How to start development server

thejon_07 · December 15, 2025, 8:38am

Hi everyone,
I am new to the Processing Foundation. I am facing issues while starting the development server for the p5.js repository. Can anyone help me with this? Thank you.

glv · December 15, 2025, 10:41pm

Hello @thejon_07 ,

Are you referring to this:

github.com/processing/p5.js-website

docs/technical_overview.md

main

# Technical Overview

## Getting Started with Development

### Setup

1. Make sure you have [node and npm installed on your machine](https://nodejs.org/en/learn/getting-started/how-to-install-nodejs).
2. Clone this repo by typing git clone https://github.com/processing/p5.js-website/ in your terminal. (You can also use [GitHub Desktop](https://desktop.github.com/)).
3. Then install the project's dependencies with:

```shellsession
npm install
```

### Running

Running this will start up a local dev server and print out the address in your terminal (for example: http://localhost:4321/). Open that page in your browser to see the website.

```shellsession
npm run dev

This file has been truncated. show original

I am having issues as well:

Terminal

D:\repository\p5.js-website>npm run dev

p5.js-website@0.0.1 dev
astro dev

19:48:31 [astro-mermaid] Setting up Mermaid integration
19:48:31 [astro-mermaid] Existing rehype plugins:
19:48:31 [astro-mermaid] Skipping ELK support
19:48:31 [types] Generated 1ms

Auto-generating collections for folders in “src/content/” that are not defined as collections.
This is deprecated, so you should define these collections yourself in “src/content.config.ts”.
The following collections have been auto-generated: ui

19:48:34 [content] Syncing content
19:48:34 [WARN] [glob-loader] No files found matching “/*{.md,.mdx},!//**/{.md,.mdx},!**/*{.md,.mdx}” in directory “src\content\ui”
[InvalidContentEntryDataError] libraries → en/AnimatorJs data does not match collection schema.

featuredImage: Featured image must be 1500x1000

Hint:
See Content collections | Docs for more information on content schemas.
Error reference:
Content entry data does not match schema. | Docs
Location:
D:\repository\p5.js-website\src\content\libraries\en\AnimatorJs.yaml:0:0
Stack trace:
at getEntryDataAndImages (file:///D:/repository/p5.js-website/node_modules/astro/dist/content/utils.js:161:26)
at async syncData (file:///D:/repository/p5.js-website/node_modules/astro/dist/content/loaders/glob.js:94:28)

:)

Topic		Replies	Views
How to check change code works Development	9	229	December 12, 2023
How to preview changes made in p5.js repository at ps.js web-editor at my localhost Development	6	891	February 26, 2021
P5.js website example pages not building Development	0	387	December 25, 2020
Is there a way to running my P5.js code locally without a webserver? Beginners	1	1753	November 8, 2020
Query regarding to start contribution Development	2	583	January 17, 2020

How to start development server

Related topics