diff --git a/Cargo.lock b/Cargo.lock
index e06a012..30b00c9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -153,7 +153,6 @@ dependencies = [
  "indicatif 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.54 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.91 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde_derive 1.0.90 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.39 (registry+https://github.com/rust-lang/crates.io-index)",
  "statistical 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -462,6 +461,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "serde"
 version = "1.0.91"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde_derive 1.0.90 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "serde_derive"
diff --git a/Cargo.toml b/Cargo.toml
index 5fbcb1b..9395e3e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,6 +8,7 @@ name = "hyperfine"
 readme = "README.md"
 repository = "https://github.com/sharkdp/hyperfine"
 version = "1.5.0"
+edition = "2018"
 
 [dependencies]
 colored = "1.7"
@@ -16,8 +17,7 @@ statistical = "1.0"
 atty = "0.2.2"
 cfg-if = "0.1.7"
 csv = "1.0.7"
-serde = "1.0.91"
-serde_derive = "1.0.90"
+serde = { version = "1.0.91", features = ["derive"] }
 serde_json = "1.0.39"
 
 [target.'cfg(not(windows))'.dependencies]
diff --git a/src/hyperfine/app.rs b/src/hyperfine/app.rs
index 32e0921..b24d38a 100644
--- a/src/hyperfine/app.rs
+++ b/src/hyperfine/app.rs
@@ -1,6 +1,6 @@
 use atty;
 use atty::Stream;
-use clap::{App, AppSettings, Arg, ArgMatches};
+use clap::{crate_version, App, AppSettings, Arg, ArgMatches};
 use std::ffi::OsString;
 
 pub fn get_arg_matches<T>(args: T) -> ArgMatches<'static>
diff --git a/src/hyperfine/benchmark.rs b/src/hyperfine/benchmark.rs
index edd0a41..890fde5 100644
--- a/src/hyperfine/benchmark.rs
+++ b/src/hyperfine/benchmark.rs
@@ -5,17 +5,17 @@ use std::process::Stdio;
 use colored::*;
 use statistical::{mean, standard_deviation};
 
-use hyperfine::format::{format_duration, format_duration_unit};
-use hyperfine::internal::{get_progress_bar, max, min, MIN_EXECUTION_TIME};
-use hyperfine::outlier_detection::{modified_zscores, OUTLIER_THRESHOLD};
-use hyperfine::shell::execute_and_time;
-use hyperfine::timer::wallclocktimer::WallClockTimer;
-use hyperfine::timer::{TimerStart, TimerStop};
-use hyperfine::types::{
+use crate::hyperfine::format::{format_duration, format_duration_unit};
+use crate::hyperfine::internal::{get_progress_bar, max, min, MIN_EXECUTION_TIME};
+use crate::hyperfine::outlier_detection::{modified_zscores, OUTLIER_THRESHOLD};
+use crate::hyperfine::shell::execute_and_time;
+use crate::hyperfine::timer::wallclocktimer::WallClockTimer;
+use crate::hyperfine::timer::{TimerStart, TimerStop};
+use crate::hyperfine::types::{
     BenchmarkResult, CmdFailureAction, Command, HyperfineOptions, OutputStyleOption,
 };
-use hyperfine::units::Second;
-use hyperfine::warnings::Warnings;
+use crate::hyperfine::units::Second;
+use crate::hyperfine::warnings::Warnings;
 
 /// Results from timing a single shell command
 #[derive(Debug, Default, Copy, Clone)]
@@ -42,7 +42,7 @@ fn subtract_shell_spawning_time(time: Second, shell_spawning_time: Second) -> Se
 /// Run the given shell command and measure the execution time
 pub fn time_shell_command(
     shell: &str,
-    command: &Command,
+    command: &Command<'_>,
     show_output: bool,
     failure_action: CmdFailureAction,
     shell_spawning_time: Option<TimingResult>,
@@ -146,7 +146,7 @@ pub fn mean_shell_spawning_time(
 
