Backend Architecture

The Ryva backend is a high-performance Go API built with clean architecture principles, following the handler → service → repository pattern for maintainable and testable code.

Technology Stack

Language & Router

Go 1.25 - Latest Go features
Chi v5 - Lightweight, composable router
CORS - Chi CORS middleware

Database

PostgreSQL - Primary database
pgx/v5 - High-performance PostgreSQL driver
Connection pooling - pgxpool
Migrations - SQL migration files

External Services

Supabase - Authentication (JWT validation)
Stripe - Payment processing
Resend - Transactional emails
Sentry - Error tracking

Development

Air - Hot reload for Go
godotenv - Environment variables
testify - Testing framework
golangci-lint - Code linting

Project Structure

apps/api/
├── cmd/
│   └── server/
│       └── main.go              # Application entry point
├── internal/                    # Private application code
│   ├── modules/                # Feature modules
│   │   ├── auth/              # Authentication module
│   │   │   ├── handler.go     # HTTP handlers
│   │   │   ├── service.go     # Business logic
│   │   │   ├── repository.go  # Data access
│   │   │   ├── models.go      # Domain models
│   │   │   └── dto.go         # Data transfer objects
│   │   ├── organizations/     # Organization management
│   │   ├── billing/           # Stripe integration
│   │   ├── waitlist/          # Waitlist management
│   │   └── stripe/            # Stripe webhook handling
│   ├── router/                # HTTP routing
│   │   ├── router.go          # Router setup
│   │   └── routes.go          # Route definitions
│   ├── shared/                # Shared utilities
│   │   ├── middleware/        # HTTP middleware
│   │   ├── database/          # Database utilities
│   │   ├── email/             # Email service
│   │   ├── apperrors/         # Error types
│   │   ├── httputil/          # HTTP helpers
│   │   └── logger/            # Logging utilities
│   ├── config/                # Configuration
│   └── db/                    # Generated database code (sqlc)
│       ├── auth/              # Auth queries
│       ├── organizations/     # Organization queries
│       └── billing/           # Billing queries
├── db/                         # Database files
│   ├── migrations/            # SQL migrations
│   │   ├── 001_initial.up.sql
│   │   └── 001_initial.down.sql
│   └── queries/               # SQL query definitions (sqlc)
│       ├── auth.sql
│       ├── organizations.sql
│       └── billing.sql
├── Dockerfile                  # Multi-stage Docker build
├── Makefile                    # Build automation
├── go.mod                      # Go module definition
└── .air.toml                   # Air hot reload config

Clean Architecture Pattern

Ryva follows a three-layer architecture: Handler → Service → Repository. Each layer has a specific responsibility and depends only on layers below it.

Architecture Layers

┌─────────────────────────────────────────┐
│            Handler Layer                │
│  • HTTP request/response handling       │
│  • Input validation (DTO)               │
│  • Auth context extraction              │
│  • Response formatting (JSON)           │
└───────────────┬─────────────────────────┘
                │
                ▼
┌─────────────────────────────────────────┐
│            Service Layer                │
│  • Business logic                       │
│  • Input validation (domain rules)      │
│  • Error handling                       │
│  • Transaction coordination             │
└───────────────┬─────────────────────────┘
                │
                ▼
┌─────────────────────────────────────────┐
│          Repository Layer               │
│  • Database queries                     │
│  • Data mapping (DB ↔ Domain)          │
│  • Connection management                │
│  • Query composition                    │
└─────────────────────────────────────────┘

Layer Responsibilities

Handler Layer

Responsibilities:

Parse HTTP requests
Validate request DTOs
Extract authentication context
Call service methods
Format responses as JSON
Handle HTTP errors

Example (apps/api/internal/modules/auth/handler.go:1-175):

func (h *Handler) GetMe(w http.ResponseWriter, r *http.Request) {
    userID := middleware.GetUserID(r.Context())
    
    user, err := h.service.GetMe(r.Context(), userID)
    if err != nil {
        httputil.Error(w, r, err)
        return
    }
    
    httputil.Success(w, r, user)
}

Service Layer

Responsibilities:

