This results in faster page loads for cached content and less surface area for security vectors. It prevents site editing while enabled though.

Setting an environment variable named SERVERLESSWP_READ_ONLY_MODE to 1 or true in your project’s Vercel or Netlify settings and then redeploying the project will enable this. Switch it to 0 or false and redeploy to be able to edit the site again.

To set the duration of the cache control max-age in seconds, use the SERVERLESSWP_READ_ONLY_CACHE_MAX_AGE environment variable. It defaults to 86400 seconds (1 day).

When combined with SQLite + S3, ServerlessWP does not make any database updates and uses cached versions of the database. This results in even less costs for this data layer approach.

Pages will be cached only if a user with no cookies for the website requests the content. This is done to avoid caching potentially private content.

The sandboxes use ServerlessWP’s SQLite + S3 database alternative functionality with an auto generated and configured S3 bucket.

The SQLite file used by the sandbox is temporary and may be deleted after a few days/hours depending on load.

All you’ll need is a GitHub account (free) and Vercel account (free). Then click the button below to go through the Vercel project creation flow.

First load times should be approximately 200ms faster and compute time is no longer wasted serving these static resources.

Previously, files had to be served through the handler at least once before CDN caching kicked in through the use of default cache-control headers.

Checkout the code changes for this improvement at GitHub: Vercel support & Netlify support.

ServerlessWP now includes an experimental option to use SQLite and S3 as an alternative to traditional database architectures.

The SQLite integration plugin enables WordPress sites to use a file-based database instead of MySQL/MariaDB.

S3 provides extreme stability and scalability as a data store at tiny cost for low traffic use cases.

ServerlessWP fetches the SQLite database file from S3 before every request is handled. This is a relatively low latency operation if the S3 bucket is in the same region as the serverless deployment. It then writes the database file back to S3 if the data has changed. S3’s conditional write feature prevents one function invocation’s data changes from overwriting that of an other’s if they happen at the same time. In the case of a conflict, the last request is re-attempted.

SQLite + S3 is a great alternative for sites that have a high read-to-write ratio, like blogs, documentation sites, and informational sites. It’s not a great fit for high activity sites like forums or for e-commerce.

To use this feature you’ll need to create an S3 bucket, ideally in the same region as the website (usually defaults to us-east-1 for Vercel and us-east-2 for Netlify). Depending on the S3 or S3 compatible provider’s access methods, you’ll need to create an API key and secret that has access to read and write from the bucket. Then set the following environment variables for your ServerlessWP site to access the S3 bucket: