Pe

Pe is a libadwaita and ModemManager based UPI client for Linux Desktops and Linux Mobile phones, written in Python.

Backend

This client utilises *99# service publically available on Airtel, Vi, BSNL (not Jio), provided by NCPI.

It is prone to failing, because of the nature of USSD service, and network strengths.

Disclaimer

The developer is not reponsible for any loss of money or any complications. So, try on your own risk.

How to use

Pe provides two binaries pe and pe-cli. By default, launnching the app through flatpak would launch ‘pe’ which is the graphical app. But you can optionally run the pe-cli binary, which provides a command line interface..

Additional system requirements

As it uses the *99# USSD service, it requires a modem connected. While linux phones already have built-in modem, some laptops also have inbuilt WAN or SIM ports. You may also connect Linux-compatible modems to your computer.

ModemManager service is already installed and enabled by default in distros like Ubuntu, Fedora. But, it may not be installed in other distros. You need to install ModemManager and enable it in your distro (that doesn't always require systemd, if you are using an init system other than systemd, you can still launch the service through your respective init system).

Development notes

It was GTK4/Libadwaita learning project for me, so I have fairly documented the GUI code.

As the app is currently in development, I have not implemented a lot of error handling. The app would not even start in absence of modem, if built with normal profile. There exists a testing profile, which does a dry run, and does not utilise any modem, and is there only for testing the GUI

The GUI code is separated from backend code. So, in case in future, we come forward to use some backend other than USSD, just utils.py can be replaced to provide the same functions.

How to run

The most easy way to run this app, is using GNOME Builder, or using Flatpak extension for VS Code or VSCodium. I have provided two flatpak manifests, one for normal profile and one for testing profile.

Though you can also build the project locally, without Flatpak by:

meson build -Dprofile=testing
cd build
sudo meson install

(testing mode)

meson build 
cd build
sudo meson install

(normal mode)

What works currently in GUI

• Fetching balance

What works currently in CLI

• Completing a requested payments
• Fetching a payment request
• Creating a payment request to UPI ID, phone number, saved beneficiary
• Sending payment to UPI ID, phone number, saved beneficiary, bank account (IFSC code and account number)
• Fetching balance
• Determining number of ditgits in PIN

More plans

• Processing upi:// links and automating handling them, which are contained in a QR code
• Directly processing a QR code image (integrating camera to directly scan is not planned, users would be required to use any QR app like 'Decoder' to scan code, and open the link via this app, which would then be handled)