diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9f9a27b..f4a6f2c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,7 +20,6 @@ jobs:
       fail-fast: false
       matrix:
         ruby:
-          - "3.0"
           - "3.1"
           - "3.2"
           - "ruby-head"
diff --git a/Gemfile.lock b/Gemfile.lock
deleted file mode 100644
index 6f92d75..0000000
--- a/Gemfile.lock
+++ /dev/null
@@ -1,84 +0,0 @@
-PATH
-  remote: .
-  specs:
-    invoice_printer (2.3.0)
-      e2mmap
-      json (~> 2.1)
-      matrix
-      prawn (~> 2.4)
-      prawn-table (~> 0.2.2)
-    invoice_printer_server (2.3.0)
-      invoice_printer (= 2.3.0)
-      json (~> 2.1)
-      puma (>= 3.9.0)
-      roda (~> 3.5)
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    Ascii85 (1.1.1)
-    afm (0.2.2)
-    benchmark_driver (0.15.17)
-    benchmark_driver-output-gruff (0.3.1)
-      benchmark_driver (>= 0.12.0)
-      gruff
-    bigdecimal (3.1.8)
-    e2mmap (0.1.0)
-    gruff (0.25.0)
-      bigdecimal (>= 3.0)
-      histogram
-      rmagick (>= 5.5)
-    hashery (2.1.2)
-    histogram (0.2.4.1)
-    json (2.7.2)
-    matrix (0.4.2)
-    minitest (5.25.1)
-    nio4r (2.7.3)
-    observer (0.1.2)
-    pdf-core (0.10.0)
-    pdf-inspector (1.3.0)
-      pdf-reader (>= 1.0, < 3.0.a)
-    pdf-reader (2.12.0)
-      Ascii85 (~> 1.0)
-      afm (~> 0.2.1)
-      hashery (~> 2.0)
-      ruby-rc4
-      ttfunk
-    pkg-config (1.5.6)
-    prawn (2.5.0)
-      matrix (~> 0.4)
-      pdf-core (~> 0.10.0)
-      ttfunk (~> 1.8)
-    prawn-table (0.2.2)
-      prawn (>= 1.3.0, < 3.0.0)
-    puma (6.4.3)
-      nio4r (~> 2.0)
-    rack (3.1.7)
-    rack-test (2.1.0)
-      rack (>= 1.3)
-    rake (13.2.1)
-    rmagick (6.0.1)
-      observer (~> 0.1)
-      pkg-config (~> 1.4)
-    roda (3.85.0)
-      rack
-    ruby-rc4 (0.1.5)
-    ttfunk (1.8.0)
-      bigdecimal (~> 3.1)
-
-PLATFORMS
-  arm64-darwin-22
-  ruby
-
-DEPENDENCIES
-  benchmark_driver (= 0.15.17)
-  benchmark_driver-output-gruff
-  bundler (>= 1.7)
-  invoice_printer_server!
-  minitest
-  pdf-inspector
-  rack-test
-  rake (>= 10.0)
-
-BUNDLED WITH
-   2.5.15