--- title: Guarantees and Confidence with ReScript | daily.dev description: A developer reflects on why sound type systems matter in practice, using ReScript as the example. The core value highlighted is trust: when code compiles, it... canonical: https://daily.dev/posts/guarantees-and-confidence-with-rescript-z9wljnm5d twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Guarantees and Confidence with ReScript | daily.dev og:description: A developer reflects on why sound type systems matter in practice, using ReScript as the example. The core value highlighted is trust: when code compiles, it... og:url: https://daily.dev/posts/guarantees-and-confidence-with-rescript-z9wljnm5d og:image: https://api.daily.dev/og/posts/Z9WljnM5D.png og:image:alt: Guarantees and Confidence with ReScript og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Guarantees and Confidence with ReScript **[devtools-fm](https://daily.dev/sources/devtoolsfm)** · 1 min read · 0 upvotes · 0 comments ## Summary A developer reflects on why sound type systems matter in practice, using ReScript as the example. The core value highlighted is trust: when code compiles, it works as written, refactors are safe, and the compiler exhaustively checks that all cases are handled by default. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What does exhaustive checking mean in ReScript by default It means the compiler requires every possible case or branch in pattern matching to be handled, rather than allowing silent gaps. This is enabled by default rather than needing opt-in configuration, so unhandled cases become compile errors instead of runtime surprises, giving developers confidence that logic branches are fully covered before shipping. _Developers weighing exhaustive pattern matching across languages can track ReScript discussions on daily.dev._ ## Similar posts on daily.dev - [The Compiler Is Your Best Friend, Stop Lying to It](https://daily.dev/posts/the-compiler-is-your-best-friend-stop-lying-to-it-li48byr93) · Hacker News · 11 upvotes · 3 comments - [ReScript 12.0 Released with New Build System](https://daily.dev/posts/rescript-12-0-released-with-new-build-system-7fyk8mhqs) · InfoQ · 0 upvotes · 0 comments --- Tags: [#type-systems](https://daily.dev/tags/type-systems) [View this post on daily.dev](https://daily.dev/posts/guarantees-and-confidence-with-rescript-z9wljnm5d) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Guarantees and Confidence with ReScript","url":"https://daily.dev/posts/guarantees-and-confidence-with-rescript-z9wljnm5d","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/guarantees-and-confidence-with-rescript-z9wljnm5d"},"datePublished":"2026-10-03T18:43:38.938Z","dateModified":"2026-10-03T18:43:54.662Z","description":"A developer reflects on why sound type systems matter in practice, using ReScript as the example. 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