---
title: Eval Fallback Mode
description: "## What it is By default, GOCSM writes PHP snippets to disk and loads them via `require_once`. On some managed hosting environments, the web server process does not have write access to `wp-content/uploads/`. Eval fallback mode allows GOCSM to function…"
url: "https://brightleafdigital.io/docs/eval-fallback-mode/"
updated: "2026-10-20"
category: GravityOps Code Snippet Manager / Advanced
---

# Eval Fallback Mode

## What it is

By default, GOCSM writes PHP snippets to disk and loads them via `require_once`. On some managed hosting environments, the web server process does not have write access to `wp-content/uploads/`. Eval fallback mode allows GOCSM to function in those environments by executing snippet code via `eval()` instead.

## Modes

| Mode | Behaviour |
| --- | --- |
| **Off** (default) | File generation only. If the filesystem is not writable, activation fails with an error. |
| **Auto** | Try file generation first. Fall back to eval if the write fails or the generated file is missing at runtime. |
| **Always** | Never write PHP snippet files. Every PHP snippet runs through eval, including any snippet that still has a file from an earlier mode. Useful when a host or security scanner rejects PHP files in `wp-content/uploads/`. JavaScript and CSS snippets are still written as files. |

Configure the mode under **Settings > Eval fallback mode**.

## Config injection in eval mode

Config values are still injected before evaluation. GOCSM replaces config block values with your stored values, strips the leading `<?php` tag, then passes the result to `eval()`.

## Limitations of eval mode

- No OPcache benefit — the code is recompiled on every request.
- Stack traces show `eval()'d code` instead of a real file path, which makes debugging harder.
- Some security hardening tools block `eval()` outright.

Eval fallback is provided for compatibility only. File-based execution is strongly preferred.

Active PHP snippets that run through eval show an `(eval)` badge in the snippets list: every active PHP snippet under **Always**, and under **Auto** any whose generated file is missing. Under **Auto**, an admin notice also counts the snippets that have fallen back to eval, since that usually means the filesystem stopped being writable.