Life & fun · alternatives · 2026

24 alternatives to C++ runtime/compile-time detection in constexpr functions

An approach for runtime detection inside a constexpr function - SaadAhmad/in_constexpr

This is a C++ library that enables detection of whether code is executing at runtime or compile-time within constexpr functions. It allows developers to write functions that behave differently depending on the… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. C++ runtime/compile-time detection in constexpr functions launched in 2017; newer entries below may have overtaken it.

1. 1
   Compile-time HTML parsing in C++14▲175

   A C++ HTML template engine that uses compile time HTML parsing - rep-movsd/see-phit

   2017 · github.com · its alternatives →

2. 2CA
   Computation at Compile-Time now free online▲57

   2017 · billsix.github.io · its alternatives →

3. 3
   Cronexpr, a Rust library to parse and iter crontab expression▲160

   `cronexpr` is a library to parse and drive the crontab expression.

   2024 · docs.rs · its alternatives →

4. 4
   LazyCode – C++14 composable, lazily evaluated map, filter, fold▲66

   C++14: bringing in those expressions that you wish you had, Lazily evaluated, compossible generators, maps, filters, ranges and more... - GitHub - SaadAttieh/lazyCode: C++14: bringing in those expressions that you wish you had, Lazily evaluated, compossible generators, maps, filters, ranges and more

   2018 · github.com · its alternatives →

5. 5
   beLow▲176

   Inline insights with C/C++ that shows CPU, memory, energy

   Dec 2025 · wedolow.com · its alternatives →

6. 6
   CXXStateTree – A modern C++ library for hierarchical state machines▲48

   Hi HN! I've built [CXXStateTree](https://github.com/ZigRazor/CXXStateTree), a modern C++ header-only library to create hierarchical state machines with clean, intuitive APIs. It supports: - Deeply nested states - Entry/exit handlers - State transitions with guards and actions - Asynchronous transitions with `co_await` (C++20 coroutines) - Optional runtime type identification for flexibility It's ideal for complex control logic, embedded systems, games, robotics, and anywhere you'd use a finite state machine. I’d love feedback, use cases, or contributions from the…

   2025 · github.com · its alternatives →

7. 7CJ
   Constexpr.js▲10

   2021 · fctorial.github.io · its alternatives →

8. 8
   Kent Dybvig's Scheme Machine in 400 Lines of C (Heap-Memory Model)▲226

   Heap based scheme machine. GitHub Gist: instantly share code, notes, and snippets.

   2025 · gist.github.com · its alternatives →

9. 9
   Typed-arrow – compile‑time Arrow schemas for Rust▲48

   Hi community, we just released https://github.com/tonbo-io/typed-arrow. When working with arrow-rs, we noticed that schemas are declared at runtime. This often leads to runtime errors and makes development less safe. typed-arrow takes a different approach: - Schemas are declared at compile time with Rust’s type system. - This eliminates runtime schema errors. - And introduces no runtime overhead — everything is checked and generated by the compiler. If you’ve run into Arrow runtime schema issues, and your schema is stable (not defined or switched at runtime), this project…

   2025 · github.com · its alternatives →

10. 10
    Run – a CLI universal code runner I built while learning Rust▲96

    Hi HN — I’m learning Rust and decided to build a universal CLI for running code in many languages. The tool, Run, aims to be a single, minimal dependency utility for: running one-off snippets (from CLI flags), running files, reading and executing piped stdin, and providing language-specific REPLs that you can switch between interactively. I designed it to support both interpreted languages (Python, JS, Ruby, etc.) and compiled languages (Rust, Go, C/C++). It detects languages from flags or file extensions, can compile temporary files for compiled languages, and exposes a unified REPL…

    2025 · github.com · its alternatives →

11. 11
    A dbg(...) macro for C++▲162

    A dbg(…) macro for C++. Contribute to sharkdp/dbg-macro development by creating an account on GitHub.

    2019 · github.com · its alternatives →

12. 12
    Error return traces for Go, inspired by Zig▲133

    An alternative to stack traces for your Go errors. Contribute to bracesdev/errtrace development by creating an account on GitHub.

    2023 · github.com · its alternatives →

13. 13AI
    Anyone interested in a tool helps to explore C++ ASTs▲49

    I built this software to help users who need to do static code analysis for C/C++ codebase. This can help you to explore the ASTs interactively. It can replace the Clang ast dump completely and also you can search the code/ASTs in a structual way. For example you can search a function which matches specific name or number of paremeters.

