diff --git a/poetry.lock b/poetry.lock
index 718296f..f2f59a5 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -2424,4 +2424,4 @@ watchmedo = ["PyYAML (>=3.10)"]
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.10"
-content-hash = "96afc722df2e1cdb0f1294ebc86f88e881dce618e788ed799acc210ccb07ef2a"
+content-hash = "244156c52b101f607c0e6c6ae14a61a39f59aa61f6a705a39741c658beb3c48d"
diff --git a/pyproject.toml b/pyproject.toml
index eabc4b6..ce60304 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -42,6 +42,7 @@ mkdocstrings = { extras = ["python"], version = "^0.20.0" }
 # textual = "^0.51.0"
 textual = { extras = ["syntax"], version = "^0.51.0" }
 textual-plotext = "^0.2.1"
+tree-sitter-languages = "==1.10.2"  # Pin for security, to avoid re-auditing
 
 [tool.poetry.group.plot.dependencies]
 matplotlib = "^3.8.3"
diff --git a/src/hpc_multibench/tui/bash_highlights.py b/src/hpc_multibench/tui/bash_highlights.py
new file mode 100755
index 0000000..8dae164
--- /dev/null
+++ b/src/hpc_multibench/tui/bash_highlights.py
@@ -0,0 +1,150 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+A tree-sitter query for highlighting bash.
+
+Query string derived from:
+https://github.com/nvim-treesitter/nvim-treesitter/blob/f95ffd09ed35880c3a46ad2b968df361fa592a76/queries/bash/highlights.scm
+
+Which is aligned with the approach taken for Textual builtin languages, for example:
+https://github.com/Textualize/textual/blob/main/src/textual/tree-sitter/highlights/python.scm
+"""
+
+BASH_HIGHLIGHTS = """
+(simple_expansion) @none
+(expansion
+  "${" @punctuation.special
+  "}" @punctuation.special) @none
+[
+ "("
+ ")"
+ "(("
+ "))"
+ "{"
+ "}"
+ "["
+ "]"
+ "[["
+ "]]"
+ ] @punctuation.bracket
+
+[
+ ";"
+ ";;"
+ (heredoc_start)
+ ] @punctuation.delimiter
+
+[
+ "$"
+] @punctuation.special
+
+[
+ ">"
+ ">>"
+ "<"
+ "<<"
+ "&"
+ "&&"
+ "|"
+ "||"
+ "="
+ "=~"
+ "=="
+ "!="
+ ] @operator
+
+[
+ (string)
+ (raw_string)
+ (ansi_c_string)
+ (heredoc_body)
+] @string @spell
+
+(variable_assignment (word) @string)
+
+[
+ "if"
+ "then"
+ "else"
+ "elif"
+ "fi"
+ "case"
+ "in"
+ "esac"
+ ] @conditional
+
+[
+ "for"
+ "do"
+ "done"
+ "while"
+ ] @repeat
+
+[
+ "declare"
+ "export"
+ "local"
+ "readonly"
+ "unset"
+ ] @keyword
+
+"function" @keyword.function
+
+(special_variable_name) @constant
+
+; trap -l
+((word) @constant.builtin
+ (#match? @constant.builtin "^SIG(HUP|INT|QUIT|ILL|TRAP|ABRT|BUS|FPE|KILL|USR[12]|SEGV|PIPE|ALRM|TERM|STKFLT|CHLD|CONT|STOP|TSTP|TT(IN|OU)|URG|XCPU|XFSZ|VTALRM|PROF|WINCH|IO|PWR|SYS|RTMIN([+]([1-9]|1[0-5]))?|RTMAX(-([1-9]|1[0-4]))?)$"))
+
+((word) @boolean
+  (#match? @boolean "^(true|false)$"))
+
+(comment) @comment @spell
+(test_operator) @string
+
+(command_substitution
+  [ "$(" ")" ] @punctuation.bracket)
+
+(process_substitution
+  [ "<(" ")" ] @punctuation.bracket)
+
+
+(function_definition
+  name: (word) @function)
+
+(command_name (word) @function.call)
+
+((command_name (word) @function.builtin)
+ (#any-of? @function.builtin
+    "alias" "cd" "clear" "echo" "eval" "exit" "getopts" "popd"
+    "pushd" "return" "set" "shift" "shopt" "source" "test"))
+
+(command
+  argument: [
+             (word) @parameter
+             (concatenation (word) @parameter)
+             ])
+
+((word) @number
+  (#lua-match? @number "^[0-9]+$"))
+
+(file_redirect
+  descriptor: (file_descriptor) @operator
+  destination: (word) @parameter)
+
+(expansion
+  [ "${" "}" ] @punctuation.bracket)
+
+(variable_name) @variable
+
+((variable_name) @constant
+ (#lua-match? @constant "^[A-Z][A-Z_0-9]*$"))
+
+(case_item
+  value: (word) @parameter)
+
+(regex) @string.regex
+
+((program . (comment) @preproc)
+  (#match? @preproc "^#!/"))
+"""
diff --git a/src/hpc_multibench/tui/interactive_ui.py b/src/hpc_multibench/tui/interactive_ui.py
index 514b123..8f73155 100755
--- a/src/hpc_multibench/tui/interactive_ui.py
+++ b/src/hpc_multibench/tui/interactive_ui.py
@@ -24,11 +24,13 @@
 )
 from textual.widgets.tree import TreeNode
 from textual_plotext import PlotextPlot
+from tree_sitter_languages import get_language
 
 from hpc_multibench.plot import plot_matplotlib, plot_plotext
 from hpc_multibench.run_configuration import RunConfiguration, get_queued_job_ids
 from hpc_multibench.test_bench import TestBench
 from hpc_multibench.test_plan import TestPlan
+from hpc_multibench.tui.bash_highlights import BASH_HIGHLIGHTS
 from hpc_multibench.uncertainties import UFloat
 from hpc_multibench.yaml_model import (
     BarChartModel,
@@ -210,6 +212,7 @@ def compose(self) -> ComposeResult:
                         id="sbatch-contents",
                         read_only=True,
                         show_line_numbers=True,
+                        theme="monokai",
                     )
                 with TabPane("Metrics", id="metrics-tab"):
                     yield DataTable(id="metrics-table")
@@ -220,6 +223,10 @@ def compose(self) -> ComposeResult:
     def on_mount(self) -> None:
         """Initialise data when the application is created."""
         self.initialise_test_plan_tree()
+        self.query_one("#sbatch-contents", TextArea).register_language(
+            get_language("bash"), BASH_HIGHLIGHTS
+        )
+        self.query_one("#sbatch-contents", TextArea).language = "bash"
 
     def on_button_pressed(self, event: Button.Pressed) -> None:
         """When a button is pressed."""
@@ -397,7 +404,7 @@ def get_plot_model(
     def action_reload_test_plan(self) -> None:
         """Reload the test plan for the user interface."""
         self.test_plan = TestPlan(self.test_plan.yaml_path)
-        self.on_mount()
+        self.initialise_test_plan_tree()
         self.update_all_tabs()
 
     def action_change_plot(self, offset: int) -> None: