diff --git a/.github/pull_request_template.md b/.github/pull_request_template.md
index d25908ef..c0ed35fc 100644
--- a/.github/pull_request_template.md
+++ b/.github/pull_request_template.md
@@ -20,6 +20,14 @@ _Remove the irrelevant one:_
 
 _Please state how this was tested:_
 
+
+
+_Please tick which platforms this change was tested on:_
+
+- [ ] Windows
+- [ ] macOS
+- [ ] Linux
+
 ## Checklist
 
 _Please ensure all are ticked (and actually done):_
diff --git a/README.md b/README.md
index ffd4ab35..01e0be51 100644
--- a/README.md
+++ b/README.md
@@ -134,7 +134,7 @@ Run using `btm`.
 
 - `-s`, `--show_disabled_data` will show data entries in the graph legends even if the lines for that entry are disabled.
 
-- `-C`, `--config` takes in a file path leading to a TOML file.
+- `-C`, `--config` takes in a file path leading to a TOML file. If doesn't exist, creates one.
 
 - `-b`, `--basic` will enable basic mode, removing all graphs from the main interface and condensing data.
 
diff --git a/docs/config.md b/docs/config.md
index 08e171bf..e18db307 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -38,7 +38,7 @@ Note some colours may not be compatible with the terminal you are using. For exa
 
 ## Default config locations
 
-bottom will check specific locations by default for a config file.
+bottom will check specific locations by default for a config file. If no file is found, it will be created.
 
 - For Unix-based systems: `$HOME/.config/bottom/bottom.toml`.
 - For Windows: `{FOLDERID_RoamingAppData}\bottom\bottom.toml` (for example, `C:\Users\Clement\AppData\Roaming\bottom\bottom.toml`).
diff --git a/src/constants.rs b/src/constants.rs
index f00d0aa6..3ccc7b32 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -56,3 +56,95 @@ pub const SEARCH_HELP_TEXT: [&str; 13] = [
     "Alt-w/F2       Toggle whether to match the whole word\n",
     "Alt-r/F3       Toggle whether to use regex\n",
 ];
+
+pub const DEFAULT_CONFIG_CONTENT: &str = r##"
+# This is a default config file for bottom.  All of the settings are commented
+# out by default; if you wish to change them uncomment and modify as you see
+# fit.
+
+# This group of options represents a command-line flag/option.  Flags explicitly
+# added when running (ie: btm -a) will override this config file if an option
+# is also set here.
+[flags]
+
+#avg_cpu = true
+#dot_marker = false
+#rate = 1000
+#left_legend = false
+#current_usage = false
+#group_processes = false
+#case_sensitive = false
+#whole_word = true
+#regex = true
+#show_disabled_data = true
+
+# Defaults to Celsius.  Temperature is one of:
+#temperature_type = "k"
+#temperature_type = "f"
+#temperature_type = "c"
+#temperature_type = "kelvin"
+#temperature_type = "fahrenheit"
+#temperature_type = "celsius"
+
+# Defaults to processes.  Default widget is one of:
+#default_widget = "cpu_default"
+#default_widget = "memory_default"
+#default_widget = "disk_default"
+#default_widget = "temperature_default"
+#default_widget = "network_default"
+#default_widget = "process_default"
+
+
+# These are all the components that support custom theming.  Currently, it only
+# supports taking in a string representing a hex colour.  Note that colour support
+# will, at the end of the day, depend on terminal support - for example, the
+# macOS default Terminal does NOT like custom colours and it will glitch out.
+#
+# The default options here are based on gruvbox: https://github.com/morhetz/gruvbox
+[colors]
+
+# Represents the colour of table headers (processes, CPU, disks, temperature).
+#table_header_color="#458588"
+
+# Represents the colour of the label each widget has.
+#widget_title_color="#cc241d"
+
+# Represents the average CPU color
+#avg_cpu_color="#d3869b"
+
+# Represents the colour the core will use in the CPU legend and graph.
+#cpu_core_colors=["#cc241d", "#98971a"]
+
+# Represents the colour RAM will use in the memory legend and graph.
+#ram_color="#fb4934"
+
+# Represents the colour SWAP will use in the memory legend and graph.
+#swap_color="#fabd2f"
+
+# Represents the colour rx will use in the network legend and graph.
+#rx_color="#458588"
+
+# Represents the colour tx will use in the network legend and graph.
+#tx_color="#689d6a"
+
+# Represents the colour of the border of unselected widgets.
+#border_color="#ebdbb2"
+
+# Represents the colour of the border of selected widgets.
+#highlighted_border_color="#fe8019"
+
+# Represents the colour of most text.
+#text_color="#ebdbb2"
+
+# Represents the colour of text that is selected.
+#selected_text_color="#282828"
+
+# Represents the background colour of text that is selected.
+#selected_bg_color="#458588"
+
+# Represents the colour of the lines and text of the graph.
+#graph_color="#ebdbb2"
+
+# Represents the cursor's colour.
+#cursor_color="#458588"
+"##;
diff --git a/src/main.rs b/src/main.rs
index e1d6a727..04451540 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,7 +6,7 @@ extern crate clap;
 extern crate futures;
 #[macro_use]
 extern crate lazy_static;
-#[macro_use]
+#[macro_use]CEvent
 extern crate log;
 
