original: {key:64};
Let's say, std::uint64_t x = dom["key"].getuint64();
x = 64;
If I modify the dom pointer value to 70;
the simdjson's minify() and similar methods that prints the JSON in string should output:
new: {key:70};

I got your point.
But the issue that I'm currently facing is,
I need to figure out a way to make changes to certain fields and write it back to file or string.
While maintaining the field and properties order.
I'm okay with migrating to C++26 or beyond.

See #2282

See #2282

I'm not quite sure If reflection would work for me since it expects a struct which is pre-defined.
(Meaning, the JSON structure should be known at compile time)
But for me, I know that the JSON would contain certain fields, but not their order or all fields in compile time.
For instance, Rapidjson allows me to do exactly that.
Gist: https://gist.github.com/iamAzeem/0a1feb4e8104b8970b26767ef344d23e#file-rapidjson_file_read_write_test-cpp

doc[ "ip" ] = "127.0.0.1";

#include <iostream>
#include <fstream>
#include <cstdlib>
#include <rapidjson/document.h>
#include <rapidjson/istreamwrapper.h>
#include <rapidjson/writer.h>
#include <rapidjson/stringbuffer.h>
#include <rapidjson/ostreamwrapper.h>

int main()
{
    using namespace rapidjson;

    std::ifstream ifs { R"(C:\Test\Test.json)" };
    if ( !ifs.is_open() )
    {
        std::cerr << "Could not open file for reading!\n";
        return EXIT_FAILURE;
    }

    IStreamWrapper isw { ifs };

    Document doc {};
    doc.ParseStream( isw );

    StringBuffer buffer {};
    Writer<StringBuffer> writer { buffer };
    doc.Accept( writer );

    if ( doc.HasParseError() )
    {
        std::cout << "Error  : " << doc.GetParseError()  << '\n'
                  << "Offset : " << doc.GetErrorOffset() << '\n';
        return EXIT_FAILURE;
    }

    const std::string jsonStr { buffer.GetString() };

    std::cout << jsonStr << '\n';

    doc[ "ip" ] = "127.0.0.1";

    std::ofstream ofs { R"(C:\Test\NewTest.json)" };
    if ( !ofs.is_open() )
    {
        std::cerr << "Could not open file for writing!\n";
        return EXIT_FAILURE;
    }

    OStreamWrapper osw { ofs };
    Writer<OStreamWrapper> writer2 { osw };
    doc.Accept( writer2 );

    return EXIT_SUCCESS;
}

Please read our documentation:

• On-Demand JSON: A Better Way to Parse Documents?
• The Basics

In simdjson, if you need to parse the content, you are expected to provide your own data structures.

It looks like you want an old school mutable DOM tree. There are indeed many good options (such as RapidJSON) for this purpose. But not simdjson.

I figured out, A mutable DOM tree is what I'm looking for.
I understand that a mutable DOM might be unsafe but there are also valid use cases for that.
If the program takes the responsibility and necessary precautions, it should be fine.
Is there any Issue/PR that's working on it?

@Lucienest We moved away from a DOM approach. We explain in details why in this article: On-Demand JSON: A Better Way to Parse Documents?.