https://prescheme.org/

Pre-Scheme is a statically typed dialect of the Scheme programming language, combining the flexibility of Scheme with the efficiency and low-level machine access of C. The compiler uses type inference, partial evaluation, and other correctness-preserving transformations to compile a subset of Scheme into C with no additional runtime overhead. This makes Pre-Scheme a viable alternative to C for programming virtual machines, operating systems, and embedded systems where the runtime overhead of a complete Scheme implementation is not desirable.

https://ryansuchocki.github.io/microscheme/

Microscheme, or (ms) for short, is a functional programming language for the Arduino, and for Atmel 8-bit AVR microcontrollers in general. Microscheme is a subset of Scheme, in the sense that every valid (ms) program is also a valid Scheme program (with the exception of Arduino hardware-specific primitives). The (ms) compiler performs function inlining, and features an aggressive tree-shaker, eliminating unused top-level definitions. Microscheme has a robust FFI (Foreign Function Interface) meaning that C code may be invoked directly from (ms) programs. Therefore, the power of the existing wealth of Arduino libraries is available within Microscheme.