Cryptography is the wrong motivation for this (unless you want a fast algorithm to break some encryption). In cryptography the main goal is not best performance, but predictable performance to avoid timing attacks. Sometimes you don’t want to treat special cases special because it would reveal something about your cipher.

> On Jan 13, 2026, at 2:34 PM, Hans Åberg via Std-Proposals <std-proposals_at_[hidden]> wrote:
>
> There might be support for modular integers int_mod<m> ≔ ℤ/mℤ for a modulus m that fits into a fixed-sized word, say 4096 bits for use in cryptology, m ≤ 2⁴⁰⁹⁶. With recursive templates, like those I have written, for fixed-size unsigned integral types up to uint4096_t, it should not be difficult to implement.
>
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