System proxy configuration

What is system proxy

System proxy configuration tells your operating system to route all network traffic through SlipStream’s HTTP proxy server. This enables system-wide VPN functionality without requiring individual application configuration.

When system proxy is enabled, most applications on your computer will automatically use the VPN connection without additional setup.

How it works

SlipStream GUI creates a multi-layer proxy architecture:

Your Applications
    ↓ HTTP/HTTPS
HTTP Proxy Server (127.0.0.1:8080)
    ↓ SOCKS5 Protocol
SOCKS5 Client (127.0.0.1:5201)
    ↓ Encrypted Tunnel
SlipStream VPN Server

The system proxy configuration points your OS to the HTTP Proxy Server, which then routes traffic through the encrypted VPN tunnel.

Auto-configuration feature

SlipStream GUI can automatically configure your system proxy settings when you start the VPN.

Enabling auto-configuration

Locate the toggle

In the settings section, find the “System Proxy” toggle switch.

Enable the toggle

Click the toggle to enable automatic system proxy configuration.The setting is saved immediately to settings.json.

Start the VPN

When you start the VPN with this toggle enabled, SlipStream GUI will automatically:

Configure your OS proxy settings
Set HTTP proxy to 127.0.0.1:8080
Set HTTPS proxy to 127.0.0.1:8080
Apply bypass list if configured

Verify configuration

The status panel will show “System Proxy: Configured” when successful.

The app only modifies system proxy settings that it configured itself, ensuring it doesn’t interfere with other proxy configurations.

Automatic cleanup

When you stop the VPN, SlipStream GUI will:

Restore your previous proxy settings
Only unconfigure proxies that match its own configuration (127.0.0.1:8080)
Leave other proxy configurations untouched

The app tracks which proxies it configured in settings.json to ensure safe cleanup even after crashes or unexpected shutdowns.

Manual configuration

If you prefer manual control or encounter issues with auto-configuration, you can manually set up the system proxy.

macOS manual setup

Open System Settings

Go to System Settings → Network

Select your network

Click your active network connection (Wi-Fi or Ethernet)

Open Proxies settings

Click Details… → Proxies tab

Configure HTTP and HTTPS proxies

Check Web Proxy (HTTP)
Server: 127.0.0.1
Port: 8080
Check Secure Web Proxy (HTTPS)
Server: 127.0.0.1
Port: 8080

Set bypass list (optional)

In the Bypass proxy settings for these Hosts & Domains field, add domains from your bypass list.

Apply settings

Click OK to save

Windows manual setup

Open Proxy Settings

Go to Settings → Network & Internet → Proxy

Enable manual proxy

Under Manual proxy setup, toggle on Use a proxy server

Enter proxy details

Address: 127.0.0.1
Port: 8080

Set bypass list (optional)

In the Use the proxy server except for addresses that start with… field, enter:

<local>

Add additional bypass entries separated by semicolons if needed.

Save settings

Click Save

On Windows, run SlipStream GUI as Administrator for best results with automatic proxy configuration.

Linux manual setup (GNOME)

Open Network Settings

Go to Settings → Network → Network Proxy

Select Manual mode

Choose Manual from the method dropdown

Configure HTTP and HTTPS

HTTP Proxy: 127.0.0.1 Port: 8080
HTTPS Proxy: 127.0.0.1 Port: 8080

Set bypass list (optional)

In the Ignore Hosts field, add domains that should bypass the proxy

Apply settings

Close the settings window (changes are saved automatically)

Proxy ports

SlipStream GUI uses two local ports for proxy functionality:

Port 8080 - HTTP Proxy

Primary proxy port - This is what you’ll configure in your system settings.

Address: 127.0.0.1:8080 (localhost only) or 0.0.0.0:8080 (network accessible)
Protocol: HTTP/HTTPS proxy
Purpose: Accepts HTTP and HTTPS requests from applications and forwards them through the VPN
Network sharing: Listens on 0.0.0.0 to allow mobile devices on the same network to connect

Port 5201 - SOCKS5

Address: 127.0.0.1:5201
Protocol: SOCKS5 proxy
Purpose: Created by the SlipStream client binary; the HTTP proxy on port 8080 forwards traffic here
Note: Not typically used directly by applications

Ensure ports 8080 and 5201 are not in use by other applications. If you see “Address already in use” errors, close conflicting applications or change the port configuration.

Bypass list for split tunneling

The proxy bypass list allows you to exclude specific domains or IP addresses from going through the VPN. This is useful for:

Accessing local network resources
Excluding specific services from the VPN
Improving performance for local traffic
Split tunneling scenarios

Configuring the bypass list

Find the Proxy Bypass List setting

In the Configuration section, locate the “Proxy Bypass List” text area.

Enter bypass entries

Add domains or addresses, one per line. Examples:

*.google.com
192.168.1.0/24
localhost
127.0.0.1
*.internal.company.com
local-server

Save the list

Click outside the text area or press Ctrl/Cmd+Enter to save.

Apply changes

If the VPN is running, stop and restart it to apply the new bypass list.

Bypass list syntax

Wildcards:

*.google.com          # Matches all Google subdomains
*.internal.*          # Matches any domain with 'internal' in it

IP ranges (CIDR notation):

192.168.1.0/24        # Entire local subnet
10.0.0.0/8            # Private network range

Exact matches:

localhost             # Localhost only
127.0.0.1             # Loopback IP
my-server.local       # Specific hostname

Windows-specific:

<local>               # All local addresses (Windows)

The bypass list is stored in settings.json and persists between sessions. It’s also included when you save workspace presets.

Platform-specific notes

macOS

Permissions
Network services
Troubleshooting

System proxy configuration requires administrator privileges
macOS will prompt for your password when enabling system proxy
The app uses networksetup command-line tool

If auto-configuration fails:

Ensure you’re not behind a corporate proxy
Check that networksetup commands aren’t blocked
Try manual configuration instead

Windows

Administrator privileges
Dual proxy configuration
Previous settings restoration

For best results, run SlipStream GUI as Administrator on Windows.

This ensures:

WinHTTP proxy can be configured
WinINET (user proxy) can be set
Registry changes are allowed

The app captures your previous proxy settings before making changes:

ProxyEnable state
ProxyServer value
ProxyOverride (bypass list)

These are restored when you disable the proxy or stop the VPN.

Linux

GNOME (gsettings)
Other desktop environments
Application-specific

Auto-configuration works with:

GNOME Desktop Environment
Uses gsettings for configuration
Sets both HTTP and HTTPS proxies
Applies ignore-hosts for bypass list

For non-GNOME environments:

Manual configuration required

Set environment variables if needed:

export HTTP_PROXY="http://127.0.0.1:8080"
export HTTPS_PROXY="http://127.0.0.1:8080"
export NO_PROXY="localhost,127.0.0.1"

Some Linux apps ignore system proxy settings:

Configure them individually to use 127.0.0.1:8080
Or set HTTP_PROXY environment variable when launching them

Troubleshooting