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Proof-of-Work · Invisible

ALTCHA

Daniel Regeci / community · Self-hosted (any) · since 2023-09

MIT-licensed proof-of-work widget you can drop in and forget. No external servers required, no signups, no tracking. The privacy-first community choice that has been popping up everywhere since late 2024.

Open sourceSelf-hostableFree
Free quota
Unlimited (self-host) or hosted plan
Pricing
Self-hosted free, ALTCHA Pro from $9/mo for hosted

// pros

  • + No external service required
  • + Trivially auditable code
  • + Works without JavaScript fallback for some setups

// cons

  • No central threat data, so harder bots can solve PoW too
  • No managed dashboard or analytics
  • Smaller community than commercial alternatives

// highlights

  • MIT licensed, fully open source
  • Self-host with zero dependencies
  • No cookies, no fingerprinting
  • Native HTML form input
  • Server libraries in 8+ languages

// specs

Pricing
free
Open source
Yes
Self-host
Yes
Audited
Not yet
HQ
Self-hosted (any)
Since
2023-09
License
MIT
Frameworks
9 supported