Overview

dfxd is the long-running daemon of the dfx project.

Its primary job is to supervise and manage one or more dfx instances on the local machine. It provides a stable control plane so that instances can be created, started, stopped, queried, and reconfigured without tying that responsibility to a single interactive dfx process.

Responsibilities

dfxd typically provides:

• instance lifecycle management (create/start/stop/kill/remove),
• process supervision (spawn and monitor dfx instances),
• control interface for external tools (primarily dfx-ctl),
• centralized configuration for daemon-level defaults and policies.

In other words: dfx executes graphs, while dfxd manages executors.

Control interface

dfxd exposes a control API over a Unix domain socket.

This interface is designed to be:

• local-machine friendly (no network exposure by default),
• scriptable (machine-readable request/response),
• suitable for orchestration tools and CI environments.

dfx-ctl is the canonical client for this interface.

Instances

An instance is a managed dfx process with its own:

• graph configuration and runtime state,
• control socket,
• lifecycle independent from other instances.

dfxd keeps track of these instances and provides an API to:

• enumerate them,
• reach their control endpoints,
• apply policies consistently across them.

What dfxd is (and is not)

dfxd is:

• a daemon / supervisor for dfx processes,
• the recommended way to run multiple managed dfx instances,
• the main service endpoint for operational control via dfx-ctl.

dfxd is not:

• a graph execution engine (that is dfx),
• a UI application.