Implement business logic
Validate domain rules
Coordinate multiple repositories
Handle transactions
Return domain errors

Example (apps/api/internal/modules/auth/service.go:24-31):

func (s *Service) GetMe(ctx context.Context, userID uuid.UUID) (*User, error) {
    user, err := s.repo.GetUserByID(ctx, userID)
    if err != nil {
        return nil, err
    }
    return user, nil
}

Repository Layer

Responsibilities:

Execute database queries
Map database rows to domain models
Handle database errors
Use prepared statements

Example (apps/api/internal/modules/auth/repository.go:1-149):

func (r *Repository) GetUserByID(ctx context.Context, id uuid.UUID) (*User, error) {
    row := r.queries.GetUserByID(ctx, id)
    if err := row.Scan(&user); err != nil {
        if errors.Is(err, pgx.ErrNoRows) {
            return nil, apperrors.NotFound("user not found")
        }
        return nil, err
    }
    return &user, nil
}

Module Architecture

Each feature module follows a consistent structure:

internal/modules/auth/
├── handler.go      # HTTP handlers
├── service.go      # Business logic
├── repository.go   # Data access
├── models.go       # Domain models
├── dto.go          # Request/response DTOs
├── *_test.go       # Unit tests
└── README.md       # Module documentation

Example: Auth Module

handler.go

HTTP request handlers:

GetMe - Get current user
UpdateProfile - Update user profile
CompleteOnboarding - Mark onboarding complete
GetPreferences - Get user preferences
UpdatePreferences - Update preferences

service.go

Business logic:

Input validation
Business rule enforcement
Error handling
Coordination between repos

repository.go

Database operations:

GetUserByID
UpdateUserProfile
CompleteOnboarding
GetUserPreferences
UpdateUserPreferences

models.go

Domain models:

User - User entity
UserWithOrganizations
Helper methods
Validation logic

Creating a New Module

Create module directory:
```
mkdir -p internal/modules/myfeature
```

Create handler.go:

package myfeature

type Handler struct {
    service *Service
}

func NewHandler(service *Service) *Handler {
    return &Handler{service: service}
}

func (h *Handler) HandleRequest(w http.ResponseWriter, r *http.Request) {
    // Handler implementation
}

Create service.go:

package myfeature

type Service struct {
    repo RepositoryInterface
}

func NewService(repo RepositoryInterface) *Service {
    return &Service{repo: repo}
}

func (s *Service) DoSomething(ctx context.Context) error {
    // Business logic
    return nil
}

Create repository.go:

package myfeature

type Repository struct {
    db *pgxpool.Pool
}

func NewRepository(db *pgxpool.Pool) *Repository {
    return &Repository{db: db}
}

func (r *Repository) GetData(ctx context.Context) error {
    // Database query
    return nil
}

Register routes in router:

r.Route("/v1/myfeature", func(r chi.Router) {
    r.Use(authMiddleware)
    r.Get("/", handlers.MyFeature.HandleRequest)
})

Router Architecture

The router (apps/api/internal/router/router.go:1-123) uses Chi for composable routing:

Middleware Stack

func ApplyStandardMiddleware(r *chi.Mux, config Config) {
    r.Use(middleware.RequestID)        // Add request ID
    r.Use(middleware.RealIP)           // Get real IP
    r.Use(middleware.Logger)           // Log requests
    r.Use(middleware.Recoverer)        // Recover from panics
    r.Use(middleware.CORS)             // CORS headers
    r.Use(middleware.Timeout(30s))     // Request timeout
}

Route Organization

func registerAPIRoutes(r *chi.Mux, authConfig AuthMiddleware, handlers Handlers) {
    authMiddleware := getAuthMiddleware(authConfig)
    
    r.Route("/v1", func(r chi.Router) {
        // Public routes
        r.Post("/waitlist", handlers.Waitlist.Join)
        
