Pup

Pup is a powerful universal process manager developed with Deno, designed to keep your scripts, applications and services alive.

  • Cross-platform: Manage processes for various languages and platforms, such as Deno, Node.js, Python, and Ruby on Windows, macOS, and Linux.
  • Process management: Define, control, and manage your processes with simple commands and configuration options.
  • Autostart, watch or cron: Set up processes to start automatically, on a schedule (using cron expressions), or when files change.
  • Service management: Install Pup instances as a system service, supporting sysvinit, systemd, upstart, macOS, and Windows.
  • Clustering and load balancing: Scale your application seamlessly with built-in clustering and load balancing capabilities.
  • Plugins: Extend Pup's functionality with custom plugins for additional features and integrations.
  • Process Telemetry and IPC: Pup can gather telemetry data from Deno client processes, such as memory usage and current working directory, providing deeper insights into managed processes. The telemetry feature also enables inter-process communication, allowing connected processes to interact with one another.
  • Rest API: Control and monitor Pup from third party solutions using the build in Rest API.

Note Programmatic usage, process telemetry, and IPC are currently available only when running Deno client processes.

Pup is centered on a single configuration file, pup.json, which manages all aspects of the processes to be executed, including their execution methods and logging handling. JSON5 syntax is supported.

Quick Start

Installation

To install Pup, open your terminal and execute the following command:

deno run -Ar jsr:@pup/pup@1.0.0-rc.36 setup --channel prerelease

This command downloads the latest version of Pup and installs it on your system. The --channel prerelease option is included as there is no stable version of Pup yet. Read more abour release channels here.

Configuration and Usage

Pup revolves around instance configuration files, where each managed process belongs to an instance defined by a pup.json. This file can either be created manually, or by the command line helpers used below:

  1. To create a simple instances running a single process:

    pup init --id "my-server" --autostart --cmd "deno run -A server.ts"

    If you intend to create multiple pup instances on the same server, you can pass an instance name through --name my-instance-name. This name will also be used as the system service name.

  2. (Optional) In case you have an additional task to execute, such as a cleanup script, you can make use of pup append. The following example shows how to add an extra task that use the cron start policy:

    pup append --id "my-task" --cmd "deno run -A task.ts" --cron "0 0 * * * *"

  3. (Optional) Test your instance by running it foreground using pup run (exit by pressing CTRL+C):

  4. To make your instance run at boot, enable it using pup enable-service.

    Will by default use the instance name for service name, which defaults to pup. You can override by passing -n my-custom-name.

  5. To stream the logs from a running instance, use the command pup monitor. To show historic logs, use pup logs.

    Will by default use the instance name for service name, which defaults to pup. You can override by passing -n my-custom-name.

Single command example

It is possible to use pup without a pup.json or system service.

Keeping a process alive

To keep a process alive temporary, use pup run with --cmd and a start policy

pup run --autostart --cmd "deno run server.ts"

Restarting a process on filesystem changes

To restart if any file changes withing the current directory, add --watch <watched-path>:

pup run --autostart --cmd "deno run server.ts" --watch .