diff --git a/src/command.rs b/src/command.rs
index b6d03b5..e557dd0 100644
--- a/src/command.rs
+++ b/src/command.rs
@@ -1,8 +1,15 @@
 use std::collections::BTreeMap;
 use std::fmt;
 
+use crate::{error::OptionsError, parameter_range::get_parameterized_commands};
+
+use clap::ArgMatches;
+
+use crate::tokenize::tokenize;
 use crate::types::ParameterValue;
 
+use anyhow::{bail, Result};
+
 /// A command that should be benchmarked.
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Command<'a> {
@@ -82,6 +89,125 @@ impl<'a> Command<'a> {
     }
 }
 
+/// Build the commands to benchmark
+pub fn build_commands(matches: &ArgMatches) -> Result<Vec<Command>> {
+    let command_names = matches.values_of("command-name");
+    let command_strings = matches.values_of("command").unwrap();
+
+    if let Some(args) = matches.values_of("parameter-scan") {
+        let step_size = matches.value_of("parameter-step-size");
+        Ok(get_parameterized_commands(
+            command_names,
+            command_strings,
+            args,
+            step_size,
+        )?)
+    } else if let Some(args) = matches.values_of("parameter-list") {
+        let command_names = command_names.map_or(vec![], |names| names.collect::<Vec<&str>>());
+
+        let args: Vec<_> = args.collect();
+        let param_names_and_values: Vec<(&str, Vec<String>)> = args
+            .chunks_exact(2)
+            .map(|pair| {
+                let name = pair[0];
+                let list_str = pair[1];
+                (name, tokenize(list_str))
+            })
+            .collect();
+        {
+            let dupes = find_dupes(param_names_and_values.iter().map(|(name, _)| *name));
+            if !dupes.is_empty() {
+                bail!("Duplicate parameter names: {}", &dupes.join(", "));
+            }
+        }
+        let command_list = command_strings.collect::<Vec<&str>>();
+
+        let dimensions: Vec<usize> = std::iter::once(command_list.len())
+            .chain(
+                param_names_and_values
+                    .iter()
+                    .map(|(_, values)| values.len()),
+            )
+            .collect();
+        let param_space_size = dimensions.iter().product();
+        if param_space_size == 0 {
+            return Ok(Vec::new());
+        }
+
+        // `--command-name` should appear exactly once or exactly B times,
+        // where B is the total number of benchmarks.
+        let command_name_count = command_names.len();
+        if command_name_count > 1 && command_name_count != param_space_size {
+            return Err(OptionsError::UnexpectedCommandNameCount(
+                command_name_count,
+                param_space_size,
+            )
+            .into());
+        }
+
+        let mut i = 0;
+        let mut commands = Vec::with_capacity(param_space_size);
+        let mut index = vec![0usize; dimensions.len()];
+        'outer: loop {
+            let name = command_names
+                .get(i)
+                .or_else(|| command_names.get(0))
+                .copied();
+            i += 1;
+
+            let (command_index, params_indices) = index.split_first().unwrap();
+            let parameters = param_names_and_values
+                .iter()
+                .zip(params_indices)
+                .map(|((name, values), i)| (*name, ParameterValue::Text(values[*i].clone())))
+                .collect();
+            commands.push(Command::new_parametrized(
+                name,
+                command_list[*command_index],
+                parameters,
+            ));
+
+            // Increment index, exiting loop on overflow.
+            for (i, n) in index.iter_mut().zip(dimensions.iter()) {
+                *i += 1;
+                if *i < *n {
+                    continue 'outer;
+                } else {
+                    *i = 0;
+                }
+            }
+            break 'outer;
+        }
+
+        Ok(commands)
+    } else {
