Dapper for reads
• Chapter 29 : File IO and Streams for Backend Developers

  • 29.1 File system helpers
  • 29.1.1 File Directory FileInfo DirectoryInfo
  • 29.1.2 ReadAllText WriteAllText convenience but loads entire file
  • 29.2 Streams
  • 29.2.1 FileStream read write bytes
  • 29.2.2 StreamReader StreamWriter for text
  • 29.2.3 MemoryStream in memory buffer
  • 29.2.4 GZipStream compression
  • 29.3 Streaming responses
  • 29.3.1 Results.Stream in minimal API
  • 29.3.2 FileStreamResult in controller
  • 29.3.3 Avoid loading large files into memory
  • 29.4 Project File Upload and Download API
• Chapter 30 : Message Queues and Event Driven Architecture

  • 30.1 Message brokers
  • 30.1.1 RabbitMQ popular AMQP
  • 30.1.2 Azure Service Bus cloud
  • 30.1.3 AWS SQS SNS
  • 30.1.4 Kafka high throughput
  • 30.2 Abstractions
  • 30.2.1 MassTransit supports multiple brokers
  • 30.2.2 NServiceBus commercial
  • 30.2.3 Raw client libraries
  • 30.3 Idempotency
  • 30.3.1 Idempotency keys in message headers
  • 30.3.2 Storing processed message IDs
  • 30.3.3 Exactly once delivery not truly possible but idempotent consumers
  • 30.4 Outbox pattern
  • 30.4.1 Store messages in database as part of transaction
  • 30.4.2 Background processor publishes to broker
  • 30.4.3 Prevents lost messages on broker failure
  • 30.5 Dead letter queues
  • 30.5.1 Handling poison messages
  • 30.5.2 Retry policies and dead letter after max attempts
  • 30.6 Project Order Processing with RabbitMQ and MassTransit
• Chapter 31 : gRPC for High Performance APIs

  • 31.1 Protocol Buffers
  • 31.1.1 proto syntax for messages and services
  • 31.1.2 Scalar types int32 string bool
  • 31.1.3 Repeated fields enums nested messages
  • 31.2 gRPC service types
  • 31.2.1 Unary request response
  • 31.2.2 Server streaming many responses
  • 31.2.3 Client streaming many requests
  • 31.2.4 Bidirectional streaming
  • 31.3 Implementation in .Net
  • 31.3.1 Grpc.AspNetCore package
  • 31.3.2 Code generation from proto
  • 31.3.3 Service implementation inherits generated base
  • 31.4 gRPC vs REST
  • 31.4.1 Performance binary HTTP2 multiplexing
  • 31.4.2 Contract first vs code first
  • 31.4.3 gRPC Web for browser clients
  • 31.5 Project Stock Price Streaming Service
• Chapter 32 : Real Time Communication with SignalR

  • 32.1 Hubs
  • 32.1.1 Hub class
  • 32.1.2 Methods callable from client
  • 32.1.3 Calling client methods
  • 32.2 Connection management
  • 32.2.1 OnConnectedAsync and OnDisconnectedAsync
  • 32.2.2 Keeping connection IDs
  • 32.2.3 Reconnection logic
  • 32.3 Scaling out
  • 32.3.1 Redis backplane
  • 32.3.2 Azure SignalR Service fully managed
  • 32.3.3 Sticky sessions if not using backplane
  • 32.4 Transports
  • 32.4.1 WebSockets best performance
  • 32.4.2 Server Sent Events SSE
  • 32.4.3 Long polling fallback
  • 32.5 Project Live Chat Application
• Chapter 33 : Docker and Containerisation for .Net Backend

