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+# AppKit – Go Application Framework Utilities
+
+[![Linter Status](https://github.com/vmkteam/appkit/actions/workflows/golangci-lint.yml/badge.svg?branch=master)](https://github.com/vmkteam/appkit/actions)
+[![Go Report Card](https://goreportcard.com/badge/github.com/vmkteam/appkit)](https://goreportcard.com/report/github.com/vmkteam/appkit)
+[![Go Reference](https://pkg.go.dev/badge/github.com/vmkteam/appkit.svg)](https://pkg.go.dev/github.com/vmkteam/appkit)
+
+A comprehensive Go utility package providing common application framework components for building production-ready HTTP services.
+
+## Features
+
+### Core Utilities
+- **Version Management**: Automatically extracts version information from VCS (Git) build info
+- **HTTP Headers**: Pre-configured internal service headers with app name and version
+
+### Echo Framework Integration
+- **Pre-configured Echo Server**: Ready-to-use Echo instance with security and monitoring middleware
+- **IP Extraction**: Proper IP handling with real IP header support and CIDR trust ranges
+- **Sentry Integration**: Built-in error tracking with Sentry middleware
+- **Route Rendering**: Automatic HTML route listing for service discovery
+
+### Monitoring & Metrics
+- **Prometheus Integration**: Comprehensive HTTP metrics (request count, response duration)
+- **Metadata Management**: Service configuration tracking and metrics registration
+- **pprof Support**: Built-in profiling endpoint handler
+
+### Service Metadata
+- **Service Discovery**: Track internal and external service dependencies
+- **Database Monitoring**: Connection tracking and replica status
+- **API Exposure**: Public/private API configuration tracking
+
+## Usage Examples
+
+Please see example/main.go
+
+### Basic HTTP Server with Metrics
+
+```go
+e := appkit.NewEcho()
+
+// Add Prometheus metrics
+e.Use(appkit.HTTPMetrics("api-service"))
+
+// Route rendering for service discovery
+e.GET("/", appkit.RenderRoutes("API Service", e))
+
+// pprof endpoints
+e.GET("/debug/pprof/*", appkit.PprofHandler)
+```
+
+### Service Metadata Configuration
+
+```go
+metadata := appkit.NewMetadataManager(appkit.MetadataOpts{
+    DBs: []appkit.DBMetadata{
+        appkit.NewDBMetadata("postgres", 10, false),
+        appkit.NewDBMetadata("redis", 5, true),
+    },
+    HasPublicAPI:      true,
+    HasPrivateAPI:     false,
+    HasBrokersrvQueue: true,
+    HasCronJobs:       true,
+    Services: []appkit.ServiceMetadata{
+        appkit.NewServiceMetadata("auth-service", appkit.MetadataServiceTypeSync),
+        appkit.NewServiceMetadata("payment-service", appkit.MetadataServiceTypeExternal),
+    },
+})
+
+// Register metrics
+metadata.RegisterMetrics()
+
+// Add metadata endpoint
+e.GET("/metadata", metadata.Handler)
+```
+
+### Internal Service Communication
+
+```go
+func callInternalService() {
+    headers := appkit.NewInternalHeaders("worker-service", appkit.Version())
+
+    req, _ := http.NewRequest("GET", "http://api-service/internal/data", nil)
+    req.Header = headers
+
+    // Make request with proper internal headers
+    client.Do(req)
+}
+```
+
+## API Reference
+
+### Core Functions
+
+- `Version() string` - Returns VCS revision or "devel"
+- `NewInternalHeaders(appName, version string) http.Header` - Creates standardized internal headers
+
+### Echo Framework
+
+- `NewEcho() *echo.Echo` - Creates pre-configured Echo instance
+- `RenderRoutes(appName string, e *echo.Echo) echo.HandlerFunc` - HTML route renderer
+- `PprofHandler(c echo.Context) error` - pprof endpoint handler
+- `EchoHandlerFunc(next http.HandlerFunc) echo.HandlerFunc` - HTTP handler wrapper
+
+### Metrics & Monitoring
+
+- `HTTPMetrics(serverName string) echo.MiddlewareFunc` - Prometheus HTTP metrics middleware
+- `MetadataManager` - Service metadata configuration and metrics
+
+## Dependencies
+
+- [Echo](https://echo.labstack.com/) - High performance HTTP framework
+- [Prometheus](https://prometheus.io/) - Metrics collection and monitoring
+- [Sentry](https://sentry.io/) - Error tracking and monitoring
+- [zenrpc-middleware](https://github.com/vmkteam/zenrpc-middleware) - RPC middleware utilities
+
+## Metrics Exported
+
+### HTTP Metrics
+- `app_http_requests_total` - Total HTTP requests by method/path/status
+- `app_http_responses_duration_seconds` - Response time distribution
+
+### Service Metadata Metrics
+- `app_metadata_service` - Service configuration information
+- `app_metadata_db_connections_total` - Database connection counts
+- `app_metadata_services` - Service dependencies
+
+## License
+
+MIT License - see LICENSE file for details.