---
title: MARKLESS_SERVER_DERIVE_UNREACHABLE
description: "This computed value cannot be worked out on the server: a Markless compiler error."
sidebar: { hidden: true }
search: { keywords: ["SERVER_DERIVE_UNREACHABLE","server derive unreachable","markless error"] }
pagination: false
---

**Error** from the compiler, while it builds your `.tsrx` files.

## What happened

Markless prints the message, the reason, and a suggestion:

```text
MARKLESS_SERVER_DERIVE_UNREACHABLE: <cause> Anything reading it would render as if the value were missing.
Server rendering works each computed value out once and puts it in the state the page is served with. A value it cannot work out reads as undefined, and every attribute and piece of text built from it silently disappears from the HTML.
cycle
https://markless.dev/errors/MARKLESS_SERVER_DERIVE_UNREACHABLE
```

Words in angle brackets change from case to case.

## How to fix it

Start with the suggestion in the message above.

This page has no guide yet. [Help write it](/contributing/improve-these-docs).

## Where it comes from

`@markless/compiler` raises this code. Source:

- [packages/compiler/src/passes/public-render/diagnostics.ts](https://github.com/compiled-run/markless/blob/main/packages/compiler/src/passes/public-render/diagnostics.ts)

Read [how to read a Markless error](/tooling/diagnostics), or go back to [all error codes](/errors).