Launch HN: Artemis (YC S22) – Use comments to give code an interactive interface
Hello Hacker News, we’re Austin, Manvir, and Kyle, the cofounders of Artemis Labs
(https://artemisdevtool.com). We turn your in-line comments into a UI that can be used to
visualize, test, document and share your code. This helps engineers and scientists quickly
create quality scripts.

Artemis was born in a Caltech robotics lab where I saw firsthand how much time and effort it
took to create a quality script. Engineers were spending hundreds of hours making
slide decks, hybrid Markdown / LaTeX documents, and demo GUIs just to make their tools
accessible and usable by others. As someone who has been on the learning end of things, it
can be nearly impossible to decipher or use even the smallest scripts if they lack quality
documentation and interactive interfaces. Although these methods worked they were an
incredible time sink and documentation became stale quickly.

Artemis was devised as a solution to this problem. We wanted a tool that allows developers to
create high-quality interfaces and documentation without forcing them to invest substantial time,
alter their codebases or make significant changes to their workflows.

The way it works is simple: First add special comments to your codebase; Artemis uses these
comments (called “anchors”) to automatically generate a GUI for your code. Then run your
program using our command-line utility. Artemis launches in an offline browser window that
displays your code on one side and your new interface on the other. To see how this looks, you
can watch our demo video here: https://www.youtube.com/watch?v=IDL12DkS2Hc.

This interface scrolls vertically, so as your code runs new GUI elements appear one below
another at the relevant time organized into “cards.” For example, if a program takes two
numbers and adds them, your interface will first show input fields for the variables in one card.
When you enter numbers and press “continue,” a new card showing the result will appear.

There are three types of anchors: inputs, outputs and documentation. Inputs let you change
variables in your program via the interface, outputs represent the products of your program as
graphs, text, etc. and documentation lets you create interface elements that explain what is
happening as your program runs. Documentation can take the form of text, Markdown, LaTeX,
syntax-highlighted code snippets, multimedia, and links, and more.

These anchors all follow the same format: you put them in a comment, beginning with “@,”
followed by its type— “input,” “output” or “doc.” For “doc” anchors you just proceed to add
whatever you would like to appear in the document card. For inputs and outputs, you need to
specify which variable they act upon by typing “data=x,” with x being your variable.

We provide a suite of default anchors, such as text inputs, and outputs in the form of text,
tables, and graphs—but we also let you create your own, using regular Python. Do you need to
create a custom anchor to quickly display your statistical data using Seaborn? Do you want to
automatically render advanced 3D plots in Matplotlib? Artemis makes this, and more, easy.

The reason we opted to have anchors work from comments is to avoid requiring you to alter
your code or the way you work. You don’t have to toggle between different environments—you
stay in your preferred IDE, bringing more functionality to it rather than requiring you to go
somewhere else.

For example, we subsume the functionality of Jupyter as a visualization tool without requiring
you to use a notebook. In our experience, notebooks are rather constraining relative to a full
Python environment— they require you to restructure your code for the notebook, run your
programs on an IPython kernel, and often import new third-party libraries or widgets. With
Artemis you get the interactivity of a notebook, as well as the display of UI elements and
documentation alongside code, but it also works with professional-grade codebases and tooling.

Artemis interfaces can be exported as an HTML file that runs offline. This is a key feature that
makes us a portable, effective documentation/walkthrough tool. These interfaces are small
enough to send via email and can even be embedded in web pages. When a third party opens
your HTML file, they’ll see exactly what you see when you run your program with Artemis: an
interface on the left and your code on the right.

We thought the most obvious applications of this approach would be for quickly building
interactive computational tools and making test scaffolding for complex programs. But it turned
out to also be really good for making code walkthroughs that can explain your program to
coworkers or managers, or teach people how to use your program. You can see this in action here: https://www.youtube.com/watch?v=V4c3Q6lHFPo.

Engineers at Mayo Clinic use Artemis in this way, using our Markdown, LaTeX, and multi-media
documentation capabilities coupled with custom anchor outputs to produce step-by-step
walkthroughs for their internal tools.

Artemis is ready to go, and we offer a free trial on our website. Setup and installation only take a
minute, but we’d also be delighted to answer your questions personally and/or give you a
walkthrough—we like to meet our users!

Our current pricing model is $15/month for basic Artemis. There’s a pro version that allows you
to create custom anchors (beyond inputs, outputs and doc), and export your interfaces as HTML
files. We also do the “contact us” enterprise thing for larger teams.

We’ll be around in the comments below and are super interested in whatever you have to say!