AI tool comparison
oh-my-codex (OMX) vs Pretty Fish
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
oh-my-codex (OMX)
Oh-my-zsh but for OpenAI Codex CLI — agent teams, hooks, and structured workflows
50%
Panel ship
—
Community
Paid
Entry
oh-my-codex (OMX) is an open-source orchestration layer for OpenAI's Codex CLI, created by Yeachan-Heo. The framing is dead simple: like oh-my-zsh extended the terminal, OMX extends Codex CLI with structured multi-agent workflows, customizable hooks, persistent memory, and a heads-up display (HUD) for monitoring agent activity. It hit 2,867 GitHub stars within days of going trending in early April 2026. OMX's key innovation is team-based execution: rather than one AI agent working through a task linearly, OMX spawns specialist roles — planner, implementer, reviewer, tester — each running in an isolated git worktree to prevent conflicts. The $deep-interview workflow gathers context before starting, $ralplan creates a structured action plan, and $team coordinates the parallel execution. It also adds native Codex hook ownership with PreToolUse/PostToolUse guidance, and ships with Windows and tmux reliability improvements. The practical use case: you have a complex feature to build across multiple files, and you want Codex to plan it properly before touching any code, run specialists in parallel for different modules, and produce a PR-ready result. OMX is that layer. It's explicitly for power users who already live in the terminal and find vanilla Codex too unstructured for serious projects.
Developer Tools
Pretty Fish
Free, beautiful Mermaid diagram editor that works offline
75%
Panel ship
—
Community
Free
Entry
Pretty Fish is a free, open-source Mermaid diagram editor with live preview, 5 built-in themes, multi-page workspaces, and one-click SVG/PNG export. It works offline as a Progressive Web App (PWA) and requires no account, no login, and no installation. It supports all 14+ Mermaid diagram types including flowcharts, sequence diagrams, Gantt charts, entity-relationship diagrams, and Git graphs. The editor includes syntax highlighting, auto-completion, instant error feedback, and a clean split-pane layout. The multi-page workspace lets you manage entire diagram projects in a single session. Export quality is excellent — SVG output is clean and scaling-ready for use in presentations, docs, or design systems. Pretty Fish hit Hacker News front page today with 128 points and has the makings of the go-to Mermaid editor for developers who generate diagrams from AI-assisted documentation workflows. With LLMs increasingly generating Mermaid syntax in their outputs, having a polished renderer and editor matters more than ever.
Reviewer scorecard
“If you use OpenAI Codex CLI daily, OMX is an immediate productivity upgrade. Structured $deep-interview → $ralplan → $team workflows mean Codex actually understands the codebase before writing, and isolated git worktrees for parallel specialists eliminate the merge conflicts that kill multi-agent coding sessions.”
“The official Mermaid live editor is clunky and slow. Pretty Fish loads instantly, works offline, and the multi-page workspace means I can manage all my architecture diagrams in one place. Bookmarking this immediately as my default Mermaid editor.”
“This is a power-user wrapper on Codex CLI, which itself is still early-stage software. You're now debugging two layers of abstraction when things break. The hook system is clever but brittle — and the project is maintained by one developer. Evaluate your risk tolerance before making this a team dependency.”
“It's a genuinely nice editor but it's solving a niche problem — most devs who need Mermaid diagrams already use VS Code extensions or embed them in Notion. And with no backend, there's no collaboration or sharing story, which limits its use in team workflows.”
“Multi-agent coding with isolated worktrees and structured pre-work phases is the right abstraction for complex software. OMX ships this today in a scrappy, hackable form that feels like a preview of where all coding agents are heading in 18 months. The project may get superseded — but the pattern it establishes won't.”
“As AI tools increasingly output Mermaid syntax to explain architectures and flows, the need for a great rendering environment grows. Pretty Fish positions itself at the intersection of AI-generated diagrams and human editing — that's a well-timed niche.”
“Terminal-native and entirely engineer-focused. Zero relevance for creative workflows unless someone builds a GUI on top. Check back if a visual interface emerges.”
“Five beautiful themes and clean SVG exports mean I can finally use Mermaid diagrams in client-facing presentations without them looking like developer scratch notes. This is the Mermaid editor I've always wanted and the zero-friction setup seals it.”
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