Meow (135yshr)

Meow

Paradigm(s)	functional
Designed by	135yshr
Appeared in	2026
Type system	gradual, static
Computational class	Turing complete
Reference implementation	GitHub
Influenced by	Go
File extension(s)	.nyan

Meow is a cat-themed functional programming language created by 135yshr in 2026. Every keyword in the language is a cat-related word: variables are declared with nyan, functions with meow, conditionals with sniff, and printing is done with nya. Error messages are cat-flavored as well, always beginning with Hiss! and ending with , nya~.

Unlike most cat-themed languages, Meow is not an interpreter-only toy: source files (.nyan) are transpiled to Go source code and then compiled to native binaries by the Go toolchain. The language supports gradual static typing, first-class functions, pattern matching, a pipe operator, and a small standard library (file I/O, HTTP, testing). A browser-based playground running a WebAssembly build of the compiler is available on the official website.

Language overview

Meow reserves 25 keywords, all of them cat words:

Keyword	Meaning
nyan	variable declaration
meow	function definition
bring	return a value
sniff / scratch	if / else
purr	loop (range-based)
paw	lambda (anonymous function)
nya	print
lick / picky / curl	map / filter / reduce
peek	pattern match
hiss	raise an error
nab	import a standard library package
yarn / hairball	boolean literals true / false
catnap	nil
kitty	struct definition
breed / collar	type alias / newtype
pose / groom / self	interface / method implementation / instance reference
trill	pure-function modifier

Six type keywords support gradual typing: int, float, string, bool, furball (error value), and litter (list). Annotated code compiles to typed Go; unannotated values fall back to boxed runtime values.

Examples

Hello, world!

nyan name = "Nyantyu"

meow greet(who string) string {
  bring "Hello, " + who + "!"
}

nya(greet(name))

FizzBuzz

meow fizzbuzz(n int) string {
  sniff (n % 15 == 0) {
    bring "FizzBuzz"
  } scratch sniff (n % 3 == 0) {
    bring "Fizz"
  } scratch sniff (n % 5 == 0) {
    bring "Buzz"
  } scratch {
    bring to_string(n)
  }
}

purr i (1..20) {
  nya(fizzbuzz(i))
}

Functional list operations

nyan nums = [1, 2, 3, 4, 5]

nyan doubled = lick(nums, paw(x int) { x * 2 })
nyan evens   = picky(nums, paw(x int) { x % 2 == 0 })
nyan sum     = curl(nums, 0, paw(acc int, x int) { acc + x })

nya(doubled)
nya(evens)
nya(sum)

Fibonacci

meow fib(n int) int {
  sniff (n <= 1) {
    bring n
  }
  bring fib(n - 1) + fib(n - 2)
}

purr i (10) {
  nya(fib(i))
}

Relation to other cat-themed languages

Several unrelated languages on this wiki share the name Meow: Meow (Martsadas), Meow (None1), meow (tommyaweosme), and Meowlang. This Meow is not affiliated with any of them; it is distinguished by transpiling to Go and producing native binaries, rather than being interpreted.

External resources

• Official website
• Online playground (WebAssembly build, runs in the browser)
• Language specification
• Reference implementation on GitHub (written in Go)