 use std::{
@@ -79,7 +79,7 @@ fn get_matches() -> clap::ArgMatches<'static> {
 		(@arg RATE_MILLIS: -r --rate +takes_value "Sets a refresh rate in milliseconds; the minimum is 250ms, defaults to 1000ms.  Smaller values may take more resources.")
 		(@arg LEFT_LEGEND: -l --left_legend "Puts external chart legends on the left side rather than the default right side.")
 		(@arg USE_CURR_USAGE: -u --current_usage "Within Linux, sets a process' CPU usage to be based on the total current CPU usage, rather than assuming 100% usage.")
-		(@arg CONFIG_LOCATION: -C --config +takes_value "Sets the location of the config file.  Expects a config file in the TOML format.")
+		(@arg CONFIG_LOCATION: -C --config +takes_value "Sets the location of the config file.  Expects a config file in the TOML format. If it doesn't exist, one is created.")
 		(@arg BASIC_MODE: -b --basic "Hides graphs and uses a more basic look")
 		(@arg GROUP_PROCESSES: -g --group "Groups processes with the same name together on launch.")
 		(@arg CASE_SENSITIVE: -S --case_sensitive "Match case when searching by default.")
@@ -392,32 +392,250 @@ fn create_logger() -> error::Result<()> {
 }
 
 fn create_config(flag_config_location: Option<&str>) -> error::Result<Config> {
-    use std::ffi::OsString;
-    let config_path = if let Some(conf_loc) = flag_config_location {
-        OsString::from(conf_loc)
-    } else if cfg!(target_os = "windows") {
-        if let Some(home_path) = dirs::config_dir() {
-            let mut path = home_path;
-            path.push(DEFAULT_WINDOWS_CONFIG_FILE_PATH);
-            path.into_os_string()
-        } else {
-            OsString::new()
-        }
-    } else if let Some(home_path) = dirs::home_dir() {
-        let mut path = home_path;
-        path.push(DEFAULT_UNIX_CONFIG_FILE_PATH);
-        path.into_os_string()
-    } else {
-        OsString::new()
-    };
+	use std::{ffi::OsString, fs};
+	let config_path = if let Some(conf_loc) = flag_config_location {
+		OsString::from(conf_loc)
+	} else if cfg!(target_os = "windows") {
+		if let Some(home_path) = dirs::config_dir() {
+			let mut path = home_path;
+			path.push(DEFAULT_WINDOWS_CONFIG_FILE_PATH);
+			path.into_os_string()
+		} else {
+			OsString::new()
+		}
+	} else if let Some(home_path) = dirs::home_dir() {
+		let mut path = home_path;
+		path.push(DEFAULT_UNIX_CONFIG_FILE_PATH);
+		path.into_os_string()
+	} else {
+		OsString::new()
+	};
 
-    let path = std::path::Path::new(&config_path);
+	let path = std::path::Path::new(&config_path);
 
