head to head · open source
ponytail vs CL4R1T4S
ponytail has 182,779 GitHub stars, 10,094 forks, 270 open issues and last shipped 5 days ago. CL4R1T4S has 51,704 stars, 10,555 forks, 127 open issues and last shipped 1 months ago. ponytail leads on adoption by 254% (182,779 vs 51,704 stars). ponytail is written in JavaScript under MIT; CL4R1T4S is written in various languages under AGPL-3.0. ponytail has attracted 6% as many forks as stars, CL4R1T4S 20%. ponytail was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (prompt-engineering), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| ponytail | CL4R1T4S | |
|---|---|---|
| GitHub stars | ★ 183K | ★ 52K |
| License | MIT | AGPL-3.0 |
| Written in | JavaScript | — |
| Last push | 2026-10-29 | 2026-09-22 |
| Forks | ⑂ 10K | ⑂ 11K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick ponytail if
- You weight community size — 183K stars and counting
- You want the MIT license terms
- Your stack matches JavaScript
- You value the larger contributor base for long-term maintenance
pick CL4R1T4S if
- You want the CL4R1T4S feature set and don't need the biggest community
- You prefer the AGPL-3.0 license terms
- You evaluated both and CL4R1T4S fits your workflow better
About ponytail
Ponytail He says nothing. He writes one line. It works. 54% less code (up to 94%) · 20% cheaper · 27% faster · 100% safe Measured on real Claude Code sessions editing a real open source repo (FastAPI + React), against the same agent with no skill. 54% is the mean across 12 feature tasks (Haiku 4.5, n=4); it reaches 94% where an agent over builds (a date picker) and is near zero where the code is already minimal. ponytail keeps every safety guard while a bare "write one liners" prompt drops one. (The earlier single shot benchmark reported 80 94% as a flat figure; against a fair agentic…
read the full ponytail overview →
About CL4R1T4S
CL4R1T4S AI SYSTEMS TRANSPARENCY AND OBSERVABILITY FOR ALL! Full extracted system prompts, guidelines, and tools from OpenAI, Google, Anthropic, xAI, Perplexity, Cursor, Windsurf, Devin, Manus, Replit, and more – virtually all major AI models + agents! 📌 Why This Exists "In order to trust the output, one must understand the input." AI labs shape how models behave using massive, unseen prompt scaffolds. Because AI is a trusted external intelligence layer for a growing number of humans, these hidden instructions can affect the perceptions and behavior of the public. These prompts define: What AIs can’t say What…
read the full CL4R1T4S overview →
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Frequently asked questions
Is ponytail or CL4R1T4S more popular?
ponytail has 182,779 GitHub stars and CL4R1T4S has 51,704. ponytail has the larger community by that measure.
Are ponytail and CL4R1T4S free?
Both are open source. ponytail is licensed under MIT and CL4R1T4S under AGPL-3.0. Neither carries a licence fee.
What is the difference between ponytail and CL4R1T4S?
ponytail is written in JavaScript and CL4R1T4S in various languages. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, ponytail or CL4R1T4S?
Choose ponytail if you want the larger community (182,779 stars) or its MIT licence terms. Choose CL4R1T4S if its feature set, stack or AGPL-3.0 licence fits better. Both are self-hostable.