Arduino have just released two new boards based on the Renesas RA4M1 ARM Cortex M4 CPU running at 48 MHz.
The boards maintain the same form factor, shield compatibility, and 5V operating voltage as the original ATmega328P-based Arduino Uno, and all the I/O pins on the Arduino Uno R4 boards operate with 5 V logic, making them compatible with 5 V peripherals.
Arduino Uno R4 Minima
The Arduino Uno R4 Minima has 256 KB flash memory and 32 KB RAM.
Arduino Uno R4 WiFi
In addition, the Arduino Uno R4 WiFi includes an ESP32-S3 module to provide WiFi and Bluetooth, an on-board 12x8 LED matrix, I2C on a Qwiic/STEMMA QT connector, and a real-time clock.
I hope to have a version of uLisp that supports both boards soon.
For more details see the Arduino website: Arduino UNO R4