# ADR-0002: Separate Executors From Schedulers

## Status

Accepted

## Context

EmboFlow needs to support multiple runtime modes now and later:

- direct Python execution
- Docker-isolated execution
- HTTP-based execution
- local scheduling
- future Kubernetes scheduling
- future Volcano scheduling

If execution logic and scheduling logic are coupled together, migration from single-host operation to cluster operation becomes costly.

## Decision

The architecture will separate:

- Executor: how node logic runs
- Scheduler: where and under what dispatch policy tasks run

V1 executors:

- Python
- Docker
- HTTP

V1 scheduler:

- Local

Reserved future schedulers:

- Kubernetes
- Volcano

## Consequences

### Positive

- Cleaner evolution path
- Better runtime abstraction
- Less refactoring required for cluster migration

### Negative

- Slightly more abstraction in V1 than the immediate deployment requires

## Notes

User-injected code should default to Docker execution, while trusted platform logic may use Python execution.