        // Protected routes
        r.Route("/auth", func(r chi.Router) {
            r.Use(authMiddleware)
            r.Get("/me", handlers.Auth.GetMe)
            r.Patch("/profile", handlers.Auth.UpdateProfile)
        })
        
        r.Route("/organizations", func(r chi.Router) {
            r.Use(authMiddleware)
            r.Post("/", handlers.Organizations.CreateOrganization)
            r.Get("/", handlers.Organizations.ListUserOrganizations)
        })
    })
}

Authentication & Authorization

JWT Validation Middleware

The auth middleware validates JWT tokens from Supabase:

func RequireAuth(config AuthConfig) func(http.Handler) http.Handler {
    return func(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
            // Extract token from Authorization header
            token := extractToken(r)
            
            // Validate JWT with Supabase
            claims, err := validateJWT(token, config)
            if err != nil {
                httputil.Unauthorized(w, r, "invalid token")
                return
            }
            
            // Add user ID to context
            ctx := context.WithValue(r.Context(), "user_id", claims.UserID)
            next.ServeHTTP(w, r.WithContext(ctx))
        })
    }
}

Extracting User ID

func GetUserID(ctx context.Context) uuid.UUID {
    userID, ok := ctx.Value("user_id").(uuid.UUID)
    if !ok {
        panic("user_id not found in context")
    }
    return userID
}

Error Handling

Error Types

Ryva defines custom error types in internal/shared/apperrors/:

package apperrors

type AppError struct {
    Code    string
    Message string
    Status  int
}

func (e *AppError) Error() string {
    return e.Message
}

// Error constructors
func NotFound(message string) *AppError {
    return &AppError{
        Code:    "NOT_FOUND",
        Message: message,
        Status:  http.StatusNotFound,
    }
}

func InvalidInput(message string) *AppError {
    return &AppError{
        Code:    "INVALID_INPUT",
        Message: message,
        Status:  http.StatusBadRequest,
    }
}

func Unauthorized(message string) *AppError {
    return &AppError{
        Code:    "UNAUTHORIZED",
        Message: message,
        Status:  http.StatusUnauthorized,
    }
}

func BusinessRuleViolation(message string) *AppError {
    return &AppError{
        Code:    "BUSINESS_RULE_VIOLATION",
        Message: message,
        Status:  http.StatusBadRequest,
    }
}

Error Response Format

func Error(w http.ResponseWriter, r *http.Request, err error) {
    var appErr *AppError
    if errors.As(err, &appErr) {
        w.WriteHeader(appErr.Status)
        json.NewEncoder(w).Encode(map[string]any{
            "success": false,
            "error": map[string]any{
                "code":    appErr.Code,
                "message": appErr.Message,
            },
        })
        return
    }
    
    // Unknown error - return 500
    w.WriteHeader(http.StatusInternalServerError)
    json.NewEncoder(w).Encode(map[string]any{
        "success": false,
        "error": map[string]any{
            "code":    "INTERNAL_ERROR",
            "message": "An internal error occurred",
        },
    })
}

Error Handling Best Practices

Never Ignore Errors

// Bad
user, _ := s.repo.GetUserByID(ctx, userID)

// Good
user, err := s.repo.GetUserByID(ctx, userID)
if err != nil {
    return nil, err
}

Wrap Errors with Context

user, err := s.repo.GetUserByID(ctx, userID)
if err != nil {
    return nil, fmt.Errorf("failed to get user: %w", err)
}

Use Custom Error Types

if user == nil {
    return apperrors.NotFound("user not found")
}

if email == "" {
    return apperrors.InvalidInput("email is required")
}

Database Architecture

Connection Pooling

Ryva uses pgxpool for efficient connection management:

func NewPool(ctx context.Context, config Config) (*pgxpool.Pool, error) {
    poolConfig, err := pgxpool.ParseConfig(getDatabaseURL())
    if err != nil {
        return nil, err
    }
    
