finitefield-org/mask-pii

Lightweight, customizable PII masking for emails and phone numbers.

v0.2.0 2026-01-28 07:00 UTC

Requires

• php: >=8.0

Requires (Dev)

• phpunit/phpunit: ^10.0

MIT

• Finite Field, K.K.

• email
• phone
• privacy
• Masking
• pii

README

mask-pii is a lightweight, customizable library for masking Personally Identifiable Information (PII) such as email addresses and phone numbers.

The project provides consistent masking behavior across multiple language implementations, with an emphasis on safety, speed, and easy integration into logging or data processing pipelines.

• 🌐 Official website: https://finitefield.org/en/oss/mask-pii
• 🏢 Developed by: Finite Field, K.K.

Language-specific implementations

• Go: see go/README.md
• D: see d/README.md
• Bash: see bash/README.md
• Carbon: see carbon/README.md
• AWK: see awk/README.md
• Deno: see deno/README.md
• Crystal: see crystal/README.md
• JavaScript: see javascript/README.md
• Elixir: see elixir/README.md
• Groovy: see groovy/README.md
• Haskell: see haskell/README.md
• Hare: see hare/README.md
• Julia: see julia/README.md
• OCaml: see ocaml/README.md
• Lua: see lua/README.md
• Nushell: see nushell/README.md
• PHP: see php/README.md
• PowerShell: see powershell/README.md
• Pony: see pony/README.md
• Python: see python/README.md
• R: see r/README.md
• Red: see red/README.md
• Rust: see rust/README.md
• Ruby: see ruby/README.md
• Swift: see swift/README.md
• Odin: see odin/README.md
• V: see v/README.md
• Fish: see fish/README.md
• Zsh: see zsh/README.md
• Zig: see zig/README.md
• Racket: see racket/README.md
• Common Lisp: see common-lisp/README.md

Core concepts

• Email masking: masks the local part while preserving the domain.
• Phone masking: detects common international formats and masks all digits except the last 4 while keeping separators.
• Customizable: configurable mask character and masking targets.

Notes

Each language implementation documents its own installation and usage details in its respective README.