  • 33.1 Docker basics
  • 33.1.1 Dockerfile FROM WORKDIR COPY RUN EXPOSE ENTRYPOINT
  • 33.1.2 Multi stage builds build vs runtime images
  • 33.1.3 dockerignore
  • 33.2 Docker Compose
  • 33.2.1 docker-compose.yml services .Networks volumes
  • 33.2.2 Environment variables
  • 33.2.3 Dependencies depends on
  • 33.3 Health checks
  • 33.3.1 HEALTHCHECK in Dockerfile
  • 33.3.2 ASP.NET Core health checks AddHealthChecks
  • 33.4 Project Dockerise the Todo API with PostgreSQL
• Chapter 34 : CI CD for .Net Backend

  • 34.1 CI CD platforms
  • 34.1.1 GitHub Actions
  • 34.1.2 Azure DevOps Pipelines
  • 34.1.3 GitLab CI
  • 34.1.4 Jenkins legacy
  • 34.2 Typical pipeline
  • 34.2.1 Build dotnet build
  • 34.2.2 Test dotnet test
  • 34.2.3 Publish dotnet publish
  • 34.2.4 Build Docker image docker build
  • 34.2.5 Push to registry docker push
  • 34.2.6 Deploy to Azure Container Instances Kubernetes VM
  • 34.3 Infrastructure as Code
  • 34.3.1 Bicep for Azure Resource Manager
  • 34.3.2 Terraform multi cloud
  • 34.4 Project GitHub Actions CI CD for Todo API
• Chapter 35 : Mid Point Capstone Secure Role Based Access plus OTP REST API

  • 35.1 Project overview
  • 35.2 Features JWT roles OTP rate limiting idempotency
  • 35.3 Implementation steps
  • 35.3.1 Scaffold ASP.NET Core project with JWT
  • 35.3.2 Implement user registration and login
  • 35.3.3 Add role claims and admin endpoints
  • 35.3.4 OTP generation service 6 digits with expiry
  • 35.3.5 Background service plus channel for email sending
  • 35.3.6 Idempotency middleware with Redis
  • 35.3.7 Integration tests
  • 35.3.8 Docker and CI CD
  • 35.4 Deliverables
• Chapter 36 : Beyond Senior Distributed Systems Cloud Native and Leadership

  • 36.1 Microservices vs modular monolith
  • 36.1.1 Benefits and trade offs
  • 36.1.2 Service discovery Consul Eureka
  • 36.1.3 API gateways Ocelot YARP Kong
  • 36.2 Distributed transactions
  • 36.2.1 Two phase commit not common in microservices
  • 36.2.2 Saga pattern choreography vs orchestration
  • 36.2.3 Idempotency and compensating transactions
  • 36.3 Cloud native patterns
  • 36.3.1 Retry and circuit breaker with Polly
  • 36.3.2 Sidecar pattern for example Dapr
  • 36.3.3 Health checks and liveness probes
  • 36.4 Leadership
  • 36.4.1 Architecture Decision Records ADR
  • 36.4.2 Running technical design reviews
  • 36.4.3 Mentoring senior engineers
  • 36.5 Project ADR and Proof of Concept for Saga Pattern
• Chapter 37 : Final Mastery Project Banking Core System for Finance

  • 37.1 Business context
  • 37.2 Core features accounts transfers interest real time feed
  • 37.3 Technical challenges idempotency concurrency outbox tracing
  • 37.4 Solution structure modular monolith
  • 37.5 Data models
  • 37.6 Implementation steps
  • 37.6.1 Create solution with four projects
  • 37.6.2 Define domain models and DbContext
  • 37.6.3 Implement idempotent transfer endpoint
  • 37.6.4 Add optimistic concurrency row version
  • 37.6.5 Set up RabbitMQ and MassTransit
  • 37.6.6 Implement SignalR hub for balance updates
  • 37.6.7 Background workers scheduled payments interest outbox
  • 37.6.8 Add Polly retries for notifications
  • 37.6.9 Configure OpenTelemetry and Jaeger
  • 37.6.10 Write Docker Compose
  • 37.6.11 Write k6 load test
  • 37.6.12 Set up CI CD
  • 37.7 Deliverables
  • 37.8 Optional extensions