📚 surf - Awesome Go Library for Networking

Advanced HTTP client with HTTP/1.1, HTTP/2, HTTP/3 (QUIC), SOCKS5 proxy support and browser-grade TLS fingerprinting
Detailed Description of surf
Surf - Advanced HTTP Client for Go
Surf is a powerful, feature-rich HTTP client library for Go that makes working with HTTP requests intuitive and enjoyable. With advanced features like browser impersonation, JA3/JA4 fingerprinting, and comprehensive middleware support, Surf provides everything you need for modern web interactions.
✨ Key Features
🎭 Browser Impersonation
- Chrome & Firefox Support: Accurately mimic Chrome v145 and Firefox v148 browser fingerprints
- Platform Diversity: Impersonate Windows, macOS, Linux, Android, and iOS devices
- TLS Fingerprinting: Full JA3/JA4 fingerprint customization for enhanced privacy
- Automatic Headers: Proper header ordering and browser-specific values
- WebKit Form Boundaries: Accurate multipart form boundary generation matching real browsers
🔒 Advanced TLS & Security
- Custom JA3/JA4: Configure precise TLS fingerprints with
HelloIDandHelloSpec - HTTP/3 Support: Full HTTP/3 over QUIC with complete browser-specific fingerprinting
- HTTP/2 & HTTP/3: Full HTTP/2 support with customizable settings (SETTINGS frame, window size, priority)
- Ordered Headers: Browser-accurate header ordering for perfect fingerprint evasion
- Certificate Pinning: Custom TLS certificate validation
- DNS-over-TLS: Enhanced privacy with DoT support
- Proxy Support: HTTP, HTTPS, SOCKS4 and SOCKS5 proxy configurations with UDP support for HTTP/3
🚀 Performance & Reliability
- Connection Pooling: Efficient connection reuse with singleton pattern
- Automatic Retries: Configurable retry logic with custom status codes
- Response Caching: Built-in body caching for repeated access
- Streaming Support: Efficient handling of large responses and SSE
- Compression: Automatic decompression of gzip, deflate, brotli, and zstd responses
- Keep-Alive: Persistent connections with configurable parameters
🛠️ Developer Experience
- Standard Library Compatible: Convert to
net/http.Clientfor third-party library integration - Fluent API: Chainable methods for elegant code
- Middleware System: Extensible request/response/client middleware with priority support
- Type Safety: Strong typing with generics support via enetx/g
- Debug Mode: Comprehensive request/response debugging
- Error Handling: Result type pattern for better error management
- Context Support: Full context.Context integration for cancellation and timeouts
📦 Installation
go get -u github.com/enetx/surf
Required Go version: 1.25+
🔄 Standard Library Compatibility
Surf provides seamless integration with Go's standard net/http package, allowing you to use Surf's advanced features with any library that expects a standard *http.Client.
// Create a Surf client with advanced features
surfClient := surf.NewClient().
Builder().
Impersonate().Chrome().
Session().
Build().
Unwrap()
// Convert to standard net/http.Client
stdClient := surfClient.Std()
// Use with any third-party library
// Example: AWS SDK, Google APIs, OpenAI client, etc.
resp, err := stdClient.Get("https://api.example.com")
Preserved Features When Using Std():
- ✅ JA3/TLS fingerprinting
- ✅ HTTP/2, HTTP/3 settings && fingerprinting
- ✅ Browser impersonation headers
- ✅ Ordered headers
- ✅ Cookies and sessions
- ✅ Proxy configuration
- ✅ Custom headers and User-Agent
- ✅ Timeout settings
- ✅ Redirect policies
- ✅ Request/Response middleware
Limitations with Std():
- ❌ Retry logic (implement at application level)
- ❌ Response body caching
- ❌ Remote address tracking
- ❌ Request timing information
🚀 Quick Start
Basic GET Request
package main
import (
"fmt"
"log"
"github.com/enetx/surf"
)
func main() {
resp := surf.NewClient().Get("https://api.github.com/users/github").Do()
if resp.IsErr() {
log.Fatal(resp.Err())
}
fmt.Println(resp.Ok().Body.String().Unwrap())
}
JSON Response Handling
type User struct {
Name string `json:"name"`
Company string `json:"company"`
Location string `json:"location"`
}
resp := surf.NewClient().Get("https://api.github.com/users/github").Do()
if resp.IsOk() {
var user User
resp.Ok().Body.JSON(&user)
fmt.Printf("User: %+v\n", user)
}
🎭 Browser Impersonation
Chrome Impersonation
client := surf.NewClient().
