diff --git a/mix.exs b/mix.exs
index f0b64ba..8cc696b 100644
--- a/mix.exs
+++ b/mix.exs
@@ -49,7 +49,6 @@ defmodule Diff.MixProject do
       {:makeup_elixir, "~> 1.0"},
       {:makeup_erlang, "~> 1.0"},
       {:makeup_gleam, "~> 1.0"},
-      {:makeup_syntect, "~> 0.1"},
       {:mox, "~> 1.0", only: :test},
       {:phoenix_html, "~> 4.0"},
       {:phoenix_html_helpers, "~> 1.0"},
diff --git a/mix.lock b/mix.lock
index 702f01e..fad5a88 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,7 +1,6 @@
 %{
   "bandit": {:hex, :bandit, "1.11.1", "1eb33123cc3c17ae0c3447874eb83399ee530f960c39711ed240342fbd4865fa", [:mix], [{:hpax, "~> 1.0", [hex: :hpax, repo: "hexpm", optional: false]}, {:plug, "~> 1.18", [hex: :plug, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}, {:thousand_island, "~> 1.0", [hex: :thousand_island, repo: "hexpm", optional: false]}, {:websock, "~> 0.5", [hex: :websock, repo: "hexpm", optional: false]}], "hexpm", "d4401016df9abbc6dcd325c0b78b2b193e7c7c96bb68f31e576112be025d84a5"},
   "bypass": {:hex, :bypass, "2.1.0", "909782781bf8e20ee86a9cabde36b259d44af8b9f38756173e8f5e2e1fabb9b1", [:mix], [{:plug, "~> 1.7", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 2.0", [hex: :plug_cowboy, repo: "hexpm", optional: false]}, {:ranch, "~> 1.3", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "d9b5df8fa5b7a6efa08384e9bbecfe4ce61c77d28a4282f79e02f1ef78d96b80"},
-  "castore": {:hex, :castore, "1.0.19", "6903cabdfd9d1af46454126e7c8385186659dd33ecfb74a885cae52221ad6109", [:mix], [], "hexpm", "3669e6cab13f54c2df26b3e6833745d647f35b6e30d8ddd5975df0d5c842ca98"},
   "cc_precompiler": {:hex, :cc_precompiler, "0.1.11", "8c844d0b9fb98a3edea067f94f616b3f6b29b959b6b3bf25fee94ffe34364768", [:mix], [{:elixir_make, "~> 0.7", [hex: :elixir_make, repo: "hexpm", optional: false]}], "hexpm", "3427232caf0835f94680e5bcf082408a70b48ad68a5f5c0b02a3bea9f3a075b9"},
   "circular_buffer": {:hex, :circular_buffer, "1.0.1", "01f0e3d5fe945080692cf6521c0988e9dbb5dc312831cefe77e5b63a4e658160", [:mix], [], "hexpm", "7d4ece3137d49c1f8dd0b3e0aa7c484f4d83a0be5d4b516c282085c1d5f2d7b9"},
   "cowboy": {:hex, :cowboy, "2.15.0", "9cfe86ed7117bf045e10adbedb0170af7be57f2a3637e7be143433d8dd267396", [:make, :rebar3], [{:cowlib, ">= 2.16.0 and < 3.0.0", [hex: :cowlib, repo: "hexpm", optional: false]}, {:ranch, ">= 1.8.0 and < 3.0.0", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "179fb65140fb440a17b767ad53b755081506f9596c4db5c49c0396d8c8643668"},
@@ -27,7 +26,6 @@
   "makeup_elixir": {:hex, :makeup_elixir, "1.0.1", "e928a4f984e795e41e3abd27bfc09f51db16ab8ba1aebdba2b3a575437efafc2", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.2.3 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "7284900d412a3e5cfd97fdaed4f5ed389b8f2b4cb49efc0eb3bd10e2febf9507"},
   "makeup_erlang": {:hex, :makeup_erlang, "1.1.0", "835f7e60792e08824cda445639555d7bf1bbbddb1b60b306e33cb6f6db24dc74", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "1cd6780fb1dd1a03979abaed0fe82712b0625118fd5257d3ebbf73f960c73c3c"},
