STM32G031J6

In December, 2018, STMicro announced their STM32G0 line of microcontrollers. https://blog.st.com/stm32g0-mainstream-90-nm-mcu/
The STM32G031J6 is the first STM32 powered, 8pin micro, in their value line to compete with traditional 8-bit and 16-bit micros in the economy space.

Their value line:
https://www.st.com/en/microcontrollers-microprocessors/stm32g0x0-value-line.html

STM32G0 Discovery Kit STM32G0316-DISCO: ($10.53 from Digikey)
https://www.digikey.com/product-detail/en/stmicroelectronics/STM32G0316-DISCO/497-19570-ND/10321672
Data Brief: https://www.st.com/resource/en/data_brief/stm32g0316-disco.pdf

Digikey offers the STM32G031J6M6 for $1.43 (single quantity)
https://www.digikey.com/products/en/integrated-circuits-ics/embedded-microcontrollers/685?k=STM32G031J6

Digikey offers the STM32G030J6 for $0.40 when purchasing 2000 pcs.
https://www.digikey.com/products/en?keywords=STM32G030J6

STM32G0 Getting started - hardware development document: https://www.st.com/resource/en/application_note/dm00443870-getting-started-with-stm32g0-series-hardware-development-stmicroelectronics.pdf

ST Website for the STM32G0 family: http://www.st.com/stm32g0 Product overview document, 117 pages: https://www.st.com/resource/en/datasheet/stm32g031j6.pdf