Why Rust Analyzer Is Replacing RLS: Faster IDE Support in Rust 1.64

Rust language server (RLS) final version will be released together with Rust 1.64 in September 2022, after which RLS will be deprecated and replaced by Rust Analyzer.

Both RLS and Rust Analyzer implement the Language Server Protocol (LSP), enabling IDEs to provide static analysis features such as error detection, code completion, and custom navigation, thereby boosting developer productivity.

Supported editors include VS Code, Visual Studio, Vim/Neovim, Sublime, Eclipse, and Emacs.

RLS relies on rustc’s “save analysis” mode, which compiles code in the background and parses the output, a process that is relatively slow.

Rust Analyzer uses a faster incremental compilation mechanism and became an official part of the Rust project in February, quickly proving itself as the most promising IDE integration.

Over 1,000 unresolved issues remain, reflecting community interest and the complexity of Rust Analyzer; the RFC that made it the official Rust LSP was described as the most positively received Rust RFC ever.

According to the 2021 Rust developer survey, the most popular Rust IDEs are VS Code (53.69%) and Vi/Vim/Neovim (28.15%), with JetBrains IDEs at 21.24% offering their own Rust plugin that does not require Rust Analyzer.

Rust 1.62 introduced features such as cargo add for adding dependencies from the command line, default values for enum variants, lightweight mutexes on Linux, and easier building of no‑std binaries for kernel development.

Rust follows a six‑week release cycle, creating a new beta branch each cycle and promoting the previous beta to stable, which reduces pressure on volunteers by allowing unfinished features to be delayed without immediate release concerns.