Rust Glancer: A Rust LSP that runs on under 100MB of RAM

Rust language servers are notorious memory hogs, but a new tool keeps editor analysis under 100MB of RAM.

A developer released Rust Glancer, an alternative Rust LSP focused on low memory usage. Standard tools like rust-analyzer keep query databases in memory, which leads to high RAM usage and memory fragmentation. Rust Glancer takes a different route: it offloads analysis results to the filesystem and loads them only when needed. In tests on an 8GB M1 MacBook Pro, base indexing took six seconds while keeping RAM usage under 100MB.

Why it matters: Rust developers on older machines or laptops with limited RAM often watch their editor consume gigabytes of memory. Rust Glancer trades microsecond keystroke analysis for lower memory usage, holding off on full re-indexing until you save the file.

Know this: The project is four months old and incomplete compared to rust-analyzer. However, it already supports basic LSP actions like hover, goto definition, completions, and inlay hints. You can install the VS Code extension directly or build it from the repository.

Your laptop fans might finally get a break.