- `nintendoswitch`: support outputting .nro files directly
* **boards**
- `arduino-zero`: Adding support for the Arduino Zero (#1365)
- `atsamd2x`: fix BAUD value
- `atsamd5x`: fix BAUD value
- `bluepill`: Enable stm32's USART2 for the board and map it to UART1 tinygo's device
- `device/atsamd51x`: add all remaining bitfield values for PCHCTRLm Mapping
- `esp32`: add libgcc ROM functions to linker script
- `esp32`: add SPI support
- `esp32`: add support for basic GPIO
- `esp32`: add support for the Espressif ESP32 chip
- `esp32`: configure the I/O matrix for GPIO pins
- `esp32`: export machine.PortMask* for bitbanging implementations
- `esp8266`: add support for this chip
- `machine/atsamd51x,runtime/atsamd51x`: fixes needed for full support for all PWM pins. Also adds some useful constants to clarify peripheral clock usage
- `machine/itsybitsy-nrf52840`: add support for Adafruit Itsybitsy nrf52840 (#1243)
- `machine/stm32f4`: refactor common code and add new build tag stm32f4 (#1332)
- `nrf`: add SoftDevice support for the Circuit Playground Bluefruit
- `nrf`: call sd_app_evt_wait when the SoftDevice is enabled
- `nrf52840`: add build tags for SoftDevice support
- `nrf52840`: use higher priority for USB-CDC code
- `runtime/atsamd51x`: use PCHCTRL_GCLK_SERCOMX_SLOW for setting clocks on all SERCOM ports
- `stm32f405`: add basic UART handler
- `stm32f405`: add STM32F405 machine/runtime, and new board/target feather-stm32f405
* **build**
- `all`: run test binaries in the correct directory
- `build`: Fix arch release job
- `ci`: run `tinygo test` for known-working packages
- `ci`: set git-fetch-depth to 1
- `docker`: fix the problem with the wasm build (#1357)
- `Makefile`: check whether submodules have been downloaded in some common cases
* **docs**
- add ESP32, ESP8266, and Adafruit Feather STM32F405 to list of supported boards