mustache

Mustache.js delivers on its promise of logic-less templating with an incredibly shallow learning curve. The API is minimal - essentially just `Mustache.render(template, data)` - and you'll be productive within minutes. The official mustache spec means templates are portable across languages, which is valuable if you're working in polyglot environments. Documentation covers all the basics with clear examples of sections, partials, and lambdas.

The real-world experience is mostly smooth for straightforward use cases. Passing data objects and iterating over arrays just works. However, debugging is where things get painful. Error messages are cryptic or non-existent when templates fail silently. Mismatched tags or undefined variables often result in empty output with no indication of what went wrong. You'll find yourself adding console.logs to your data objects constantly.

Community support is decent but scattered. Stack Overflow has answers for common issues, though the package hasn't changed much in years so some advice feels dated. The GitHub repo is still maintained but don't expect rapid responses. For simple templating needs where you value simplicity over features, it's a solid choice.

Mustache.js does exactly what it promises: logic-less templating with a minimal API. The core `Mustache.render(template, data)` is dead simple and works reliably. However, the developer experience feels dated compared to modern alternatives. TypeScript support is minimal - you get basic type definitions, but no generics for template data, so you lose type safety on your context objects. The IDE can't validate that your template variables match your data structure.

Error messages are frustratingly vague. Typos in template variables silently render as empty strings rather than throwing errors, making debugging tedious. There's no built-in way to enable strict mode or get warnings about undefined variables. The documentation is bare-bones - it covers syntax but lacks practical examples for common patterns like nested partials or custom delimiters.

The library hasn't seen updates since 2021, and it shows. No ESM exports by default, limited tooling integrations, and the caching mechanism requires manual management. For simple use cases it's fine, but you'll quickly miss features like proper error boundaries, template validation, and better TypeScript integration that newer libraries provide.

Mustache.js is refreshingly straightforward to use. The API is minimal - basically just `Mustache.render(template, data)` - and you can be productive within minutes. The logic-less philosophy means templates are clean and the separation between logic and presentation is enforced by design. Documentation is clear with plenty of examples covering sections, partials, and lambdas. The official mustache spec examples translate directly to JavaScript, which makes learning easier.

Error messages could be better, though. Silent failures are common - if a variable doesn't exist, you get an empty string rather than a warning. Debugging template issues often means adding console.logs to your data object. Partials work well but require manual registration, which feels a bit tedious compared to modern frameworks. The package hasn't been updated since 2021, but that's partly because the spec is stable and the implementation is mature.

Day-to-day usage is smooth for straightforward templating tasks. The predictable behavior and lack of magic make it easy to reason about what your templates will output. It's particularly good for email templates, simple reports, or any scenario where you want strict logic-presentation separation.