Build a web app in pure Python.
You'll clone a small study-and-budget planner, run it on your own computer, change it, and put it online — all without writing a single line of HTML. Step by step, no experience needed.
A planner tool, in Python only
hibot-streamlit-tool is an interactive web app — sliders, inputs, and results that update live. The surprising part: it's written entirely in Python. Streamlit is a library that turns a plain Python script into a web page, building all the buttons and layout for you. No HTML, no CSS, no JavaScript.
It's the fastest way to put a useful tool in front of people when you only know Python. By the end you'll have it running, changed, and live on the web for free.
Three things to have ready
- Python 3.10 or newerGet it from python.org. To check what you have, open a terminal and type
python --version. - A terminalThe text window where you type commands. It's called Terminal on Mac/Linux and PowerShell on Windows — both work.
- A code editor (recommended: Cursor)Any editor opens the files. We like Cursor because its built-in AI can explain each line and help when you get stuck.
Let an AI editor sit beside you
Cursor is a code editor with an AI built in. Open the project in it and you can highlight any line and ask "what does this do?", or describe a change in plain English and watch it edit the file. New builders get 50% off their first month through our link.
From clone to live, one step at a time
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Get the code onto your computer
In your terminal, "clone" the repo — that just means download a copy you can edit. Then step into the new folder.
# copy the project to your computer git clone https://github.com/Cartooli/hibot-streamlit-tool.git cd hibot-streamlit-toolNo Git installed? On the repo page, click the green Code button → Download ZIP, then unzip it.
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Install what it needs
The app needs Streamlit and a couple of helpers. This one command installs them all.
pip install -r requirements.txtIf
pipisn't found, trypip3orpython -m pipinstead. -
Run it on your own machine
Streamlit has its own run command. It will open the app in your browser automatically.
streamlit run app.pyIf it doesn't open on its own, go to
http://localhost:8501. Move the sliders and inputs — the results update instantly. That's your app. -
Look around the files
Open the folder in your editor. There are only a few pieces:
app.py— the screen: every widget (slider, input, button) and how the page is laid out.
logic.py— the calculations, kept separate so they're easy to read and test.
sanitize.py— cleans up user input so it's safe.
tests/— automatic checks that prove the logic still works. -
Make your first change
Open
app.pyand find the page title. Streamlit widgets are just function calls — change the title text:# before st.title("Study & Budget Planner") # after st.title("Alex's Planner")Save the file. Streamlit notices and shows a Rerun button in the corner — click it (or just reload). Your change is live. Next, try adding a new
st.slider(...)and see it appear. -
Save your work with Git
Lock in your change. Make your own empty repo on GitHub first, then:
git add . git commit -m "Make the planner mine" git remote set-url origin https://github.com/YOUR-USERNAME/YOUR-REPO.git git push -u origin mainNew to this? Our guide to pull requests walks through saving and publishing work on GitHub.
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Put it on the internet
The free and easy path is Streamlit Community Cloud: sign in with GitHub, pick your repo and
app.py, and click deploy. A minute later you'll have a public link anyone can use, and it updates every time you push.
Totally normal — here's the fix
- "command not found: streamlit"The install didn't finish. Re-run
pip install -r requirements.txt, or trypython -m streamlit run app.py. - "command not found: python"Try
python3instead. If neither works, install Python from python.org. - The browser didn't openThat's fine — just go to
http://localhost:8501yourself. - My change didn't showSave the file, then click Rerun in the top-right of the app (or reload the page).
Keep building
Try another starter, or dig into the tools.
You built a Python web app. What's next?
Open the live sample, see how it behaves, then keep going. New builders: let Cursor write the next version with you — 50% off your first month through our link.