    // Configure pool
    poolConfig.MaxConns = 25
    poolConfig.MinConns = 5
    poolConfig.MaxConnLifetime = time.Hour
    poolConfig.MaxConnIdleTime = 30 * time.Minute
    
    // Disable prepared statements in development
    if config.IsDevelopment {
        poolConfig.ConnConfig.DefaultQueryExecMode = pgx.QueryExecModeSimpleProtocol
    }
    
    pool, err := pgxpool.NewWithConfig(ctx, poolConfig)
    if err != nil {
        return nil, err
    }
    
    // Test connection
    if err := pool.Ping(ctx); err != nil {
        return nil, err
    }
    
    return pool, nil
}

Migrations

Migrations are SQL files in db/migrations/:

-- 001_initial.up.sql
CREATE TABLE users (
    id UUID PRIMARY KEY,
    email TEXT NOT NULL UNIQUE,
    full_name TEXT,
    avatar_url TEXT,
    onboarding_completed BOOLEAN DEFAULT FALSE,
    preferences JSONB DEFAULT '{}',
    created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
    updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

CREATE INDEX idx_users_email ON users(email);

-- 001_initial.down.sql
DROP TABLE IF EXISTS users;

Query Generation with sqlc

Queries are defined in db/queries/ and generated into type-safe Go code:

-- db/queries/auth.sql
-- name: GetUserByID :one
SELECT * FROM users WHERE id = $1;

-- name: UpdateUserProfile :one
UPDATE users
SET full_name = COALESCE($2, full_name),
    avatar_url = COALESCE($3, avatar_url),
    updated_at = NOW()
WHERE id = $1
RETURNING *;

Generated code (internal/db/auth/):

func (q *Queries) GetUserByID(ctx context.Context, id uuid.UUID) (User, error) {
    // Generated implementation
}

func (q *Queries) UpdateUserProfile(ctx context.Context, arg UpdateUserProfileParams) (User, error) {
    // Generated implementation
}

Application Initialization

The main.go file (apps/api/cmd/server/main.go:34-217) orchestrates service initialization:

func main() {
    // 1. Load environment variables
    godotenv.Load()
    
    // 2. Initialize Sentry
    sentry.Init(sentry.ClientOptions{
        Dsn: os.Getenv("SENTRY_DSN"),
    })
    
    // 3. Connect to database
    dbPool, err := database.NewPool(ctx, database.Config{
        IsDevelopment: getEnvironment() == "development",
    })
    
    // 4. Initialize email service
    emailClient := email.NewClient(email.Config{...})
    
    // 5. Initialize modules
    waitlistRepo := waitlist.NewRepository(dbPool)
    waitlistService := waitlist.NewService(waitlistRepo, emailClient)
    waitlistHandler := waitlist.NewHandler(waitlistService)
    
    authRepo := auth.NewRepository(dbPool)
    authService := auth.NewService(authRepo)
    authHandler := auth.NewHandler(authService)
    
    // 6. Create router
    r := router.New(middlewareConfig, authConfig, router.Handlers{
        Waitlist: waitlistHandler,
        Auth: authHandler,
    })
    
    // 7. Start server
    server := &http.Server{
        Addr:    ":8080",
        Handler: r,
    }
    server.ListenAndServe()
}

Testing Strategy

Unit Tests

// auth/service_test.go
func TestGetMe(t *testing.T) {
    mockRepo := &MockRepository{}
    service := NewService(mockRepo)
    
    userID := uuid.New()
    expectedUser := &User{
        ID:    userID,
        Email: "test@example.com",
    }
    
    mockRepo.On("GetUserByID", mock.Anything, userID).Return(expectedUser, nil)
    
    user, err := service.GetMe(context.Background(), userID)
    
    assert.NoError(t, err)
    assert.Equal(t, expectedUser, user)
}

Integration Tests

func TestCreateOrganization(t *testing.T) {
    // Setup test database
    pool := setupTestDB(t)
    defer pool.Close()
    
    repo := NewRepository(pool)
    service := NewService(repo)
    
