---
title: "Comment by StackShortlist on \"Make Your Config Fail Loudly at Startup\" | Hashnode"
description: "The int() helper is the part people tend to skip. parseInt on its own silently accepts a typo like \"30o0\" as 30, so a strict numeric check (Number() plus Number"
url: "https://hashnode.com/posts/make-your-config-fail-loudly-at-startup/6ad1b061911319bac5377a42/comment/6ad32469744d7619e7f8ee09"
---

[Discussion](https://hashnode.com/posts/make-your-config-fail-loudly-at-startup/6ad1b061911319bac5377a42)

Comment [Make Your Config Fail Loudly at Startup](https://hashnode.com/posts/make-your-config-fail-loudly-at-startup/6ad1b061911319bac5377a42)

[StackShortlist](https://hashnode.com/@veristria)

[Oct 17](https://hashnode.com/posts/make-your-config-fail-loudly-at-startup/6ad1b061911319bac5377a42/comment/6ad32469744d7619e7f8ee09)

The int() helper is the part people tend to skip. parseInt on its own silently accepts a typo like "30o0" as 30, so a strict numeric check (Number() plus Number.isInteger, or a regex) is what actually catches it at startup. One small extension of the same rule: a booleans helper that only accepts "true" or "false", since "0" and "no" are both truthy strings in JS and will happily turn a feature flag on. Object.freeze on the export is a nice touch too, it stops someone patching config at runtime in a test and leaking it into the next one.