+        let command_names = command_names.map_or(vec![], |names| names.collect::<Vec<&str>>());
+        if command_names.len() > command_strings.len() {
+            return Err(OptionsError::TooManyCommandNames(command_strings.len()).into());
+        }
+
+        let command_list = command_strings.collect::<Vec<&str>>();
+        let mut commands = Vec::with_capacity(command_list.len());
+        for (i, s) in command_list.iter().enumerate() {
+            commands.push(Command::new(command_names.get(i).copied(), s));
+        }
+        Ok(commands)
+    }
+}
+
+/// Finds all the strings that appear multiple times in the input iterator, returning them in
+/// sorted order. If no string appears more than once, the result is an empty vector.
+fn find_dupes<'a, I: IntoIterator<Item = &'a str>>(i: I) -> Vec<&'a str> {
+    let mut counts = BTreeMap::<&'a str, usize>::new();
+    for s in i {
+        *counts.entry(s).or_default() += 1;
+    }
+    counts
+        .into_iter()
+        .filter_map(|(k, n)| if n > 1 { Some(k) } else { None })
+        .collect()
+}
+
 #[test]
 fn test_get_shell_command_nonoverlapping() {
     let cmd = Command::new_parametrized(
@@ -113,3 +239,85 @@ impl<'a> fmt::Display for Command<'a> {
         write!(f, "{}", self.get_shell_command())
     }
 }
+
+#[test]
+fn test_build_commands_cross_product() {
+    use crate::app::get_arg_matches;
+
+    let matches = get_arg_matches(vec![
+        "hyperfine",
+        "-L",
+        "par1",
+        "a,b",
+        "-L",
+        "par2",
+        "z,y",
+        "echo {par1} {par2}",
+        "printf '%s\n' {par1} {par2}",
+    ]);
+    let result = build_commands(&matches).unwrap();
+
+    // Iteration order: command list first, then parameters in listed order (here, "par1" before
+    // "par2", which is distinct from their sorted order), with parameter values in listed order.
+    let pv = |s: &str| ParameterValue::Text(s.to_string());
+    let cmd = |cmd: usize, par1: &str, par2: &str| {
+        let expression = ["echo {par1} {par2}", "printf '%s\n' {par1} {par2}"][cmd];
+        let params = vec![("par1", pv(par1)), ("par2", pv(par2))];
+        Command::new_parametrized(None, expression, params)
+    };
+    let expected = vec![
+        cmd(0, "a", "z"),
+        cmd(1, "a", "z"),
+        cmd(0, "b", "z"),
+        cmd(1, "b", "z"),
+        cmd(0, "a", "y"),
+        cmd(1, "a", "y"),
+        cmd(0, "b", "y"),
+        cmd(1, "b", "y"),
+    ];
+    assert_eq!(result, expected);
+}
+
+#[test]
+fn test_build_parameter_list_commands() {
+    use crate::app::get_arg_matches;
+
+    let matches = get_arg_matches(vec![
+        "hyperfine",
+        "echo {foo}",
+        "--parameter-list",
+        "foo",
+        "1,2",
+        "--command-name",
+        "name-{foo}",
+    ]);
+    let commands = build_commands(&matches).unwrap();
+    assert_eq!(commands.len(), 2);
+    assert_eq!(commands[0].get_name(), "name-1");
+    assert_eq!(commands[1].get_name(), "name-2");
+    assert_eq!(commands[0].get_shell_command(), "echo 1");
+    assert_eq!(commands[1].get_shell_command(), "echo 2");
+}
+
+#[test]
+fn test_build_parameter_range_commands() {
+    use crate::app::get_arg_matches;
+    let matches = get_arg_matches(vec![
+        "hyperfine",
+        "echo {val}",
+        "--parameter-scan",
+        "val",
+        "1",
+        "2",
+        "--parameter-step-size",
+        "1",
+        "--command-name",
+        "name-{val}",
+    ]);
+    let commands = build_commands(&matches).unwrap();
+    assert_eq!(commands.len(), 2);
+    assert_eq!(commands[0].get_name(), "name-1");
+    assert_eq!(commands[1].get_name(), "name-2");
+    assert_eq!(commands[0].get_shell_command(), "echo 1");
+    assert_eq!(commands[1].get_shell_command(), "echo 2");
+}
diff --git a/src/main.rs b/src/main.rs
index 819f0e3..bacb56f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,7 +1,5 @@
-use std::collections::BTreeMap;
 use std::env;
 