    May 2026 · uvic-aurora.github.io · its alternatives →

14. 14
    A Fast, Malloc-Free C++14 Json Parser and Encoder▲98

    Meta programming utilities for C++14. Merged in matt-42/lithium - matt-42/iod

    2014 · github.com · its alternatives →

15. 15
    Compile for Arm at native speeds in an emulated system▲63

    Runs AWS graviton2 images on intel, with native-speed compile times - valkmit/aws-graviton2-on-intel

    2021 · github.com · its alternatives →

16. 16
    I built a tensor library from scratch in C++/CUDA▲119

    Hi HN, Over the past few months, I've been building `dsc`, a tensor library from scratch in C++/CUDA. My main focus has been on getting the basics right, prioritizing a clean API, simplicity, and clear observability for running small LLMs locally. The key features are: - C++ core with CUDA support written from scratch. - A familiar, PyTorch-like Python API. - Runs real models: it's complete enough to load a model like Qwen from HuggingFace and run inference on both CUDA and CPU with a single line change[1]. - Simple, built-in observability for both Python and C++. Next on the roadmap is…

    2025 · github.com · its alternatives →

17. 17
    Single-Header Profiler for C++17▲68

    Morning HN. I often found myself wondering "how much does this code segment take in terms of total runtime" and it's often quite annoying to figure out with optimizations enabled, especially when working on something new or testing someone else's implementation without the proper tooling set up. Wanted to have a single include lib that would allow us to write something like: ``` PROFILE("Loop 1") for (...) // some work ``` and have the next expression automatically record time & dump results to a table. Wrote a few macros to do exactly that a few months back, but they were…

    2025 · github.com · its alternatives →

18. 18
    Using C++23 <stacktrace> to get proper crash logs in C++ programs▲103

    A simple way to output stack traces when a program crashes in C++, using the new C++23 <stacktrace> header - TylerGlaiel/Crashlogs

    2023 · github.com · its alternatives →

19. 19
    Goroutine-analyzer: A visual goroutine stack dump debugging tool▲73

    Helps analyze goroutines. Inspired by TDA for Java and goroutine-inspect for golang. - openziti/goroutine-analyzer

    2022 · github.com · its alternatives →

20. 20
    A weekend replication of STOKE, a stochastic superoptimiser▲58

    Haskell re-implementation of STOKE, the stochastic superoptimizer - blaze/notebooks/tutorial.ipynb at master · bollu/blaze

    2019 · github.com · its alternatives →

21. 21
    Cppmatch – Rust-Like Pattern Matching and Error Handling for C++▲42

    I've created cppmatch, a lightweight, header-only C++ library that brings Rust-inspired pattern matching and error handling to C++. It tries to imitate the functionality of the questionmark (?) operator in C++ by using a macro that uses the gcc extension https:&#x2F;&#x2F;gcc.gnu.org&#x2F;onlinedocs&#x2F;gcc&#x2F;Statement-Exprs.html This allows to create exceptionless code with non-intrusive error-as-value that unlike Exceptions, makes it clear which kinds of error a function can generate and forces you to handle (or ignore) them. The ? operator translates to *expect* To handle the errors I…

    2025 · github.com · its alternatives →

22. 22IB
    I built a minimal Forth-like stack interpreter library in C▲47

    This weekend I created stacklib.h - a single-header library that brings Forth-style stack operations to C. It implements a basic interpreter with: - Stack operations (push&#x2F;pop&#x2F;dup&#x2F;swap&#x2F;over&#x2F;drop) - Arithmetic (+, -, *, &#x2F;) - Output (., emit, cr) - Stack inspection (.s, depth) Example usage: Stack s; stack_init(&s); dict_init(); exec(&s, "10 20 + ."); &#x2F;&#x2F; Prints "30" exec(&s, "1 2 3 4 .s"); &#x2F;&#x2F; Shows stack contents The library is self-contained, requires no dependencies, and handles basic error checking. It was inspired by wanting to understand…

    2025 · its alternatives →

23. 23
    Mom, can we have (Haskell flavored) post-modern C++ at home?▲20

    hspp: An experimental library to bring Haskell Style Programming to C++. - BowenFu/hspp

    2022 · github.com · its alternatives →

24. 24
    Curious Namespace Trick – Limited static polymorphism in C++▲41

    Wiki:. Contribute to dchichkov/curious-namespace-trick development by creating an account on GitHub.

    2016 · github.com · its alternatives →

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →