skim-rs/skim v4.0.0

4.0.0 - 2026-03-10

on GitHub

Release Notes

Changes

sk is now beating fzf in interactive matching for time, peak memory usage and CPU usage ! See the benchmarks below for details, including a brief explanation of the benchmark itself.

This release brings multiple breaking changes, please read the following if you have doubts about the update.

Default to the Arinae matcher

The biggest change of them all is that the default algorithm is now Arinae, skim's latest and most performant algorithm, featuring typo-resistance. If you want to keep using SkimV2, pass --algo skim_v2 and please take the time to open an issue explaining why if possible.
This also makes the --scheme option available to the default matcher, allowing for more refined matching scenarii.

Default to non-typo resistant

Typo-resistant behavior is now disable by default, add --typos to your skim invocation or SKIM_DEFAULT_OPTIONS to get it back. Unless you were using the frizbee, fzy or arinae matcher, this should not impact you.

Removal of the skim_v1 algorithm

The SkimV1 algorithm, skim's initial algorithm, has been deprecated for years now, and it has now been removed.

SkimItem index (library only)

SkimItem::get_index and SkimItem::set_index are gone, and all index handling is now done internally.

Benchmarks

This benchmarks runs the interactive interface in a tmux session, and waits for the UI to stabilize.
It uses a 10 million path-like ASCII items input file, and the query test.

=== Results: sk v4.0.0 [baseline] ===
Completed runs: 50 / 50
Average items matched: 2895782 / 10000000  (min: 2895782, max: 2895782)
Average time: 3.827s  (min: 3.576s, max: 4.090s)
Average items/second: 2615767  (min: 2445033, max: 2796365)
Average peak memory usage: 1589.2 MB  (min: 1518.6 MB, max: 1661.2 MB)
Average peak CPU usage: 528.9%  (min: 457.0%, max: 740.0%)

=== Results: sk v3.7.0 ===
Completed runs: 50 / 50
Average items matched: 2895782 / 10000000  (min: 2895782, max: 2895782) +0.0%
Average time: 3.930s  (min: 3.565s, max: 4.226s)  +2.7%
Average items/second: 2548674  (min: 2366263, max: 2804816)  -2.6%
Average peak memory usage: 1618.8 MB  (min: 1539.1 MB, max: 1680.6 MB) +1.9%
Average peak CPU usage: 696.8%  (min: 608.0%, max: 875.0%)  +31.7%

=== Results: fzf 0.70.0 ===
Completed runs: 50 / 50
Average items matched: 2895782 / 10000000  (min: 2895782, max: 2895782) +0.0%
Average time: 5.421s  (min: 4.814s, max: 6.111s)  +41.7%
Average items/second: 1848269  (min: 1636444, max: 2077385)  -29.3%
Average peak memory usage: 2015.3 MB  (min: 1860.7 MB, max: 2173.9 MB) +26.8%
Average peak CPU usage: 1301.1%  (min: 1229.0%, max: 1431.0%)  +146.0%

=== Comparison Summary (vs baseline: sk v4.0.0) ===
Binary      Avg time     Δ time  Avg rate     Δ rate
------------------------------------------------------------------------------
sk v4.0.0   3.827s    baseline   2615767     baseline
sk v3.7.0   3.930s      +2.7%    2548674      -2.6%
fzf 0.70.0  5.421s     +41.7%    1848269     -29.3%

🚀 Features

• [breaking] Internally compute indexes at match time (removes get/set_index) (#1001)
• [breaking] Use Arinae as default algorithm

⚙️ Miscellaneous Tasks

• [breaking] Default to disabled typos
• Use python for bench script for comparison

Install skim 4.0.0

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/skim-rs/skim/releases/download/v4.0.0/skim-installer.sh | sh

Download skim 4.0.0