How does evalcache compare to direnv for shell optimization?

evalcache caches static initialization commands to speed up zsh startup, while direnv loads environment variables dynamically per directory. evalcache is better for fixed command outputs, but direnv handles changing environments more flexibly.

How to install evalcache with Oh-My-Zsh?

Clone the repository into the custom plugins directory and add 'evalcache' to your plugin list in .zshrc. The README provides detailed steps for this, ensuring seamless integration with Oh-My-Zsh.

Does evalcache work with bash?

No, evalcache is specifically designed for zsh and relies on zsh features. It won't function in bash or other shells, limiting its use to zsh users only.

What happens if the cached output becomes outdated?

You need to manually clear the cache using `_evalcache_clear` to regenerate it. The plugin doesn't auto-invalidate caches, so stale data can persist until you intervene.

Can evalcache cache multiple commands from different tools?

Yes, you can use `_evalcache` for each initialization command separately. However, each command is cached independently, and performance gains depend on the static nature of each output.

Is evalcache safe for production environments?

It can be used, but exercise caution due to caching. Ensure initialization commands are truly static and manage cache invalization carefully during updates to avoid configuration issues.

Open-Awesome

evalcache

MITShellv1.0.3

A zsh plugin that caches the output of binary initialization commands to significantly reduce shell startup time.

GitHub

264 stars15 forks0 contributors

What is evalcache?

evalcache is a zsh plugin that caches the output of binary initialization commands to reduce shell startup time. It works by replacing `eval` commands with `_evalcache`, storing the static output in a file for future use, which eliminates the overhead of repeatedly executing the same initialization scripts.

Target Audience

Developers using zsh who rely on tools like rbenv, hub, or scmpuff and want to optimize their shell startup performance, especially those who frequently open new terminal tabs or sessions.

Value Proposition

It provides a simple, non-intrusive way to shave milliseconds off shell startup by caching static initialization output, with minimal configuration and graceful fallback behavior if tools are removed.

Overview

:hatching_chick: zsh plugin to cache eval loads to improve shell startup time

Use Cases

Best For

Reducing zsh startup time when using multiple shell wrapper tools
Optimizing terminal performance for developers who open many shell sessions
Caching static initialization commands from tools like rbenv or hub
Improving productivity by speeding up shell environment loading

Not Ideal For

Shell environments using bash or other non-zsh shells
Dynamic initialization commands where output changes frequently
Users with minimal shell startup overhead or few initialization tools
Systems requiring real-time execution for security or compliance

Pros & Cons

Pros

Significant Speed Gains

Benchmarks in the README show up to 88% reduction in initialization time for tools like rbenv, making subsequent shell startups much faster.

Graceful Degradation

If a tool is uninstalled, evalcache automatically becomes a no-op, preventing errors and ensuring compatibility without manual intervention.

Easy Cache Management

Includes a convenience function `_evalcache_clear` to manually clear cached files, as documented, simplifying updates when needed.

Minimal Configuration

Works out of the box with default settings, and environment variables like ZSH_EVALCACHE_DIR allow customization without complex setup.

Cons

Static Output Limitation

Only caches static initialization commands; dynamic or time-sensitive outputs may become stale, requiring manual cache clearing and potentially causing issues.

Tool Dependency

Primarily optimized for specific tools like rbenv, hub, and scmpuff; it offers less benefit for other initialization patterns or custom scripts.

Manual Cache Invalidation

Users must remember to clear caches after tool updates, as there's no automatic invalidation, which can lead to outdated configurations if overlooked.

Frequently Asked Questions

Related Projects

zoxide

A smarter cd command. Supports all major shells.

Stars40,266

Forks933

Last commit18 hours ago

zsh-autosuggestions

Fish-like autosuggestions for zsh

Stars36,151

Forks1,940

Last commit1 year ago

zsh-syntax-highlighting

Fish shell like syntax highlighting for Zsh.

Stars23,050

Forks1,374

Last commit15 days ago

autojump

A cd command that learns - easily navigate directories from the command line

Stars16,966

Forks708