I’ve been working on a shard that is an interesting experiment. big_number is a pure Crystal implementation of arbitrary-precision BigInt, BigRational, BigFloat, and BigDecimal with No C dependencies just Crystal. no libgmp no Cross-compilation no static libgmp no alternate license I wanted to se…

Looks awesome! Matching libgmp performance wouldn’t be easy though - looks like it use assembly routines for all supported platforms. But pure Crystal implementation is great for things like WASM.

yeah I dont think a project like this would ever be able to achieve the same performance. So it could not be a goal of this project. Right now the goal of this project is to see if this is possible and if it has any use case. This is experimental in the true sense of the word. It is an experiment…

[image] Jack Thorne: I dont think a project like this would ever be able to achieve the same performance. It might be able to. Crystal supports inline assembly, so this project would just need CPU-specific implementations of some operations with a generic fallback. For example, AVX512-capable…

That is encouraging. I am enjoying exploring this space so I am going to continue to work on this. I really want to see what people use this for in Crystal and what their use cases are. When I search github I get mostly advent of code, experimental languages, and crypto. I imagine if I could sea…

There ain’t that many big number libraries, and an AI might just port code from GMP or another lib into Crystal without your knowledge. I’d be very wary of licensing issues (GMP is LGPL for example). Starting a big number shard in super interesting, it would be awful to get into licensing issues.

This is great! “big“ appears in unexpected places sometimes; I remember writing an application that I wanted to statically link just to find out that it had a dependency on GMP because it used the “jwt“ shard. Having a pure crystal implementation with a permissive license is awesome; even if the per…

I really hope this can get used, delete libgmp is a BIG improvement.

[image] Jack Thorne: I really want to see what people use this for in Crystal and what their use cases are. I probably never use it, but because it is a dependency for Crystal application, I probably can’t build a static binary successful because libgmp.

Alpine has gmp-static so that should not be a problem

Big_number — Pure Crystal GMP replacement

wontruefree March 13, 2026, 5:05am 8

So this is actually great to hear. I am curious what pain points and use cases there are around GMP.

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Big_number — Pure Crystal GMP replacement

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