   "makeup_gleam": {:hex, :makeup_gleam, "1.0.0", "c4032ef68d5f3abff3d3837cdefc293be727e718507813b13b501100b151420e", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "cf4b1dea482dd319679d009cc057db0ca2f14c8e0451ee307575b54eae00afda"},
-  "makeup_syntect": {:hex, :makeup_syntect, "0.1.4", "e1230c9e0513c667b226b21c83eb182e1ab581f65af9441edab1f9ac626acba6", [:mix], [{:makeup, "~> 1.2", [hex: :makeup, repo: "hexpm", optional: false]}, {:rustler, "~> 0.37.1", [hex: :rustler, repo: "hexpm", optional: true]}, {:rustler_precompiled, "~> 0.8.2", [hex: :rustler_precompiled, repo: "hexpm", optional: false]}], "hexpm", "5b624a434d9665786b9a352a5f3502b6c98e1996ede9936b20035ec140daef70"},
   "mime": {:hex, :mime, "2.0.7", "b8d739037be7cd402aee1ba0306edfdef982687ee7e9859bee6198c1e7e2f128", [:mix], [], "hexpm", "6171188e399ee16023ffc5b76ce445eb6d9672e2e241d2df6050f3c771e80ccd"},
   "mint": {:hex, :mint, "1.8.0", "b964eaf4416f2dee2ba88968d52239fca5621b0402b9c95f55a08eb9d74803e9", [:mix], [{:castore, "~> 0.1.0 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:hpax, "~> 0.1.1 or ~> 0.2.0 or ~> 1.0", [hex: :hpax, repo: "hexpm", optional: false]}], "hexpm", "f3c572c11355eccf00f22275e9b42463bc17bd28db13be1e28f8e0bb4adbc849"},
   "mox": {:hex, :mox, "1.2.0", "a2cd96b4b80a3883e3100a221e8adc1b98e4c3a332a8fc434c39526babafd5b3", [:mix], [{:nimble_ownership, "~> 1.0", [hex: :nimble_ownership, repo: "hexpm", optional: false]}], "hexpm", "c7b92b3cc69ee24a7eeeaf944cd7be22013c52fcb580c1f33f50845ec821089a"},
@@ -48,7 +46,6 @@
   "plug_crypto": {:hex, :plug_crypto, "2.1.1", "19bda8184399cb24afa10be734f84a16ea0a2bc65054e23a62bb10f06bc89491", [:mix], [], "hexpm", "6470bce6ffe41c8bd497612ffde1a7e4af67f36a15eea5f921af71cf3e11247c"},
   "ranch": {:hex, :ranch, "1.8.1", "208169e65292ac5d333d6cdbad49388c1ae198136e4697ae2f474697140f201c", [:make, :rebar3], [], "hexpm", "aed58910f4e21deea992a67bf51632b6d60114895eb03bb392bb733064594dd0"},
   "req": {:hex, :req, "0.5.17", "0096ddd5b0ed6f576a03dde4b158a0c727215b15d2795e59e0916c6971066ede", [:mix], [{:brotli, "~> 0.3.1", [hex: :brotli, repo: "hexpm", optional: true]}, {:ezstd, "~> 1.0", [hex: :ezstd, repo: "hexpm", optional: true]}, {:finch, "~> 0.17", [hex: :finch, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:mime, "~> 2.0.6 or ~> 2.1", [hex: :mime, repo: "hexpm", optional: false]}, {:nimble_csv, "~> 1.0", [hex: :nimble_csv, repo: "hexpm", optional: true]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "0b8bc6ffdfebbc07968e59d3ff96d52f2202d0536f10fef4dc11dc02a2a43e39"},
-  "rustler_precompiled": {:hex, :rustler_precompiled, "0.8.4", "700a878312acfac79fb6c572bb8b57f5aae05fe1cf70d34b5974850bbf2c05bf", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: false]}, {:rustler, "~> 0.23", [hex: :rustler, repo: "hexpm", optional: true]}], "hexpm", "3b33d99b540b15f142ba47944f7a163a25069f6d608783c321029bc1ffb09514"},
