Speedup gem loading

[byroot]

github-linguist is pretty slow to load, in large part because it has to parse a pretty large json blob (~35ms on my machine).

Instead of shipping this data as JSON, we could ship it directly as Ruby code. By default, the Ruby parser perform about as well as JSON & Yajl:

ruby 4.0.5 (2026-05-20 revision 64336ffd0e) +YJIT +PRISM [arm64-darwin25]
Calculating -------------------------------------
                json     27.363 (± 3.7%) i/s   (36.55 ms/i) -    138.000 in   5.043304s
                yajl     28.111 (± 3.6%) i/s   (35.57 ms/i) -    142.000 in   5.051466s
                load     27.719 (± 3.6%) i/s   (36.08 ms/i) -    140.000 in   5.050659s

Comparison:
json:       27.4 i/s
yajl:       28.1 i/s - same-ish: difference falls within error
load:       27.7 i/s - same-ish: difference falls within error

But with Bootsnap, which can probably be assumed of many users, it's over 4 times faster to load the data:

ruby 4.0.5 (2026-05-20 revision 64336ffd0e) +YJIT +PRISM [arm64-darwin25]
Calculating -------------------------------------
                json     28.350 (± 3.5%) i/s   (35.27 ms/i) -    142.000 in   5.008777s
                yajl     30.316 (± 3.3%) i/s   (32.99 ms/i) -    152.000 in   5.013793s
       load+bootsnap    128.326 (± 4.7%) i/s    (7.79 ms/i) -    650.000 in   5.065217s

Comparison:
         json:       28.4 i/s
load+bootsnap:      128.3 i/s - 4.53x  faster
         yajl:       30.3 i/s - same-ish: difference falls within error

This approach could even be taken faster by directly generating Ruby code that calls Language.create witht he relevant arguments, but I decided to scope this change to the smallest possible one as to test the waters.

Benchmark

# frozen_string_literal: true

require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'
  gem 'yajl-ruby'
  gem 'json'
  gem 'benchmark-ips'
  gem 'bootsnap'
end

require 'json'
require 'yajl'
require 'benchmark/ips'
if ENV["BOOTSNAP_CACHE_DIR"]
  require 'bootsnap/setup'
end

Benchmark.ips do |x|
  x.report('json') { JSON.parse(File.read("lib/linguist/samples.json"))}
  x.report('yajl') { Yajl.load(File.read("lib/linguist/samples.json"))}
  x.report(ENV["BOOTSNAP_CACHE_DIR"] ? 'load+bootsnap' : 'load') { mod = Module.new; load("lib/linguist/samples_data.rb", mod); mod::DATA }
  x.compare!(order: :baseline)
end

[byroot]

NB: since the code is pretty printed, it could make sense to commit it, with some tests to ensure it's upda to date.

[byroot]

This is no longer needed, and was about 5% of load time.