Common Pitfalls #

Same Input and Output Dir with HTML Templates #

If you’re using --formats=html and run eleventy more than once, it’ll try to process your output files too.

$ eleventy --input=. --output=. --formats=md,html
Writing ./README/index.html from ./README.md

$ eleventy --input=. --output=. --formats=md,html
Writing ./README/index.html from ./README.md
Writing ./README/index-o.html from ./README/index.html

If you’re going to use --formats=html, it’s probably best not using the same input and output directories.

Moreover, you may notice in the above output that the second template wrote to index-o.html. When the input and output directories are the same and the source template is named index.html, we add an -o suffix to avoid overwriting itself. This is a special case that only applies to index.html filenames. You can customize the -o suffix with the htmlOutputSuffix configuration option.

File Creation Dates reset on Continuous Integration server #

Be careful relying on the default date associated with a piece of content. By default Eleventy uses file creation dates, which works fine if you run Eleventy locally but may reset in some conditions if you run Eleventy on a Continuous Integration server. Work around this by using explicit date assignments, either in your front matter or your content’s file name. Read more at Content Dates.

Dates off by One Day? #

Many date formats in Eleventy (when set in your content‘s filename as YYYY-MM-DD-myfile.md or in your front matter as date: YYYY-MM-DD) assume midnight in UTC. When displaying your dates, make sure you’re using the UTC time and not your own local time zone, which may be the default.

Example #

---
date: 2018-01-01
---

{{ page.date }} will display a local time zone date.
Mon Jan 01 2018 00:00:00 GMT+0000 (Coordinated Universal Time)

{{ page.date.toString() }} will display a local time zone date.
Mon Jan 01 2018 00:00:00 GMT+0000 (Coordinated Universal Time)

{{ page.date.toUTCString() }} will display a UTC time zone date.
Mon, 01 Jan 2018 00:00:00 GMT

Read more at Content Dates.

Quoted Include Paths and Liquid Templates #

Read more at Liquid Templates.