Сreate a slug system with Strapi V4.

1 Create a new file following this structure
 

./src/api/[api-name]/content-types/[content]/lifecycles.js

We can control the lifecycle on this file, so we can transform our information on several events. Check the documentation.

2 Install slugify dependency
 

yarn add slugify

3 Add code on your lifecycle file.
 

const slugify = require("slugify");

module.exports = {
  beforeCreate(event) {
    const { data } = event.params;
    if (data.title) {
      data.slug = slugify(data.title, { lower: true });
    }
  },
  beforeUpdate(event) {
    const { data } = event.params;
    if (data.title) {
      data.slug = slugify(data.title, { lower: true });
    }
  },
};

As you can see the slug is based on our title.