Builder().
Impersonate().
Chrome(). // Latest Chrome v145
Build().
Unwrap()
resp := client.Get("https://example.com").Do()
Firefox with Random OS
client := surf.NewClient().
Builder().
Impersonate().
RandomOS(). // Randomly selects Windows, macOS, Linux, Android, or iOS
Firefox(). // Latest Firefox v148
Build().
Unwrap()
Platform-Specific Impersonation
// iOS Chrome
client := surf.NewClient().
Builder().
Impersonate().
IOS().
Chrome().
Build().
Unwrap()
// Android Chrome
client := surf.NewClient().
Builder().
Impersonate().
Android().
Chrome().
Build().
Unwrap()
🚀 HTTP/3 & Complete QUIC Fingerprinting
Chrome HTTP/3 with Automatic Detection
// Automatic HTTP/3 with Chrome fingerprinting
client := surf.NewClient().
Builder().
Impersonate().Chrome().
ForceHTTP3(). // Auto-detects Chrome and applies appropriate HTTP/3 settings
Build().
Unwrap()
resp := client.Get("https://cloudflare-quic.com/").Do()
if resp.IsOk() {
fmt.Printf("Protocol: %s\n", resp.Ok().Proto) // HTTP/3.0
}
Firefox HTTP/3
// Firefox with HTTP/3 fingerprinting
client := surf.NewClient().
Builder().
Impersonate().Firefox().
ForceHTTP3(). // Auto-detects Firefox and applies Firefox HTTP/3 settings
Build().
Unwrap()
resp := client.Get("https://cloudflare-quic.com/").Do()
Manual HTTP/3 Configuration
// Custom fingerprint settings
client := surf.NewClient().
Builder().
HTTP3Settings().Grease().Set().
Build().
Unwrap()
HTTP/3 Compatibility & Fallbacks
HTTP/3 automatically handles compatibility issues:
// With HTTP proxy - automatically falls back to HTTP/2
client := surf.NewClient().
Builder().
Proxy("http://proxy:8080"). // HTTP proxies incompatible with HTTP/3
ForceHTTP3(). // Will use HTTP/2 instead
Build().
Unwrap()
// With SOCKS5 proxy - HTTP/3 works over UDP
client := surf.NewClient().
Builder().
Proxy("socks5://127.0.0.1:1080"). // SOCKS5 UDP proxy supports HTTP/3
ForceHTTP3(). // Will use HTTP/3 over SOCKS5
Build().
Unwrap()
// With DNS settings - works seamlessly
client := surf.NewClient().
Builder().
DNS("8.8.8.8:53"). // Custom DNS works with HTTP/3
ForceHTTP3().
Build().
Unwrap()
// With DNS-over-TLS - works seamlessly
client := surf.NewClient().
Builder().
DNSOverTLS().Google(). // DoT works with HTTP/3
ForceHTTP3()
Build().
Unwrap()
Key HTTP/3 Features:
- ✅ Complete QUIC Fingerprinting: Full Chrome and Firefox QUIC transport parameter matching
- ✅ Header Ordering: Perfect browser-like header sequence preservation
- ✅ SOCKS5 UDP Support: HTTP/3 works seamlessly over SOCKS5 UDP proxies
- ✅ Automatic Fallback: Smart fallback to HTTP/2 when HTTP proxies are configured
- ✅ DNS Integration: Custom DNS and DNS-over-TLS support
- ✅ JA4QUIC Support: Advanced QUIC fingerprinting with Initial Packet + TLS ClientHello
- ✅ Order Independence:
ForceHTTP3()works regardless of call order
🔧 Advanced Configuration
Custom JA3 Fingerprint
// Use specific browser versions
client := surf.NewClient().
Builder().
JA().
Chrome(). // Latest Chrome
Build().
Unwrap()
// Randomized fingerprints for evasion
client := surf.NewClient().
Builder().
JA().
Randomized(). // Random TLS fingerprint
Build().
Unwrap()
// With custom HelloID
client := surf.NewClient().
Builder().
JA().
SetHelloID(utls.HelloChrome_Auto).
