• ABI change: 64-bit target values, more room for expansion
• Add CompressBlocksNot, CompressNot, Lt128Upper, Min/Max128Upper, TruncateTo
• Add HWY_SVE2_128 target
• Sort speedups especially for 128-bit
• Documentation clarifications
• Faster NEON CountTrue/FindFirstTrue/AllFalse/AllTrue
• Improved SVE codegen
• Fix u16x8 ConcatEven/Odd, SSSE3 i64 Lt
• MSVC 2017 workarounds
• Support for runtime dispatch on Arm/GCC/Linux

The 1.0 release signals an increased focus on backwards compatibility. Applications using documented functionality will remain compatible with future updates that have the same major version number.