Design a hosted notebook platform for interactive code execution

Question

## Design a Hosted Notebook Platform for Interactive Code Execution

Design a cloud-hosted notebook platform similar to a managed Jupyter-style service. Users can create isolated workspaces, write and execute code interactively, persist notebook files, suspend compute when idle, and resume work quickly later.

The platform must support **500,000 concurrent users**.

Each user can manage one or more isolated workspaces. A workspace includes:

- A runtime environment for executing user code
- Persisted notebook files
- User-specific dependencies and environment metadata
- Workspace lifecycle state

The system must support the following workspace operations:

- Create a workspace
- Delete a workspace
- Suspend a workspace
- Resume a suspended workspace

The **resume operation should complete in under 5 seconds** for typical requests.

## Requirements

### Functional Requirements

1. Users can create isolated workspaces.
2. Users can open notebooks and execute code interactively.
3. Each workspace has its own runtime environment.
4. Notebook files must be persisted across suspend and resume.
5. Users can suspend a workspace to stop active compute.
6. Users can resume a suspended worksp

Accepted Answer

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