# Theme not Found Locally (MissingDependencyException / Gem::MissingSpecError)

**URL:** <https://talk.jekyllrb.com/t/theme-not-found-locally-missingdependencyexception-gem-missingspecerror/10312>\
**Category:** Help\
**Created:** [March 13, 2026, 10:12pm UTC](https://talk.jekyllrb.com/t/theme-not-found-locally-missingdependencyexception-gem-missingspecerror/10312 "2026-03-13T22:12:01Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ahutnick](https://avatars.discourse-cdn.com/v4/letter/a/eada6e/32.png) [@ahutnick](https://talk.jekyllrb.com/u/ahutnick)\
**Post date:** [March 13, 2026, 10:12pm UTC](https://talk.jekyllrb.com/t/theme-not-found-locally-missingdependencyexception-gem-missingspecerror/10312/1 "2026-03-13T22:12:01Z")

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Hello,

First time developing a custom Jekyll theme. Uploaded the gem to rubygems successfully, installed the gem successfully, and set up the theme in the config file. However, when I run bundle exec jekyll serve, I get this error:

The digitalhealthhumanities-toolkit-theme theme could not be found. (Jekyll::Errors::MissingDependencyException)

Later, I get a Gem::MissingSpecError, and lo and behold, the spec hasn’t been installed. I’ve tried updating the gemspec to match more closely with minima, but to no avail.

I checked both my vendors/cache and vendors/cache/ruby/[version]/gems folders, and the gems are present. I’ve seen people report this error, but no solutions. Can anyone help?

theme: [GitHub - DigitalHealthHumanities/toolkittheme · GitHub](https://github.com/DigitalHealthHumanities/toolkittheme/tree/main)

Website Gemfile:

`source ‘[https://rubygems.org](https://rubygems.org)’

gem ‘github-pages’

gem ‘DigitalHealthHumanities-toolkit-theme’, ‘~\> 0.1.6’`

Website: config.yml:

`theme: DigitalHealthHumanities-toolkit-theme`

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<div class="post-metadata">

**Author:** ![ahutnick](https://avatars.discourse-cdn.com/v4/letter/a/eada6e/32.png) [@ahutnick](https://talk.jekyllrb.com/u/ahutnick)\
**Post date:** [March 14, 2026, 11:34pm UTC](https://talk.jekyllrb.com/t/theme-not-found-locally-missingdependencyexception-gem-missingspecerror/10312/2 "2026-03-14T23:34:17Z")

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Figured it out - for anyone else just starting out with creating Jekyll themes / Ruby gems, don’t use capital letters. Jekyll will get confused.