-use clap::ArgMatches;
 use colored::*;
 
 pub mod app;
@@ -27,13 +25,9 @@ pub mod warnings;
 use app::get_arg_matches;
 use benchmark::{mean_shell_spawning_time, run_benchmark};
 use benchmark_result::BenchmarkResult;
-use command::Command;
-use error::OptionsError;
+use command::{build_commands, Command};
 use export::ExportManager;
 use options::{Options, OutputStyleOption};
-use parameter_range::get_parameterized_commands;
-use tokenize::tokenize;
-use types::ParameterValue;
 
 use anyhow::{bail, Result};
 
@@ -132,199 +126,3 @@ fn main() {
         }
     }
 }
-
-/// Build the commands to benchmark
-fn build_commands(matches: &ArgMatches) -> Result<Vec<Command>> {
-    let command_names = matches.values_of("command-name");
-    let command_strings = matches.values_of("command").unwrap();
-
-    if let Some(args) = matches.values_of("parameter-scan") {
-        let step_size = matches.value_of("parameter-step-size");
-        Ok(get_parameterized_commands(
-            command_names,
-            command_strings,
-            args,
-            step_size,
-        )?)
-    } else if let Some(args) = matches.values_of("parameter-list") {
-        let command_names = command_names.map_or(vec![], |names| names.collect::<Vec<&str>>());
-
-        let args: Vec<_> = args.collect();
-        let param_names_and_values: Vec<(&str, Vec<String>)> = args
-            .chunks_exact(2)
-            .map(|pair| {
-                let name = pair[0];
-                let list_str = pair[1];
-                (name, tokenize(list_str))
-            })
-            .collect();
-        {
-            let dupes = find_dupes(param_names_and_values.iter().map(|(name, _)| *name));
-            if !dupes.is_empty() {
-                bail!("Duplicate parameter names: {}", &dupes.join(", "));
-            }
-        }
-        let command_list = command_strings.collect::<Vec<&str>>();
-
-        let dimensions: Vec<usize> = std::iter::once(command_list.len())
-            .chain(
-                param_names_and_values
-                    .iter()
-                    .map(|(_, values)| values.len()),
-            )
-            .collect();
-        let param_space_size = dimensions.iter().product();
-        if param_space_size == 0 {
-            return Ok(Vec::new());
-        }
-
-        // `--command-name` should appear exactly once or exactly B times,
-        // where B is the total number of benchmarks.
-        let command_name_count = command_names.len();
-        if command_name_count > 1 && command_name_count != param_space_size {
-            return Err(OptionsError::UnexpectedCommandNameCount(
-                command_name_count,
-                param_space_size,
-            )
-            .into());
-        }
-
-        let mut i = 0;
-        let mut commands = Vec::with_capacity(param_space_size);
-        let mut index = vec![0usize; dimensions.len()];
-        'outer: loop {
-            let name = command_names
-                .get(i)
-                .or_else(|| command_names.get(0))
-                .copied();
-            i += 1;
-
-            let (command_index, params_indices) = index.split_first().unwrap();
-            let parameters = param_names_and_values
-                .iter()
-                .zip(params_indices)
-                .map(|((name, values), i)| (*name, ParameterValue::Text(values[*i].clone())))
-                .collect();
-            commands.push(Command::new_parametrized(
-                name,
-                command_list[*command_index],
-                parameters,
-            ));
-
-            // Increment index, exiting loop on overflow.
-            for (i, n) in index.iter_mut().zip(dimensions.iter()) {