Build().
Unwrap()
// With custom HelloSpec
client := surf.NewClient().
Builder().
JA().
SetHelloSpec(customSpec).
Build().
Unwrap()
HTTP/2 Configuration
client := surf.NewClient().
Builder().
HTTP2Settings().
HeaderTableSize(65536).
EnablePush(0).
InitialWindowSize(6291456).
MaxHeaderListSize(262144).
ConnectionFlow(15663105).
Set().
Build().
Unwrap()
HTTP/3 Configuration
client := surf.NewClient().
Builder().
HTTP3Settings().
QpackMaxTableCapacity(65536).
MaxFieldSectionSize(262144).
QpackBlockedStreams(100).
H3Datagram(1).
Grease().
Set().
Build().
Unwrap()
Proxy Configuration
// Single proxy
client := surf.NewClient().
Builder().
Proxy("http://proxy.example.com:8080").
Build().
Unwrap()
SOCKS5 UDP Proxy Support
Surf supports HTTP/3 over SOCKS5 UDP proxies, combining the benefits of modern QUIC protocol with proxy functionality:
// HTTP/3 over SOCKS5 UDP proxy
client := surf.NewClient().
Builder().
Proxy("socks5://127.0.0.1:1080").
Impersonate().Chrome().
ForceHTTP3(). // Uses HTTP/3 over SOCKS5 UDP
Build().
Unwrap()
// SOCKS5 with custom DNS resolution
client := surf.NewClient().
Builder().
DNS("8.8.8.8:53"). // Custom DNS resolver
Proxy("socks5://proxy:1080"). // SOCKS5 UDP proxy
ForceHTTP3(). // HTTP/3 over SOCKS5
Build().
Unwrap()
🔌 Middleware System
Request Middleware
client := surf.NewClient().
Builder().
With(func(req *surf.Request) error {
req.AddHeaders("X-Custom-Header", "value")
fmt.Printf("Request to: %s\n", req.GetRequest().URL)
return nil
}).
Build().
Unwrap()
Response Middleware
client := surf.NewClient().
Builder().
With(func(resp *surf.Response) error {
fmt.Printf("Response status: %d\n", resp.StatusCode)
fmt.Printf("Response time: %v\n", resp.Time)
return nil
}).
Build().
Unwrap()
Client Middleware
client := surf.NewClient().
Builder().
With(func(client *surf.Client) error {
// Modify client configuration
client.GetClient().Timeout = 30 * time.Second
return nil
}).
Build().
Unwrap()
📤 Request Types
POST with JSON
user := map[string]string{
"name": "John Doe",
"email": "[email protected]",
}
resp := surf.NewClient().
Post("https://api.example.com/users").
Body(user).
Do()
Form Data
// Standard form data (field order not guaranteed)
formData := map[string]string{
"username": "john",
"password": "secret",
}
resp := surf.NewClient().
Post("https://example.com/login").
Body(formData).
Do()
// Ordered form data (preserves field insertion order)
orderedForm := g.NewMapOrd[string, string]()
orderedForm.Insert("username", "john")
orderedForm.Insert("password", "secret")
orderedForm.Insert("remember_me", "true")
resp := surf.NewClient().
Post("https://example.com/login").
Body(orderedForm).
Do()
File Upload
// Single file upload
mp := surf.NewMultipart().
File("file", g.NewFile("/path/to/file.pdf"))
resp := surf.NewClient().
Post("https://api.example.com/upload").
Multipart(mp).
Do()
// With additional form fields
mp := surf.NewMultipart().
Field("description", "Important document").
Field("category", "reports").
File("file", g.NewFile("/path/to/file.pdf"))
resp := surf.NewClient().
Post("https://api.example.com/upload").
Multipart(mp).
Do()
Multipart Form
// Simple multipart form with fields only
mp := surf.NewMultipart().
Field("field1", "value1").
Field("field2", "value2")
resp := surf.NewClient().
Post("https://api.example.com/form").
Multipart(mp).
Do()
// Advanced multipart with files from different sources
mp := surf.NewMultipart().
Field("description", "Multiple files").