 fn run_intermediate_command(
     shell: &str,
-    command: &Option<Command>,
+    command: &Option<Command<'_>>,
     show_output: bool,
     error_output: &'static str,
 ) -> io::Result<TimingResult> {
@@ -165,7 +165,7 @@ fn run_intermediate_command(
 /// Run the command specified by `--prepare`.
 fn run_preparation_command(
     shell: &str,
-    command: &Option<Command>,
+    command: &Option<Command<'_>>,
     show_output: bool,
 ) -> io::Result<TimingResult> {
     let error_output = "The preparation command terminated with a non-zero exit code. \
@@ -177,7 +177,7 @@ fn run_preparation_command(
 /// Run the command specified by `--cleanup`.
 fn run_cleanup_command(
     shell: &str,
-    command: &Option<Command>,
+    command: &Option<Command<'_>>,
     show_output: bool,
 ) -> io::Result<TimingResult> {
     let error_output = "The cleanup command terminated with a non-zero exit code. \
@@ -189,7 +189,7 @@ fn run_cleanup_command(
 /// Run the benchmark for a single shell command
 pub fn run_benchmark(
     num: usize,
-    cmd: &Command,
+    cmd: &Command<'_>,
     shell_spawning_time: TimingResult,
     options: &HyperfineOptions,
 ) -> io::Result<BenchmarkResult> {
diff --git a/src/hyperfine/error.rs b/src/hyperfine/error.rs
index 033cc4f..d1fe060 100644
--- a/src/hyperfine/error.rs
+++ b/src/hyperfine/error.rs
@@ -16,7 +16,7 @@ impl From<num::ParseIntError> for ParameterScanError {
 }
 
 impl fmt::Display for ParameterScanError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.description())
     }
 }
@@ -38,7 +38,7 @@ pub enum OptionsError {
 }
 
 impl fmt::Display for OptionsError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.description())
     }
 }
diff --git a/src/hyperfine/export/asciidoc.rs b/src/hyperfine/export/asciidoc.rs
index f2d053e..81d6c68 100644
--- a/src/hyperfine/export/asciidoc.rs
+++ b/src/hyperfine/export/asciidoc.rs
@@ -1,8 +1,8 @@
 use super::Exporter;
 
-use hyperfine::format::format_duration_value;
-use hyperfine::types::BenchmarkResult;
-use hyperfine::units::Unit;
+use crate::hyperfine::format::format_duration_value;
+use crate::hyperfine::types::BenchmarkResult;
+use crate::hyperfine::units::Unit;
 
 use std::io::Result;
 
diff --git a/src/hyperfine/export/csv.rs b/src/hyperfine/export/csv.rs
index 57c0bef..8b611e6 100644
--- a/src/hyperfine/export/csv.rs
+++ b/src/hyperfine/export/csv.rs
@@ -1,7 +1,7 @@
 use super::Exporter;
 
-use hyperfine::types::BenchmarkResult;
-use hyperfine::units::Unit;
+use crate::hyperfine::types::BenchmarkResult;
+use crate::hyperfine::units::Unit;
 
 use std::io::{Error, ErrorKind, Result};
 
diff --git a/src/hyperfine/export/json.rs b/src/hyperfine/export/json.rs
index 62a3f50..01da670 100644
--- a/src/hyperfine/export/json.rs
+++ b/src/hyperfine/export/json.rs
@@ -1,9 +1,10 @@
 use super::Exporter;
-use hyperfine::types::BenchmarkResult;
-use hyperfine::units::Unit;
+use crate::hyperfine::types::BenchmarkResult;
+use crate::hyperfine::units::Unit;
 
 use std::io::{Error, ErrorKind, Result};
 
+use serde::*;
 use serde_json::to_vec_pretty;
 
 #[derive(Serialize, Debug)]
diff --git a/src/hyperfine/export/markdown.rs b/src/hyperfine/export/markdown.rs
index 930b10c..4acef23 100644
--- a/src/hyperfine/export/markdown.rs
+++ b/src/hyperfine/export/markdown.rs
@@ -1,8 +1,8 @@
 use super::Exporter;
 
