Electronic – arduino – Which programming languages are supported to program Arduino

ARMPIT SCHEME is an interpreter for the Scheme language (lexically-scoped dialect of Lisp) that runs on RISC microcontrollers with ARM core. It is based on the description in the Revised Report on the Algorithmic Language Scheme (r5rs), with some extensions (for I/O) and some omissions (to fit within MCU memory). It is further designed to support multitasking and multiprocessing. Armpit Scheme is expected to be well suited to educational settings, including student projects in courses on control and instrumentation, or capstone design courses where microcontrollers are needed. It is meant to enrich the spectrum of interpreted languages available for MCUs (eg. BASIC and FORTH) and can be an alternative to MCU-based bytecode interpreters (eg. for Scheme or Java) and to compiled languages (eg. C).

http://armpit.sourceforge.net/

You say:

Using C, C++, assembly, etc. is quite inefficient compared to languages like Haskell, LISP, or Scheme

Using high level languages is a more efficient use of programmer time, but can often be a less efficient use of computing resources. For embedded systems manufactured in volume, cost and performance are often higher priority than development effort.

You could use an AVR micro-controller in your product to run the code you develop on an Arduino development board.

The Arduino is a good development and prototyping platform because it comes with a lot of hardware facilities ready to use, but that's what makes it too expensive for a product. You can use the same, or a similar, kind of micro-controller chip in your product without the whole Arduino board around it.

This page from the Arduino website describes how to bread-board a bare AVR controller chip and crystal, and load your Arduino program into it.