File("document", g.NewFile("/path/to/doc.pdf")). // Physical file
FileBytes("data", "data.json", g.Bytes(`{"key": "value"}`)). // Bytes with custom filename
FileString("text", "note.txt", "Hello, World!"). // String content
FileReader("stream", "upload.bin", someReader). // io.Reader
ContentType("application/pdf") // Custom Content-Type for last file
resp := surf.NewClient().
Post("https://api.example.com/upload").
Multipart(mp).
Do()
🔄 Session Management
Persistent Sessions
client := surf.NewClient().
Builder().
Session(). // Enable cookie jar
Build().
Unwrap()
// Login
client.Post("https://example.com/login").Body(credentials).Do()
// Subsequent requests will include session cookies
resp := client.Get("https://example.com/dashboard").Do()
Manual Cookie Management
// Set cookies
cookies := []*http.Cookie{
{Name: "session", Value: "abc123"},
{Name: "preference", Value: "dark_mode"},
}
resp := surf.NewClient().
Get("https://example.com").
AddCookies(cookies...).
Do()
// Get cookies from response
if resp.IsOk() {
for _, cookie := range resp.Ok().Cookies {
fmt.Printf("Cookie: %s = %s\n", cookie.Name, cookie.Value)
}
}
📊 Response Handling
Status Code Checking
resp := surf.NewClient().Get("https://api.example.com/data").Do()
if resp.IsOk() {
switch {
case resp.Ok().StatusCode.IsSuccess():
fmt.Println("Success!")
case resp.Ok().StatusCode.IsRedirection():
fmt.Println("Redirected to:", resp.Ok().Location())
case resp.Ok().StatusCode.IsClientError():
fmt.Println("Client error:", resp.Ok().StatusCode)
case resp.Ok().StatusCode.IsServerError():
fmt.Println("Server error:", resp.Ok().StatusCode)
}
}
Body Processing
resp := surf.NewClient().Get("https://example.com/data").Do()
if resp.IsOk() {
body := resp.Ok().Body
// As string (returns g.Result[g.String])
if content := body.String(); content.IsOk() {
fmt.Println(content.Ok())
}
// As bytes (returns g.Result[g.Bytes])
if data := body.Bytes(); data.IsOk() {
fmt.Println(len(data.Ok()))
}
// UTF-8 conversion (returns g.Result[g.String])
if utf8Content := body.UTF8(); utf8Content.IsOk() {
fmt.Println(utf8Content.Ok())
}
// Check content
if body.Contains("success") {
fmt.Println("Request succeeded!")
}
// Save to file
err := body.Dump("response.html")
}
Streaming Large Responses
resp := surf.NewClient().Get("https://example.com/large-file").Do()
if resp.IsOk() {
stream := resp.Ok().Body.Stream()
defer stream.Close()
scanner := bufio.NewScanner(stream)
for scanner.Scan() {
fmt.Println(scanner.Text())
}
}
Server-Sent Events (SSE)
resp := surf.NewClient().Get("https://example.com/events").Do()
if resp.IsOk() {
resp.Ok().Body.SSE(func(event *sse.Event) bool {
fmt.Printf("Event: %s, Data: %s\n", event.Event, event.Data)
return true // Continue reading (false to stop)
})
}
🔍 Debugging
Request/Response Debugging
resp := surf.NewClient().
Get("https://api.example.com").
Do()
if resp.IsOk() {
resp.Ok().Debug().
Request(). // Show request details
Response(true). // Show response with body
Print()
}
TLS Information
resp := surf.NewClient().Get("https://example.com").Do()
if resp.IsOk() {
if tlsInfo := resp.Ok().TLSGrabber(); tlsInfo != nil {
fmt.Printf("TLS Version: %s\n", tlsInfo.TLSVersion)
fmt.Printf("Server Name: %s\n", tlsInfo.ExtensionServerName)
fmt.Printf("Fingerprint: %s\n", tlsInfo.FingerprintSHA256)
fmt.Printf("Common Name: %v\n", tlsInfo.CommonName)
fmt.Printf("Organization: %v\n", tlsInfo.Organization)
}
}
⚡ Performance Optimization
Connection Reuse
// Create a reusable client
client := surf.NewClient().
Builder().
Impersonate().
Chrome().
Build().
Unwrap()
// Reuse for multiple requests
for i := 0; i < 100; i++ {
resp := client.Get("https://api.example.com/data").Do()
// Process response
}
// Clean up when done
defer client.CloseIdleConnections()
Response Caching
client := surf.NewClient().
