Agents can now port code bases much better than before.

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Armin Ronacher

An experienced developer successfully ported MiniJinja, a Rust-based Jinja2 template engine, to native Go using AI agents with minimal manual intervention. The process took about 45 minutes of active guidance and 10 hours of autonomous agent work, leveraging snapshot tests for validation and incremental porting (lexer → parser → runtime). The agent evolved from literal code translation to behavioral porting, making idiomatic Go decisions like using reflection and tree-walking interpretation. The experience highlights how AI agents are making cross-language ports feasible with less effort, shifting value from code to tests and documentation, while changing the social dynamics of open source porting.

Porting MiniJinja to Go With an Agent

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A good test suite might actually be worth more than the code.
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Agreed, I also got that feeling for a while now. In my opinion the port is a nice demonstration but hopefully will ultimately become unnecessary. In my mind a port is a symptom of lock-in. A Python library becomes successful, gets ported to Ruby, Java, JavaScript because you cannot reasonably call one from the other. If you lower the level enough, this changes. A library written in C can be called from anywhere, it’s mostly a matter of adding glue code. If you carefully design interfaces, this should be much less effort compared to maintaining n ports. But writing C (or even Go, Rust) is for many people much more effort than doing Python or JavaScript which they love and are much easier for prototyping something.
Well, this changes. I guess I could still start something in Python to get instant gratification and port it later but why not leave out the port, define the interface, create something native with vastly better performance and generate glue code for every language ecosystem I care about?
This is a bit of an oversimplification but honestly, I get this thought a lot these days and “LLM x generated this production grade app in 1h” is as much an exaggeration.