Hailstorm : A Statically-Typed, Purely Functional Language for IoT Applications

TL;DR

Hailstorm is a new statically-typed, purely functional programming language designed for IoT devices, offering high-level abstractions, memory safety, and resource-aware type tracking to improve IoT application development.

Contribution

It introduces Hailstorm, a high-level functional language with static typing and resource-aware features tailored for resource-constrained IoT devices, addressing limitations of C.

Findings

Successfully implemented IoT applications like earthquake detection and railway crossing systems.

Demonstrated Hailstorm's capability on embedded hardware like the GRiSP board.

Explored the design of a purely functional language with resource tracking for IoT.

Abstract

With the growing ubiquity of Internet of Things(IoT), more complex logic is being programmed on resource-constrained IoT devices, almost exclusively using the C programming language. While C provides low-level control over memory, it lacks a number of high-level programming abstractions such as higher-order functions, polymorphism, strong static typing, memory safety, and automatic memory management. We present Hailstorm, a statically-typed, purely functional programming language that attempts to address the above problem. It is a high-level programming language with a strict typing discipline. It supports features like higher-order functions, tail-recursion, and automatic memory management, to program IoT devices in a declarative manner. Applications running on these devices tend to be heavily dominated by I/O. Hailstorm tracks side effects likeI/O in its type system using resource types. This choice allowed us to explore the design of a purely functional standalone language, in an area where it is more common to embed a functional core in an imperative shell. The language borrows the combinators of arrowized FRP, but has discrete-time semantics. The design of the full set of combinators is work in progress, driven by examples. So far, we have evaluated Hailstorm by writing standard examples from the literature (earthquake detection, a railway crossing system and various other clocked systems), and also running examples on the GRiSP embedded systems board, through generation of Erlang.