Builder().
CacheBody(). // Enable body caching
Build().
Unwrap()
resp := client.Get("https://api.example.com/data").Do()
if resp.IsOk() {
// First access reads from network
data1 := resp.Ok().Body.Bytes().Unwrap()
// Subsequent accesses use cache
data2 := resp.Ok().Body.Bytes().Unwrap() // No network I/O
}
Retry Configuration
client := surf.NewClient().
Builder().
Retry(3, 2*time.Second). // Max 3 retries, 2 second wait
Build().
Unwrap()
🌐 Advanced Features
H2C (HTTP/2 Cleartext)
// Enable HTTP/2 without TLS
client := surf.NewClient().
Builder().
H2C().
Build().
Unwrap()
resp := client.Get("http://localhost:8080/h2c-endpoint").Do()
Custom Headers Order
// Control exact header order for fingerprinting evasion
headers := g.NewMapOrd[g.String, g.String]()
headers.Insert("User-Agent", "Custom/1.0")
headers.Insert("Accept", "*/*")
headers.Insert("Accept-Language", "en-US")
headers.Insert("Accept-Encoding", "gzip, deflate")
client := surf.NewClient().
Builder().
SetHeaders(headers). // Headers will be sent in this exact order
Build().
Unwrap()
Custom DNS Resolver
client := surf.NewClient().
Builder().
DNS("8.8.8.8:53"). // Use Google DNS
Build().
Unwrap()
DNS-over-TLS
client := surf.NewClient().
Builder().
DNSOverTLS().Cloudflare(). // Cloudflare DoT
Build().
Unwrap()
Unix Domain Sockets
client := surf.NewClient().
Builder().
UnixSocket("/var/run/docker.sock").
Build().
Unwrap()
resp := client.Get("http://localhost/v1.41/containers/json").Do()
Network Interface Binding
client := surf.NewClient().
Builder().
InterfaceAddr("192.168.1.100"). // Bind to specific IP
Build().
Unwrap()
Raw HTTP Requests
rawRequest := `GET /api/data HTTP/1.1
Host: example.com
User-Agent: Custom/1.0
Accept: application/json
`
resp := surf.NewClient().
Raw(g.String(rawRequest), "https").
Do()
📚 API Reference
Client Methods
| Method | Description |
|---|---|
NewClient() | Creates a new HTTP client with defaults |
Get(url) | Creates a GET request |
Post(url) | Creates a POST request |
Put(url) | Creates a PUT request |
Patch(url) | Creates a PATCH request |
Delete(url) | Creates a DELETE request |
Head(url) | Creates a HEAD request |
Options(url) | Creates an OPTIONS request |
Connect(url) | Creates a CONNECT request |
Trace(url) | Creates a TRACE request |
Raw(raw, scheme) | Creates a request from raw HTTP |
Builder() | Returns a new Builder for client configuration |
Std() | Convert to standard *net/http.Client |
CloseIdleConnections() | Closes idle connections while keeping client usable |
Close() | Completely shuts down the client and releases all resources |
Builder Methods
| Method | Description |
|---|---|
Impersonate() | Enable browser impersonation |
JA() | Configure JA3/JA4 fingerprinting |
HTTP2Settings() | Configure HTTP/2 parameters |
HTTP3Settings() | Configure HTTP/3 parameters |
H2C() | Enable HTTP/2 cleartext |
Proxy(proxy) | Set proxy configuration |
DNS(dns) | Set custom DNS resolver |
DNSOverTLS() | Configure DNS-over-TLS |
Session() | Enable cookie jar for sessions |
Timeout(duration) | Set request timeout |
MaxRedirects(n) | Set maximum redirects |
NotFollowRedirects() | Disable redirect following |
FollowOnlyHostRedirects() | Only follow same-host redirects |
ForwardHeadersOnRedirect() | Forward headers on redirects |
RedirectPolicy(fn) | Custom redirect policy function |
Retry(max, wait, codes...) | Configure retry logic |
CacheBody() | Enable response body caching |
With(middleware, priority...) | Add middleware |
BasicAuth(auth) | Set basic authentication |
BearerAuth(token) | Set bearer token authentication |
UserAgent(ua) | Set custom user agent |
SetHeaders(headers...) | Set request headers |
AddHeaders(headers...) | Add request headers |
AddCookies(cookies...) | Add cookies |
WithContext(ctx) | Add context |
ContentType(type) | Set content type |
GetRemoteAddress() | Track remote address |
DisableKeepAlive() | Disable keep-alive |
DisableCompression() | Disable compression |