-    if let Ok(config_str) = std::fs::read_to_string(path) {
-        Ok(toml::from_str(config_str.as_str())?)
-    } else {
-        Ok(Config::default())
-    }
+	if let Ok(config_string) = fs::read_to_string(path) {
+		Ok(toml::from_str(config_string.as_str())?)
+	} else {
+		if let Some(parent_path) = path.parent() {
+			fs::create_dir_all(parent_path)?;
+		}
+		fs::File::create(path)?.write_all(DEFAULT_CONFIG_CONTENT.as_bytes())?;
+		Ok(toml::from_str(DEFAULT_CONFIG_CONTENT)?)
+	}
+}
+
+fn get_update_rate_in_milliseconds(
+	update_rate: &Option<&str>, config: &Config,
+) -> error::Result<u128> {
+	let update_rate_in_milliseconds = if let Some(update_rate) = update_rate {
+		update_rate.parse::<u128>()?
+	} else if let Some(flags) = &config.flags {
+		if let Some(rate) = flags.rate {
+			rate as u128
+		} else {
+			constants::DEFAULT_REFRESH_RATE_IN_MILLISECONDS
+		}
+	} else {
+		constants::DEFAULT_REFRESH_RATE_IN_MILLISECONDS
+	};
+
+	if update_rate_in_milliseconds < 250 {
+		return Err(BottomError::InvalidArg(
+			"Please set your update rate to be greater than 250 milliseconds.".to_string(),
+		));
+	} else if update_rate_in_milliseconds > u128::from(std::u64::MAX) {
+		return Err(BottomError::InvalidArg(
+			"Please set your update rate to be less than unsigned INT_MAX.".to_string(),
+		));
+	}
+
+	Ok(update_rate_in_milliseconds)
+}
+
+fn get_temperature_option(
+	matches: &clap::ArgMatches<'static>, config: &Config,
+) -> error::Result<data_harvester::temperature::TemperatureType> {
+	if matches.is_present("FAHRENHEIT") {
+		return Ok(data_harvester::temperature::TemperatureType::Fahrenheit);
+	} else if matches.is_present("KELVIN") {
+		return Ok(data_harvester::temperature::TemperatureType::Kelvin);
+	} else if matches.is_present("CELSIUS") {
+		return Ok(data_harvester::temperature::TemperatureType::Celsius);
+	} else if let Some(flags) = &config.flags {
+		if let Some(temp_type) = &flags.temperature_type {
+			// Give lowest priority to config.
+			return match temp_type.as_str() {
+				"fahrenheit" | "f" => {
+					Ok(data_harvester::temperature::TemperatureType::Fahrenheit)
+				}
+				"kelvin" | "k" => {
+					Ok(data_harvester::temperature::TemperatureType::Kelvin)
+				}
+				"celsius" | "c" => {
+					Ok(data_harvester::temperature::TemperatureType::Celsius)
+				}
+				_ => {
+					Err(BottomError::ConfigError(
+						"Invalid temperature type.  Please have the value be of the form \
+						 <kelvin|k|celsius|c|fahrenheit|f>"
+							.to_string(),
+					))
+				}
+			}
+		}
+	}
+	Ok(data_harvester::temperature::TemperatureType::Celsius)
+}
+
+fn get_avg_cpu_option(matches: &clap::ArgMatches<'static>, config: &Config) -> bool {
+	if matches.is_present("AVG_CPU") {
+		return true;
+	} else if let Some(flags) = &config.flags {
+		if let Some(avg_cpu) = flags.avg_cpu {
+			return avg_cpu;
+		}
+	}
+
+	false
+}
+
+fn get_use_dot_option(matches: &clap::ArgMatches<'static>, config: &Config) -> bool {
+	if matches.is_present("DOT_MARKER") {
+		return true;
+	} else if let Some(flags) = &config.flags {
+		if let Some(dot_marker) = flags.dot_marker {
+			return dot_marker;
+		}
+	}
+	false
+}
+
+fn get_use_left_legend_option(matches: &clap::ArgMatches<'static>, config: &Config) -> bool {
+	if matches.is_present("LEFT_LEGEND") {
+		return true;
+	} else if let Some(flags) = &config.flags {
+		if let Some(left_legend) = flags.left_legend {
+			return left_legend;
