{ ... }: pkgs: stdenv: let inherit (lib) optionalAttrs optionals toList; inherit (pkgs) lib; inherit (stdenv) targetPlatform; in pkgs.addAttrsToDerivation (prevAttrs: let overrideAlloc = prevAttrs.overrideAlloc or true; inputs = optionals overrideAlloc [ pkgs.mimalloc ]; cflagsE = [ "-flto" ]; cflagsC = [ "-pipe" ]; cflagsL = [ "-fuse-ld=lld" ]; ldflags = [ "-O2" "--hash-style=gnu" "--icf=safe" "--lto-O2" ] ++ optionals overrideAlloc [ "-lmimalloc" ]; rustflags = [ "-C" "opt-level=2" "-C" "linker-flavor=ld.lld" "-C" "lto" "-C" "linker-plugin-lto" ] ++ optionals (targetPlatform.isx86_64 && targetPlatform ? gcc.arch) [ "-C" "target-cpu=${targetPlatform.gcc.arch}" ] ++ (map (flag: [ "-C" "link-arg=${flag}" ]) ldflags |> lib.flatten); goflags = [ "-ldflags=-linkmode=external" ]; in { buildInputs = prevAttrs.buildInputs or [ ] ++ inputs; env = prevAttrs.env or { } // optionalAttrs (!prevAttrs ? CFLAGS) { CFLAGS = toList prevAttrs.CFLAGS or [ ] ++ cflagsE |> toString; } // optionalAttrs (!prevAttrs ? NIX_CFLAGS_COMPILE) { NIX_CFLAGS_COMPILE = toList prevAttrs.env.NIX_CFLAGS_COMPILE or [ ] ++ cflagsC |> toString; } // optionalAttrs (!prevAttrs ? NIX_CFLAGS_LINK) { NIX_CFLAGS_LINK = toList prevAttrs.env.NIX_CFLAGS_LINK or [ ] ++ cflagsL |> toString; } // optionalAttrs (prevAttrs ? env.NIX_LDFLAGS) { NIX_LDFLAGS = toList prevAttrs.NIX_LDFLAGS or [ ] ++ ldflags |> toString; }; NIX_RUSTFLAGS = prevAttrs.NIX_RUSTFLAGS or [ ] ++ rustflags; GOFLAGS = prevAttrs.GOFLAGS or [ ] ++ goflags; } // optionalAttrs (prevAttrs ? CFLAGS) { CFLAGS = toList prevAttrs.CFLAGS or [ ] ++ cflagsE; } // optionalAttrs (prevAttrs ? NIX_CFLAGS_COMPILE) { NIX_CFLAGS_COMPILE = toList prevAttrs.NIX_CFLAGS_COMPILE or [ ] ++ cflagsC; } // optionalAttrs (prevAttrs ? NIX_CFLAGS_LINK) { NIX_CFLAGS_LINK = toList prevAttrs.NIX_CFLAGS_LINK or [ ] ++ cflagsL; } // optionalAttrs (!prevAttrs ? env.NIX_LDFLAGS) { NIX_LDFLAGS = toList prevAttrs.NIX_LDFLAGS or [ ] ++ ldflags; }) stdenv