ForceHTTP1() | Force HTTP/1.1 |
ForceHTTP2() | Force HTTP/2 |
ForceHTTP3() | Force HTTP/3 |
UnixSocket(path) | Use Unix socket |
InterfaceAddr(addr) | Bind to network interface |
Boundary(fn) | Custom multipart boundary generator |
Request Methods
| Method | Description |
|---|---|
Do() | Execute the request |
WithContext(ctx) | Add context to request |
Body(data) | Set request body (JSON, form data, bytes, string, io.Reader) |
SetHeaders(headers...) | Set request headers |
AddHeaders(headers...) | Add request headers |
AddCookies(cookies...) | Add cookies to request |
Multipart(mp) | Set multipart form data for request |
GetRequest() | Returns underlying *http.Request |
Multipart Methods
| Method | Description |
|---|---|
NewMultipart() | Creates a new Multipart builder |
Field(name, value) | Adds a form field |
File(fieldName, file) | Adds a file from *g.File |
FileReader(fieldName, fileName, reader) | Adds a file from io.Reader |
FileString(fieldName, fileName, content) | Adds a file from string content |
FileBytes(fieldName, fileName, data) | Adds a file from byte slice |
ContentType(ct) | Sets custom Content-Type for the last added file |
FileName(name) | Overrides filename for the last added file |
Retry() | Buffers multipart body for retry support |
Response Properties
| Property | Type | Description |
|---|---|---|
StatusCode | StatusCode | HTTP status code |
Headers | Headers | Response headers |
Cookies | Cookies | Response cookies |
Body | *Body | Response body |
URL | *url.URL | Final URL after redirects |
Time | time.Duration | Request duration |
ContentLength | int64 | Content length |
Proto | string | HTTP protocol version |
Attempts | int | Number of retry attempts |
Response Methods
| Method | Description |
|---|---|
Debug() | Returns debug info for request/response inspection |
Location() | Returns the Location header (redirect URL) |
TLSGrabber() | Returns TLS connection information |
Referer() | Returns HTTP Referer header from original request |
GetResponse() | Returns underlying *http.Response |
GetCookies(url) | Returns cookies for a specific URL |
SetCookies(url, cookies) | Stores cookies in client's cookie jar |
RemoteAddress() | Returns remote server address |
Body Methods
| Method | Description |
|---|---|
String() | Get body as string (returns g.Result[g.String]) |
Bytes() | Get body as bytes (returns g.Result[g.Bytes]) |
JSON(v) | Decode JSON into struct |
XML(v) | Decode XML into struct |
UTF8() | Convert to UTF-8 (returns g.Result[g.String]) |
Stream() | Get StreamReader for streaming (with Close support) |
SSE(fn) | Process Server-Sent Events |
Dump(file) | Save to file |
Contains(pattern) | Check if contains pattern |
Limit(n) | Limit body size |
WithContext(ctx) | Set context for cancellation of read operations |
Close() | Close body reader |
🤝 Contributing
Contributions are welcome! Please feel free to submit a Pull Request. For major changes, please open an issue first to discuss what you would like to change.
- Fork the repository
- Create your feature branch (
git checkout -b feature/AmazingFeature) - Commit your changes (
git commit -m 'Add some AmazingFeature') - Push to the branch (
git push origin feature/AmazingFeature) - Open a Pull Request
❤️ Support / Sponsorship
If you enjoy Surf and want to help keep development going, you can support the project with crypto donations:
| USDT | TON | SOL | BTC | ETH |
|---|---|---|---|---|
Thank you for your support!
📄 License
This project is licensed under the MIT License - see the LICENSE file for details.
🙏 Acknowledgments
- Built with enetx/http for enhanced HTTP functionality
- HTTP/3 support and complete QUIC fingerprinting powered by QUIC-GO
- TLS fingerprinting powered by uTLS
- Generic utilities from enetx/g
📞 Support
- Issues: GitHub Issues
- Discussions: GitHub Discussions
- Documentation: pkg.go.dev
Made with ❤️ by the Surf contributors