-                *i += 1;
-                if *i < *n {
-                    continue 'outer;
-                } else {
-                    *i = 0;
-                }
-            }
-            break 'outer;
-        }
-
-        Ok(commands)
-    } else {
-        let command_names = command_names.map_or(vec![], |names| names.collect::<Vec<&str>>());
-        if command_names.len() > command_strings.len() {
-            return Err(OptionsError::TooManyCommandNames(command_strings.len()).into());
-        }
-
-        let command_list = command_strings.collect::<Vec<&str>>();
-        let mut commands = Vec::with_capacity(command_list.len());
-        for (i, s) in command_list.iter().enumerate() {
-            commands.push(Command::new(command_names.get(i).copied(), s));
-        }
-        Ok(commands)
-    }
-}
-
-/// Finds all the strings that appear multiple times in the input iterator, returning them in
-/// sorted order. If no string appears more than once, the result is an empty vector.
-fn find_dupes<'a, I: IntoIterator<Item = &'a str>>(i: I) -> Vec<&'a str> {
-    let mut counts = BTreeMap::<&'a str, usize>::new();
-    for s in i {
-        *counts.entry(s).or_default() += 1;
-    }
-    counts
-        .into_iter()
-        .filter_map(|(k, n)| if n > 1 { Some(k) } else { None })
-        .collect()
-}
-
-#[test]
-fn test_build_commands_cross_product() {
-    let matches = get_arg_matches(vec![
-        "hyperfine",
-        "-L",
-        "par1",
-        "a,b",
-        "-L",
-        "par2",
-        "z,y",
-        "echo {par1} {par2}",
-        "printf '%s\n' {par1} {par2}",
-    ]);
-    let result = build_commands(&matches).unwrap();
-
-    // Iteration order: command list first, then parameters in listed order (here, "par1" before
-    // "par2", which is distinct from their sorted order), with parameter values in listed order.
-    let pv = |s: &str| ParameterValue::Text(s.to_string());
-    let cmd = |cmd: usize, par1: &str, par2: &str| {
-        let expression = ["echo {par1} {par2}", "printf '%s\n' {par1} {par2}"][cmd];
-        let params = vec![("par1", pv(par1)), ("par2", pv(par2))];
-        Command::new_parametrized(None, expression, params)
-    };
-    let expected = vec![
-        cmd(0, "a", "z"),
-        cmd(1, "a", "z"),
-        cmd(0, "b", "z"),
-        cmd(1, "b", "z"),
-        cmd(0, "a", "y"),
-        cmd(1, "a", "y"),
-        cmd(0, "b", "y"),
-        cmd(1, "b", "y"),
-    ];
-    assert_eq!(result, expected);
-}
-
-#[test]
-fn test_build_parameter_list_commands() {
-    let matches = get_arg_matches(vec![
-        "hyperfine",
-        "echo {foo}",
-        "--parameter-list",
-        "foo",
-        "1,2",
-        "--command-name",
-        "name-{foo}",
-    ]);
-    let commands = build_commands(&matches).unwrap();
-    assert_eq!(commands.len(), 2);
-    assert_eq!(commands[0].get_name(), "name-1");
-    assert_eq!(commands[1].get_name(), "name-2");
-    assert_eq!(commands[0].get_shell_command(), "echo 1");
-    assert_eq!(commands[1].get_shell_command(), "echo 2");
-}
-
-#[test]
-fn test_build_parameter_range_commands() {
-    let matches = get_arg_matches(vec![
-        "hyperfine",
-        "echo {val}",
-        "--parameter-scan",
-        "val",
-        "1",
-        "2",
-        "--parameter-step-size",
-        "1",
-        "--command-name",
-        "name-{val}",
-    ]);
-    let commands = build_commands(&matches).unwrap();
-    assert_eq!(commands.len(), 2);
-    assert_eq!(commands[0].get_name(), "name-1");
-    assert_eq!(commands[1].get_name(), "name-2");
-    assert_eq!(commands[0].get_shell_command(), "echo 1");
-    assert_eq!(commands[1].get_shell_command(), "echo 2");
-}