January 10, 2026
Fun or Cursed? You Decide
MetaFun: Compile Haskell-like code to C++ template metaprograms
Haskell‑ish code turned into C++ compile‑time magic — devs split between awe and horror
TLDR: MetaFun lets you write Haskell‑style code that turns into C++ templates running at compile time, but it’s a rough demo with missing features. Commenters are split between calling it genius art and cursed chaos, joking about compile times and error messages while debating if it’s educational or pointless.
MetaFun just dropped a curveball: write in a Haskell‑like language called Kiff and watch it transform into C++ template spells that run at compile time. The creator admits it’s a week‑in‑bed, proof‑of‑concept toy with missing basics like lambdas (anonymous functions) and currying, but the internet did not care—because the drama was instant. One camp is calling it art, another is calling it a war crime, and everyone’s posting memes. You can grab it on GitHub, but bring popcorn.
Fans are giddy over the sheer audacity. “It solves a 9‑digit puzzle while compiling? Inject it in my veins,” one commenter cheered, loving the retro callback to the days when C++ templates were used for everything. The skeptics, though, are having a field day: “No lambdas in ‘Keep It Fun & Functional’ is the best joke of 2026,” sniped another. Critics warn of nightmare compile times and error messages “longer than a CVS receipt,” while pragmatists say modern C++ already has easier tools and ask, “Why not just use Haskell?” The hottest debate: Is this educational brilliance or cursed cosplay? Meanwhile, the meme machine is on fire—knee‑injury origin story jokes, “template necromancy” gifs, and mock obituaries for developer sanity. Love it or loathe it, MetaFun has everyone extremely online and extremely loud.
Key Points
- •MetaFun compiles Kiff (a Haskell-like language) into C++ template metaprograms for compile-time execution.
- •Kiff supports algebraic data types, declared types, and parametric polymorphism; some listed features (type synonyms, λ syntax) are not yet supported.
- •Kiff primitives map to C++ types and operators, including Bool, Int, logical operations, integer comparisons, and arithmetic.
- •Generated C++ consists of template structs and specializations that emulate functional recursion and pattern matching, boxing primitive values.
- •MetaFun is a proof-of-concept with limitations: no currying, no lambda expressions, incomplete type synonym support, and zero optimization; includes a nine-digit backtracking example inspired by Károly Lőrentey.