Introduction

GitHub Copilot now supports Bring Your Own Key (BYOK), allowing developers to connect local or self-hosted AI models directly into VS Code.

This means you can run coding assistants locally using tools like Ollama (offline AI) without sending prompts to external providers.

• Architecture
• Step 0 - Prerequisites
• Step 1 - Install Ollama
• Step 2 - Pull a Model
• Step 3 - Test the Model
• Step 4 - Confirm API Endpoint
• Step 5 - Configure VS Code
• Step 6 - Select Your Model
• Step 7 - Remote Access (Optional)
• Step 8 - Configure Nginx Reverse Proxy (Optional)
• Step 9 - Testing

Architecture

VS Code
   ↓
GitHub Copilot Chat (BYOK)
   ↓
Ollama API
   ↓
Local LLM

Example:

VS Code → localhost:11434 → Qwen2.5-Coder

Step 0 - Prerequisites

• Ollama v0.18.3+
• VS Code 1.113+
• GitHub Copilot Chat extension 0.41.0+

Step 1 - Install Ollama

Linux

Official:

sudo curl -fsSL https://ollama.com/install.sh | sh

Reference: https://docs.ollama.com/integrations/vscode

Verify

ollama --version

Start service:

systemctl enable ollama --now

Check service:

systemctl status ollama

Step 2 - Pull a Model

Best Starting Models

Note: Hardware requirements vary depending on quantisation level and context size.

• LLMs can run on CPU-only systems, but response latency may increase significantly depending on model size and quantisation.
• For practical coding assistance, GPU acceleration is strongly recommended for models larger than 7B–14B parameters.

Step 3 - Test the Model

Run:

ollama pull phi4-mini

ollama run phi4-mini

You should get an interactive prompt.

Step 4 - Confirm API Endpoint

Ollama automatically exposes:

http://localhost:11434

Test:

curl http://localhost:11434/api/tags

You should see JSON listing models.

Step 5 - Configure VS Code

Open:

Ctrl+Shift+P 
(macOS: Command+Shift+P)

Run:

Chat: Manage Language Models

Then:

Add Models → Ollama

NOTE: this section must show “tools”

Otherwise GitHub Copilot cannot select

VS Code should auto-detect:

http://localhost:11434

Or, if using a remote Ollama server (not run locally) - see step 8

https://ollama.internal.domain:443

Reference: https://docs.ollama.com/integrations/vscode

Step 6 - Select Your Model

Inside Copilot Chat (set session target) select Local:

• Open model picker

• Choose (other models Ollama):

  • qwen2.5-coder
  • etc…

Now your prompts go to your local model.

Important Limitation

This currently applies mainly to:

• ✅ Chat
• ✅ Agent mode
• ✅ AI interactions

But NOT fully to:

• ❌ inline autocomplete

Homelab Setup

Small Setup

High-level overview

Mini PC / NUC
Debian Server
Ollama
Qwen2.5-Coder 14B
Tailscale

Step 7 - Remote Access (Optional)

If your inference server is elsewhere (not hosted locally):

Example:

http://ai-node:11434

or

https://ollama.internal.domain

Then configure Ollama accordingly.

SECURITY (VERY IMPORTANT)

Do NOT expose Ollama publicly.

Bad:

0.0.0.0:11434

without auth/firewall.

Use:

• Tailscale
• WireGuard
• reverse proxy auth
• firewall ACLs

There are already reports of exposed Ollama servers online.

Step 8 - Configure Nginx Reverse Proxy (Optional)

You can skip this step if testing

If you plan to access Ollama remotely, it is recommended to place it behind a reverse proxy rather than exposing the API directly.

VS Code
   ↓
HTTPS
   ↓
Nginx Reverse Proxy
   ↓
Ollama API
   ↓
Local Model

Install Nginx

Debian/Ubuntu:

sudo apt update
sudo apt install nginx -y

RHEL/AlmaLinux:

sudo dnf install nginx -y

Enable and start the service:

sudo systemctl enable --now nginx

Verify:

systemctl status nginx

Create Reverse Proxy Configuration

Create a new Nginx site configuration:

sudo vim /etc/nginx/conf.d/ollama.conf

Example configuration:

This step uses HTTP for testing (not recommended for production)

server {
    listen 80;
    server_name ollama.internal.domain;

    location / {
        proxy_pass http://127.0.0.1:11434;

        proxy_http_version 1.1;

        proxy_set_header Host $host;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Test configuration:

sudo nginx -t

Reload Nginx:

sudo systemctl reload nginx

Verify Reverse Proxy

Test locally:

curl http://localhost/api/tags

Or remotely (DNS must resolve for this to work):

curl http://ollama.internal.domain/api/tags

You should receive JSON output listing available models.

Step 9 - Testing

Inside VS Code Copilot Chat:

1. Select the Ollama model
2. Ensure the session target is set to Local
3. Open a source file
4. Highlight a small code block
5. Test prompts such as:

Explain this function

or:

Suggest improvements

If successful:

• responses should come from the local model
• Ollama logs will show /v1/chat/completions
• no external provider API keys are required

Monitor logs:

journalctl -u ollama -f

Example successful request:

POST "/v1/chat/completions"

References

Official VS Code Docs

VS Code Language Models Documentation

Official Ollama VS Code Integration

Ollama VS Code Integration Docs

GitHub Copilot BYOK Docs

GitHub Copilot BYOK Documentation

VS Code BYOK Announcement

Expanding Model Choice in VS Code with BYOK

vLLM

vLLM GitHub Repository

Ollama

https://ollama.com