Python (no run) with PairPad
The pad opens with main.py, a small dataclass and two functions with type hints and a TODO, plus review.md for notes. Python is highlighted and editable by everyone in the room, but it does not run in PairPad: this page is for writing, reviewing and talking through Python together.
- Read main.py together. The expected output of each print call is written next to it, so you can reason about the code without running it.
- Press Share and send the link. Your partner opens it without an account; you see each other's cursors and selections and can both type in main.py at the same time.
- Select a line to point at it while you talk, and write decisions in review.md, for example what most_frequent_customer should return on a tie.
- When you want real output, copy main.py into your own environment and run python3 main.py; with Pro you can download the room as a .zip.
- If you need code that runs for everyone in the room, rename the file to .js or .sql: JavaScript, TypeScript and SQL run in PairPad with shared output.
What to know
To be clear about what this is: PairPad highlights Python and lets several people edit it live, but it has no Python interpreter. Pressing Run on a .py file shows a message instead of output. If running the code in the browser is what you need, a notebook or an online Python interpreter is the right tool; if what you need is two people looking at and changing the same Python file right now, this is that, with nothing to install and no account for either of you.
That covers more sessions than it sounds. Code review of a function before it is committed, walking a junior developer through a script, whiteboard-style interviews where the candidate is expected to reason about the code rather than execute it, and drafting a script together that you will run on a machine with the right data and packages anyway. Writing the expected result next to each call, as main.py does, turns "does it work?" into a conversation you can have without running it.
The example uses Python features people often get asked about: @dataclass for a typed record without boilerplate, built-in generics in hints (list[Order], dict[str, float], Python 3.9+), dict.get with a default to accumulate totals, and collections.Counter.most_common. The tie question in the TODO has a precise answer: most_common orders elements with equal counts in the order they were first encountered, so the first customer seen wins a tie.
Edits from everyone merge through a CRDT, so two people changing the same function at once both keep their changes. A free room keeps 2 files and is deleted 24 hours after the last activity. Pro ($29 once) adds unlimited files (utils.py, test_main.py, requirements.txt), a .zip download, keystroke replay, private interviewer notes and a scorecard, and rooms that never expire.
Updated · Cosmovex
Questions
Can I run Python code in PairPad?
No. Python files are highlighted and editable, but there is no Python interpreter, and Run shows a message instead of output. JavaScript, TypeScript and SQL do run, with output shared in the room.
Then what is the Python pad for?
Editing and discussing Python with someone live: code review, mentoring, whiteboard-style interviews and drafting a script you will run locally. Both of you type in the same file with live cursors, with no account and nothing to install.
Does the editor indent Python correctly?
Yes. The Python mode highlights syntax and continues indentation after a colon, and Tab indents. Indentation is shared character for character, so what your partner sees is exactly what will run locally.
How do I get the code out to run it?
Copy the file into your editor and run it with python3 main.py on your machine. With Pro you can download the whole room as a .zip.
Can I use it for a Python interview?
Yes, for interviews that do not need execution. Paste the question at the top of main.py, press Share before the call and send the link. If the candidate needs to run code, choose a language that runs here or use a tool with a Python interpreter.
The free plan covers everything on this page. PairPad Pro ($29, paid once) is described on the PairPad page.
