Herb on Rails
It finds the tags, evaluates the Ruby inside them, and concatenates everything else as plain text. Broken markup can now fail while the template compiles, instead of reaching a browser.
Useful takeaways from this story.
It finds the tags, evaluates the Ruby inside them, and concatenates everything else as plain text.
Broken markup can now fail while the template compiles, instead of reaching a browser.
you will learn what Herb is, how to audit your own views with it today, what it can fix for you, what it cannot, and…
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The useful part
It finds the tags, evaluates the Ruby inside them, and concatenates everything else as plain text. Broken markup can now fail while the template compiles, instead of reaching a browser. you will learn what Herb is, how to audit your own views with it today, what it can fix for you, what it cannot, and…
What to take from it
Whether the result is valid markup has never been its problem.
Details worth keeping
Originally appeared on The Rails Tech Debt Blog. ERB does not know that it is generating HTML. On August 25, 2026, the Ruby on Rails core team merged Add Herb as an HTML-aware ERB implementation, which brings in Herb, an ERB implementation that parses HTML and ERB into a single syntax tree and uses Prism for the Ruby inside the tags.
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