ESP32-C3 is a single-core, 32-bit, RISC-V-based MCU with 400KB of SRAM, which is capable of running at 160MHz. It has integrated 2.4 GHz Wi-Fi and Bluetooth 5 (LE) with a long-range support. It has 22 programmable GPIOs with support for ADC, SPI, UART, I2C, I2S, RMT, TWAI, and PWM.

The greatest thing about this microcontroller is how cheap it is. On AliExpress it costs a mere 2.65 USD each. I bought two of these which in total cost 8.07 USD with shipping included, which is 4.035 USD each. It's also quite nice that the ESP32-C3 uses a RISC-V architecture. LLVM currently doesn't support Xtensa by default (which the ESP32 uses), and Rust depends on LLVM. I'd much rather use Rust than C for programming microcontrollers.