diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
new file mode 100644
index 0000000..5f30705
--- /dev/null
+++ b/.github/copilot-instructions.md
@@ -0,0 +1,75 @@
+# Copilot Instructions
+
+## Project Overview
+
+Turtle-Hook is a service that updates a SPARQL endpoint to reflect changes to RDF-Turtle files in a GitHub repository. It provides a webhook and web/REST interface using the [ghact](https://deno.land/x/ghact) library.
+
+## Technology Stack
+
+- **Runtime**: [Deno](https://deno.land/) (TypeScript runtime)
+- **Language**: TypeScript
+- **HTTP Framework**: ghact (GitHub Action/Webhook framework for Deno)
+- **Triple Store**: Any SPARQL 1.1 compliant endpoint
+- **Container**: Docker
+
+## Project Structure
+
+- `src/` - Source code
+  - `main.ts` - Application entry point, creates GHActServer
+  - `worker.ts` - Worker that processes jobs (LOAD/DROP SPARQL operations)
+  - `deps.ts` - External dependencies (re-exports from ghact)
+- `config/` - Configuration files
+  - `config.ts` - Application configuration (SPARQL endpoint, source repository)
+- `Dockerfile` - Container definition
+- `.devcontainer/` - VS Code dev container configuration
+
+## Code Style and Conventions
+
+- Use TypeScript with Deno
+- Import external dependencies through `src/deps.ts`
+- Use URL imports for Deno modules (e.g., `https://deno.land/x/...`)
+- Follow Deno's built-in formatter and linter (`deno fmt`, `deno lint`)
+- Prefer `const` over `let` where possible
+- Use arrow functions for callbacks and short functions
+
+## Running the Application
+
+```bash
+# Run the main server
+deno run --allow-net --allow-read --allow-write --allow-run=git --allow-env src/main.ts
+
+# Format code
+deno fmt
+
+# Lint code
+deno lint
+
+# Cache dependencies
+deno cache src/deps.ts
+```
+
+## Docker
+
+```bash
+# Build the Docker image
+docker build -t turtle-hook .
+
+# Run the container
+docker run -p 4505:4505 turtle-hook
+```
+
+## Key Concepts
+
+- **SPARQL Operations**: The worker handles three types of operations on `.ttl` files:
+  - `LOAD` - For newly added files
+  - `DROP` - For removed files
+  - `UPDATE` (DROP + LOAD) - For modified files
+- **Graph URIs**: Generated from the file name, prefixed with `https://treatment.plazi.org/id`. This prefix should not be changed as removing previous versions depends on it remaining consistent.
+- **Jobs**: Processed asynchronously via Web Workers
+
+## Contribution Guidelines
+
+- Keep dependencies minimal and use Deno-compatible modules
+- Test changes with Docker build to ensure compatibility
+- Maintain backwards compatibility with the SPARQL endpoint interface
+- Update `src/deps.ts` when adding new external dependencies