   "sentry": {:hex, :sentry, "13.1.0", "ad5c2c45dfa8c5b9b136b365f1e990dbca4809bb50a5a61938146b95d748424a", [:mix], [{:finch, "~> 0.21", [hex: :finch, repo: "hexpm", optional: true]}, {:hackney, "~> 1.8", [hex: :hackney, repo: "hexpm", optional: true]}, {:igniter, "~> 0.5", [hex: :igniter, repo: "hexpm", optional: true]}, {:jason, "~> 1.1", [hex: :jason, repo: "hexpm", optional: true]}, {:nimble_options, "~> 1.0", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:nimble_ownership, "~> 1.0", [hex: :nimble_ownership, repo: "hexpm", optional: false]}, {:opentelemetry, ">= 0.0.0", [hex: :opentelemetry, repo: "hexpm", optional: true]}, {:opentelemetry_api, ">= 0.0.0", [hex: :opentelemetry_api, repo: "hexpm", optional: true]}, {:opentelemetry_exporter, ">= 0.0.0", [hex: :opentelemetry_exporter, repo: "hexpm", optional: true]}, {:opentelemetry_semantic_conventions, ">= 0.0.0", [hex: :opentelemetry_semantic_conventions, repo: "hexpm", optional: true]}, {:phoenix, "~> 1.6", [hex: :phoenix, repo: "hexpm", optional: true]}, {:phoenix_live_view, "~> 0.20 or ~> 1.0", [hex: :phoenix_live_view, repo: "hexpm", optional: true]}, {:plug, "~> 1.6", [hex: :plug, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: true]}], "hexpm", "9e56a6415a3a243c2ad02cf55ef1133d54addbe743eb7909bc66d6f517300bdf"},
   "tailwind": {:hex, :tailwind, "0.4.1", "e7bcc222fe96a1e55f948e76d13dd84a1a7653fb051d2a167135db3b4b08d3e9", [:mix], [], "hexpm", "6249d4f9819052911120dbdbe9e532e6bd64ea23476056adb7f730aa25c220d1"},
   "telemetry": {:hex, :telemetry, "1.4.2", "a0cb522801dffb1c49fe6e30561badffc7b6d0e180db1300df759faa22062855", [:rebar3], [], "hexpm", "928f6495066506077862c0d1646609eed891a4326bee3126ba54b60af61febb1"},
diff --git a/test/diff_web/live/components/diff_component_test.exs b/test/diff_web/live/components/diff_component_test.exs
index 7e9695c..7b194b8 100644
--- a/test/diff_web/live/components/diff_component_test.exs
+++ b/test/diff_web/live/components/diff_component_test.exs
@@ -117,5 +117,32 @@ defmodule DiffWeb.DiffComponentTest do
       assert html =~ "removed"
       assert html =~ "added"
     end
+
+    test "highlights BEAM-language source" do
+      diff = %GitDiff.Patch{
+        from: "lib/app.ex",
+        to: "lib/app.ex",
+        chunks: [chunk([line(text: " x = 1")])]
+      }
+
+      html = render_component(diff, "diff-ex")
+
+      # Highlighting wraps each token in its own <span>, so the source text is
+      # no longer contiguous in the output.
+      refute html =~ "x = 1"
+    end
+
+    test "renders non-BEAM files as plain text" do
+      diff = %GitDiff.Patch{
+        from: "config/data.json",
+        to: "config/data.json",
+        chunks: [chunk([line(text: " [1, 2, 3]")])]
+      }
+
+      html = render_component(diff, "diff-json")
+
+      # JSON is not highlighted, so the contents stay intact.
+      assert html =~ "[1, 2, 3]"
+    end
   end
 end