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Comment by MomsAVoxell | Hacker News Reader

I think its really cute that SQlite is used as the container format - but my mind wanders to other things used in the same way.

One of my favourite ways to develop apps is to use Lua - for everything. Construct an efficient core application framework, then embed the Lua VM in it, and then do all program logic and control flow in Lua, then put the Lua bytecode in the binary with luastatic, and off we go.

So this technique could be used to tack on state as Lua bytecode, meaning I could then accomplish something I’ve wanted for my Lua apps for decades - migration. I could have the app save its state safely, then simply transfer the binary itself to another machine, and recover gracefully.

Of course this could be used with any tools - not just Lua - but the idea of having the entire runtime binary included in the Lua state table is just so delicious I wanna try it ..

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> One of my favourite ways to develop apps is to use Lua - for everything. Construct an efficient core application framework, then embed the Lua VM in it, and then do all program logic and control flow in Lua, then put the Lua bytecode in the binary with luastatic, and off we go.

Okay, you have to expand on this. Do you have a blog post or anything that goes into more detail?

I don't have an article or blog post, alas.

Basically, take your application framework of choice - in my case its JUCE (C/C++) - and embed a Lua VM in it. Put the UI in the framework, and then encode all of the program logic and application control flow in Lua, which marshals the UI and the rest of the system through the VM interface.

Sure, you can just 'do everything in C/C++', but I've found that for long-term projects, doing app logic in Lua, a simpler language to wrangle, has been very fruitful. And, it puts the framework in an interesting context - serving the VM - which reduces bugs and keeps things pretty tidy. Most of the C/C++ code is just UI and system-level scaffolding - which I then write Lua tests for - and then once this is in place, the app logic is very productively developed and shipped as byte code. The App becomes a host for the logic.

Do you have any problems with antivirus or Defender complaining about the embedded VM?

Never. But I deploy in controlled environments where my .exe is well known before install.

I think there are false negatives in some of the lesser-maintained antivirus tools - but I have never had issues with it.

Isn’t this similar to what Redbean does (which inspired this queriable executable idea), except that in Redbean the application is web server based?

Actually its a core feature of the Lua VM as an applicable technology - Lua is literally embedded all over the place.

My favourite other example is turboLua:

https://turbo.readthedocs.io/

I am not sure this is the same kind of thing. In Redbean, you have a single executable that runs on any Operating System (that's right, the same executable file, this is enabled by CosmopolitanC) and that executable has a SQLite DB inside that can be used by the Lua code, which is also itself inside the executable file, and it can be modified at will and still run. I think most people don't realize just how crazy this is. It's a lot more than LuaVM embedded in a "normal" C executable.

    $ luastatic —help

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