AI tool comparison
Cal.diy vs Mike
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
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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
Mike
Open-source legal AI that reads docs, cites verbatim, and drafts contracts
75%
Panel ship
—
Community
Free
Entry
Mike is an open-source legal AI platform built as a direct alternative to Harvey and Legora — without the vendor lock-in or per-seat pricing. It connects to Claude or Gemini via your own API keys and gives solo practitioners and small firms the same document review, contract drafting, and workflow automation capabilities that enterprise legal tools charge thousands for. The platform organizes work into matter-scoped Projects — persistent workspaces where documents stay contextually linked across sessions. Its Tabular Review feature extracts structured data from multiple documents into a spreadsheet view, with every cell backed by a verbatim citation you can click to verify. Workflows layer on top for repeatable tasks like credit agreement summaries and change-of-control reviews. Mike is built by Will Chen and is self-hostable or available as a cloud product. The fundamental pricing model is radical: you pay only your Claude or Gemini API costs. No license fees, no per-seat pricing. For small firms doing high-volume document review, the economics are dramatically better than any SaaS alternative at $500–$2,000/user/month.
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.”
“Self-hosted legal AI that runs on your own Claude or Gemini API key is genuinely clever — the pricing model alone makes this worth exploring. The codebase is clean and the tabular citation view is the kind of UX detail that shows someone actually thought about the legal workflow. Deploy this for any firm that's been priced out of Harvey.”
“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.”
“Solo dev projects in legal tech carry serious liability risk — if the model hallucinates a clause or misses a citation, the consequences aren't a bad tweet, they're malpractice exposure. Until this has real-world usage data from actual attorneys and independent security audits, enterprise law firms should stay cautious. Also, Claude Sonnet or Gemini Flash are not the same as GPT-5.5 fine-tuned on case law.”
“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.”
“Open-source legal AI is the first credible wedge against the Harvey monopoly on AI-native law. When every solo practitioner and boutique firm can deploy their own matter-scoped AI workspace for free, the power dynamic in legal tech shifts permanently. Mike is the kind of project that looks small today and reshapes an industry in five 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.”
“The tabular review UI is genuinely beautiful for a developer-built open source project — it solves the 'show your work' problem that makes lawyers distrust AI outputs. If the UX holds up under real document loads, this is the design template for AI tools in trust-sensitive industries.”
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