+		}
+	}
+
+	false
+}
+
+fn get_use_current_cpu_total_option(matches: &clap::ArgMatches<'static>, config: &Config) -> bool {
+	if matches.is_present("USE_CURR_USAGE") {
+		return true;
+	} else if let Some(flags) = &config.flags {
+		if let Some(current_usage) = flags.current_usage {
+			return current_usage;
+		}
+	}
+
+	false
+}
+
+fn get_show_disabled_data_option(matches: &clap::ArgMatches<'static>, config: &Config) -> bool {
+	if matches.is_present("SHOW_DISABLED_DATA") {
+		return true;
+	} else if let Some(flags) = &config.flags {
+		if let Some(show_disabled_data) = flags.show_disabled_data {
+			return show_disabled_data;
+		}
+	}
+
+	false
+}
+
+fn enable_app_grouping(matches: &clap::ArgMatches<'static>, config: &Config, app: &mut App) {
+	if matches.is_present("GROUP_PROCESSES") {
+		app.toggle_grouping();
+	} else if let Some(flags) = &config.flags {
+		if let Some(grouping) = flags.group_processes {
+			if grouping {
+				app.toggle_grouping();
+			}
+		}
+	}
+}
+
+fn enable_app_case_sensitive(matches: &clap::ArgMatches<'static>, config: &Config, app: &mut App) {
+	if matches.is_present("CASE_SENSITIVE") {
+		app.process_search_state.search_toggle_ignore_case();
+	} else if let Some(flags) = &config.flags {
+		if let Some(case_sensitive) = flags.case_sensitive {
+			if case_sensitive {
+				app.process_search_state.search_toggle_ignore_case();
+			}
+		}
+	}
+}
+
+fn enable_app_match_whole_word(
+	matches: &clap::ArgMatches<'static>, config: &Config, app: &mut App,
+) {
+	if matches.is_present("WHOLE_WORD") {
+		app.process_search_state.search_toggle_whole_word();
+	} else if let Some(flags) = &config.flags {
+		if let Some(whole_word) = flags.whole_word {
+			if whole_word {
+				app.process_search_state.search_toggle_whole_word();
+			}
+		}
+	}
+}
+
+fn enable_app_use_regex(matches: &clap::ArgMatches<'static>, config: &Config, app: &mut App) {
+	if matches.is_present("REGEX_DEFAULT") {
+		app.process_search_state.search_toggle_regex();
+	} else if let Some(flags) = &config.flags {
+		if let Some(regex) = flags.regex {
+			if regex {
+				app.process_search_state.search_toggle_regex();
+			}
+		}
+	}
+}
+
+fn get_default_widget(matches: &clap::ArgMatches<'static>, config: &Config) -> app::WidgetPosition {
+	if matches.is_present("CPU_WIDGET") {
+		return app::WidgetPosition::Cpu;
+	} else if matches.is_present("MEM_WIDGET") {
+		return app::WidgetPosition::Mem;
+	} else if matches.is_present("DISK_WIDGET") {
+		return app::WidgetPosition::Disk;
+	} else if matches.is_present("TEMP_WIDGET") {
+		return app::WidgetPosition::Temp;
+	} else if matches.is_present("NET_WIDGET") {
+		return app::WidgetPosition::Network;
+	} else if matches.is_present("PROC_WIDGET") {
+		return app::WidgetPosition::Process;
+	} else if let Some(flags) = &config.flags {
+		if let Some(default_widget) = &flags.default_widget {
+			match default_widget.as_str() {
+				"cpu_default" => {
+					return app::WidgetPosition::Cpu;
+				}
+				"memory_default" => {
+					return app::WidgetPosition::Mem;
+				}
+				"processes_default" => {
+					return app::WidgetPosition::Process;
+				}
+				"network_default" => {
+					return app::WidgetPosition::Network;
+				}
+				"temperature_default" => {
+					return app::WidgetPosition::Temp;
+				}
+				"disk_default" => {
+					return app::WidgetPosition::Disk;
+				}
+				_ => {}
+			}
+		}
+	}
+
+	app::WidgetPosition::Process
 }
 
 fn try_drawing(