AI tool comparison
Cal.diy vs Stet
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Productivity
Cal.diy
Cal.com, forked — all enterprise code removed, MIT licensed
50%
Panel ship
—
Community
Paid
Entry
Cal.diy is a community-maintained fork of Cal.com with all enterprise and commercial code stripped out — no Teams, no Organizations, no Insights, no SSO/SAML, and crucially, no license key required. Everything works out of the box under a pure MIT license. The goal is a truly self-hostable, zero-commercial-strings scheduling platform for individuals and small teams who don't need enterprise features but do need full data ownership. The technical stack is unchanged from Cal.com: Next.js, React, tRPC, Prisma ORM, and Tailwind CSS, with support for Google Calendar, Outlook, Daily.co video, email notifications, and standard event type booking flows. The project effectively resolves the "open core trap" by maintaining a clean split: if you want enterprise features, pay Cal.com. If you want a completely free, auditable, no-vendor-lock scheduling system, Cal.diy is the answer. With 41.5k stars (inherited from the Cal.com fork lineage), it has massive visibility. The maintainers are explicit that this is best suited for advanced self-hosters with server admin experience, not a one-click deploy for non-technical users. But for developers who want scheduling infrastructure without SaaS dependencies, it's arguably the cleanest option available.
Productivity
Stet
Local macOS dictation that sounds like you — not like generic AI prose
75%
Panel ship
—
Community
Free
Entry
Stet is an open-source macOS dictation app that transcribes speech locally and then uses AI to clean up the output while actively preserving your personal writing style and tone. The core innovation is a voice model — a lightweight profile that learns from your past writing so the AI corrections don't flatten your voice into generic AI-ese. The result is meant to sound like you dictated it, not like it was passed through a generic LLM. The technical approach combines local Whisper-based transcription (nothing leaves your device during speech-to-text) with an optional AI refinement pass that can use your own API key (BYOK) or a $6.99/month subscription. The open-source release includes the voice profiling code, making it auditable and forkable. It's a direct response to Wispr Flow, which is closed-source and subscription-only. For writers, podcasters, and productivity users who dictate significant amounts of content, the voice preservation angle is genuinely differentiated. The proliferation of AI writing tools has created a recognizable 'AI voice' — flat, over-structured, and devoid of personality — that sophisticated readers are increasingly adept at detecting. Stet's bet is that preserving your actual voice is the most valuable thing an AI writing assistant can do.
Reviewer scorecard
“The open core model has always been a tension with Cal.com — features gated behind enterprise licensing in a supposedly open-source project. Cal.diy resolves that cleanly. The stack is familiar, the MIT license is genuine, and for anyone building a product that needs scheduling infrastructure, this is the right starting point.”
“Open-source, local-first transcription with BYOK is the right architecture. I've been burned by voice tools that upload my audio to servers I can't audit. The voice profile approach for preserving style is technically interesting — I want to see how it handles domain-specific jargon and code-switching between formal and casual registers.”
“This is a maintenance burden in disguise. You're now responsible for keeping a large, complex Next.js codebase patched, secure, and up-to-date with upstream Cal.com changes — changes that may or may not land in the DIY fork on any predictable schedule. For most teams, Cal.com's free tier or Calendly is simply less operational overhead.”
“The 'sounds like you' promise needs a lot of data to actually deliver — your voice profile is only as good as the writing samples it's trained on, and most people don't have a consistent, large corpus of their own writing. For casual dictators, this might just be Whisper with extra steps. Apple's built-in dictation is free and surprisingly good now.”
“Scheduling is increasingly the integration surface AI agents use to take real-world actions — booking meetings, blocking time, managing availability across workflows. Having a fully controllable, self-hosted scheduling layer that AI agents can write to without SaaS rate limits or webhook restrictions is a genuine infrastructure advantage for agentic systems.”
“Voice-first computing is coming back, and the arms race for authentic AI writing assistance is heating up. The distinguishing factor won't be transcription accuracy — everyone has solved that — it will be voice fidelity. Stet is building in the right direction: local processing plus personal style models. Expect this architecture to be standard in two years.”
“For content creators or solopreneurs who just need a Calendly replacement, self-hosting a full Next.js stack is overkill. The UX of the base Cal.com is fine but not exceptional, and the enterprise features you're losing (like organization-level insights) are actually useful for managing content calendar coordination across a team.”
“This is genuinely exciting for writers and content creators. The homogenization of AI-assisted writing is a real aesthetic problem — everything starts sounding like the same LinkedIn post. A tool that actively fights that tendency by learning your specific voice is solving the right problem. Even if the voice model needs work, the direction is exactly right.”
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