Using python to find the first frost: cassidoo's interview question of the week (2026-09-28).

Using rust to find all the Sundays in a given month; cassidoo's interview question of the week (2026-09-21)

Using ruby to find the longest word whose letters appear in alphabetical order; cassidoo's interview question of the week (2026-09-14).

Lessons from aviation and nuclear power show how to preserve human skills

Using python to unlock a backpack: cassidoo's interview question of the week (2026-09-06).

Using Copilot CLI to build a simple app to find gift suggestions based on my 5-star reviews and their Goodreads wishlist.

Using pascal to climb stairs; cassidoo's interview question of the week (2026-08-31).

Using rust to pack boxes; cassidoo's interview question of the week (2026-08-16).

Using ruby to reorder string arrays and compare algorithms: cassidoo's interview question of the week (2026-08-03).

Using python to run an ice cream stand: cassidoo's interview question of the week (2026-07-27).

Testing some push-button switches with built-in LEDs. I've used a CD4069 inverter-based latching circuit to demonstrate toggling the LED on and off.

Using ruby to calculate the blast radius of some fireworks; cassidoo's interview question of the week (2026-07-06).

Introducing the CD4024 7-stage binary counter with a basic demonstration circuit.

Using Perl to calculate mean bits; cassidoo's interview question of the week (2026-06-29)

Michel Kuka Mboladinga is iconic for his motionless tribute at DRC games, but a US World Cup repeat has been denied.

Investigate acoustic levitation by building a cheap ultrasonic levitator kit that uses common 40kHz ultrasonic transmitters driven by STC15F101W microcontroller and a TC4427 power MOSFET.

Simplest LED blinky program in C for the AT89C2051(8051/MCS51) microprocessor, built with the SDCC open-source toolchain on macOS. Originally tested with Intel-based macOS, but now updated for Apple S...

Using Perl to play solitaire; cassidoo's interview question of the week (2026-06-08).

A simple 2d6 dice roller using Arduino and ATtinyA little 1d6 or 2d6 dice roller using the TM1638 and ATtiny85.

Test a total power shutdown with an ATtiny85 processor on a breadboard: power-on with push-button PFET; power-off by the microprocessor itself.

Using Perl to pack suitcases; cassidoo's interview question of the week (2026-06-01).

Using Perl to move every nth customer to the end of the queue; cassidoo's interview question of the week (2026-05-25).