    // Test organization creation
    org, err := service.CreateOrganization(ctx, CreateOrgRequest{
        Name: "Test Org",
    })
    
    assert.NoError(t, err)
    assert.NotNil(t, org)
    assert.Equal(t, "Test Org", org.Name)
}

Best Practices

Error Handling

Never ignore errors
Always return and wrap errors
Use custom error types for business logic errors
Log errors with context

Context Usage

Always pass context.Context as the first parameter
Use context for cancellation and timeouts
Store request-scoped data in context (user ID, request ID)
Never store context in a struct

Input Validation

Validate all inputs at the handler level (DTOs)
Validate business rules at the service level
Return descriptive error messages
Use InvalidInput errors for validation failures

Database Operations

Use connection pooling (pgxpool)
Always use prepared statements in production
Use transactions for multi-step operations
Handle pgx.ErrNoRows explicitly

Code Organization

Keep handlers thin (just HTTP concerns)
Put business logic in services
Keep repositories focused on data access
Use interfaces for testability

Development Workflow

Local Development with Air

cd apps/api
make dev          # Starts Air hot reload

Air watches for file changes and automatically rebuilds and restarts the server.

Common Commands

make build        # Build binary
make test         # Run tests
make lint         # Run golangci-lint
make format       # Format code with gofmt

Docker Build

The Dockerfile (apps/api/Dockerfile:1-50) uses multi-stage builds:

# Build stage
FROM golang:1.25-alpine AS builder
WORKDIR /app
COPY go.mod go.sum ./
RUN go mod download
COPY . .
RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o api ./cmd/server/main.go

# Runtime stage
FROM alpine:3.20
RUN apk add --no-cache ca-certificates curl
RUN adduser -D -s /bin/sh appuser
USER appuser
WORKDIR /app
COPY --from=builder /app/api .
HEALTHCHECK --interval=30s --timeout=5s CMD curl -f http://localhost:8080/health || exit 1
CMD ["./api"]

Benefits:

Small final image (~20MB)
Security (runs as non-root user)
Health checks built-in
Fast builds with layer caching

Next Steps

Frontend Architecture

Learn about Next.js structure and state management

Infrastructure

Understand Docker, Caddy, and deployment setup

Documentation Index

​Backend Architecture

​Technology Stack

Language & Router

Database

External Services

Development

​Project Structure

​Clean Architecture Pattern

​Architecture Layers

​Layer Responsibilities

​Module Architecture

​Example: Auth Module

handler.go

service.go

repository.go

models.go

​Creating a New Module

​Router Architecture

​Middleware Stack

​Route Organization

​Authentication & Authorization

​JWT Validation Middleware

​Extracting User ID

​Error Handling

​Error Types

​Error Response Format

​Error Handling Best Practices

​Database Architecture

​Connection Pooling

​Migrations

​Query Generation with sqlc

​Application Initialization

​Testing Strategy

​Unit Tests

​Integration Tests

​Best Practices

​Development Workflow

​Local Development with Air

​Common Commands

​Docker Build

​Next Steps

Frontend Architecture

Infrastructure

Backend Architecture

Technology Stack

Project Structure

Clean Architecture Pattern

Architecture Layers

Layer Responsibilities

Module Architecture

Example: Auth Module

Creating a New Module

Router Architecture

Middleware Stack

Route Organization

Authentication & Authorization

JWT Validation Middleware

Extracting User ID

Error Handling

Error Types

Error Response Format

Error Handling Best Practices

Database Architecture

Connection Pooling

Migrations

Query Generation with sqlc

Application Initialization

Testing Strategy

Unit Tests

Integration Tests

Best Practices

Development Workflow

Local Development with Air

Common Commands

Docker Build

Next Steps