A new technique leverages a modified LLVM fork to retrofit JIT compilation directly into C-based interpreters by optimizing the interpreter's underlying execution loop. By manually annotating the interpreter's C code, developers can significantly boost performance, such as doubling execution speed for Lua, without altering the actual programs being interpreted. While the approach currently requires specialized knowledge and manual modifications, it offers a promising method for accelerating language interpreters that could potentially be automated in the future.