# RcppSimdJson 0.1.17 adds C++17 fallback for better compatibility

> **Key takeaway:** RcppSimdJson 0.1.17 introduces a compilation fallback to C++17 to resolve build failures on macOS x86_64 environments lacking full C++20 support.

**Published:** 2026-10-16T19:56:00+00:00 
**Source:** Planet Debian (Developer Blogs) 
**Category:** distro-planet 
**Canonical URL:** https://fosswire.org/news/rcppsimdjson-0117-adds-c17-fallback-for-better-compatibility.html 

## Summary
The RcppSimdJson package, which provides high-performance JSON parsing for R using the simdjson library, has released version 0.1.17 to CRAN. This update addresses compilation issues on macOS x86_64 where C++20 features like ranges and concepts were unavailable. The release also includes an upgrade to simdjson version 5.0.5.

## Technical changes in RcppSimdJson 0.1.17
- Implements a **C++20 feature test** during compilation; if the test fails, the build automatically falls back to **C++17**.
- Upgrades the underlying **simdjson** library to version **5.0.5**.
- Improves the handling of **disabling pragmas** to assist with CRAN compliance checks.

## Why it matters
This update ensures that users on older or partially compliant macOS hardware can still utilize the high-speed SIMD-accelerated JSON parsing provided by the package.