-use hyperfine::format::format_duration_value;
-use hyperfine::types::BenchmarkResult;
-use hyperfine::units::Unit;
+use crate::hyperfine::format::format_duration_value;
+use crate::hyperfine::types::BenchmarkResult;
+use crate::hyperfine::units::Unit;
 
 use std::io::Result;
 
diff --git a/src/hyperfine/export/mod.rs b/src/hyperfine/export/mod.rs
index f8c06fd..d6825e3 100644
--- a/src/hyperfine/export/mod.rs
+++ b/src/hyperfine/export/mod.rs
@@ -11,8 +11,8 @@ use self::markdown::MarkdownExporter;
 use std::fs::File;
 use std::io::{Result, Write};
 
-use hyperfine::types::BenchmarkResult;
-use hyperfine::units::Unit;
+use crate::hyperfine::types::BenchmarkResult;
+use crate::hyperfine::units::Unit;
 
 /// The desired form of exporter to use for a given file.
 #[derive(Clone)]
@@ -37,7 +37,7 @@ trait Exporter {
 }
 
 struct ExporterWithFilename {
-    exporter: Box<Exporter>,
+    exporter: Box<dyn Exporter>,
     filename: String,
 }
 
@@ -56,7 +56,7 @@ impl ExportManager {
 
     /// Add an additional exporter to the ExportManager
     pub fn add_exporter(&mut self, export_type: ExportType, filename: &str) {
-        let exporter: Box<Exporter> = match export_type {
+        let exporter: Box<dyn Exporter> = match export_type {
             ExportType::Asciidoc => Box::new(AsciidocExporter::default()),
             ExportType::Csv => Box::new(CsvExporter::default()),
             ExportType::Json => Box::new(JsonExporter::default()),
diff --git a/src/hyperfine/format.rs b/src/hyperfine/format.rs
index 08f0c61..1204c46 100644
--- a/src/hyperfine/format.rs
+++ b/src/hyperfine/format.rs
@@ -1,4 +1,4 @@
-use hyperfine::units::{Second, Unit};
+use crate::hyperfine::units::{Second, Unit};
 
 /// Format the given duration as a string. The output-unit can be enforced by setting `unit` to
 /// `Some(target_unit)`. If `unit` is `None`, it will be determined automatically.
diff --git a/src/hyperfine/internal.rs b/src/hyperfine/internal.rs
index 51ea152..fd8157a 100644
--- a/src/hyperfine/internal.rs
+++ b/src/hyperfine/internal.rs
@@ -1,8 +1,8 @@
 use colored::*;
 use indicatif::{ProgressBar, ProgressStyle};
 
-use hyperfine::types::{BenchmarkResult, OutputStyleOption};
-use hyperfine::units::Second;
+use crate::hyperfine::types::{BenchmarkResult, OutputStyleOption};
+use crate::hyperfine::units::Second;
 
 use std::cmp::Ordering;
 use std::iter::Iterator;
diff --git a/src/hyperfine/shell.rs b/src/hyperfine/shell.rs
index 543bc21..7a84381 100644
--- a/src/hyperfine/shell.rs
+++ b/src/hyperfine/shell.rs
@@ -2,7 +2,7 @@ use std;
 use std::io;
 use std::process::{Command, ExitStatus, Stdio};
 
-use hyperfine::timer::get_cpu_timer;
+use crate::hyperfine::timer::get_cpu_timer;
 
 /// Used to indicate the result of running a command
 #[derive(Debug, Copy, Clone)]
diff --git a/src/hyperfine/timer/internal.rs b/src/hyperfine/timer/internal.rs
index 49ef3ce..ec3b572 100644
--- a/src/hyperfine/timer/internal.rs
+++ b/src/hyperfine/timer/internal.rs
@@ -1,4 +1,4 @@
-use hyperfine::units::Second;
+use crate::hyperfine::units::Second;
 
 #[derive(Debug, Copy, Clone)]
 pub struct CPUTimes {
diff --git a/src/hyperfine/timer/mod.rs b/src/hyperfine/timer/mod.rs
index 9fe26bf..68e0ef7 100644
--- a/src/hyperfine/timer/mod.rs
+++ b/src/hyperfine/timer/mod.rs
@@ -2,6 +2,8 @@ mod internal;
 
 pub mod wallclocktimer;
 
+use cfg_if::cfg_if;
+
 cfg_if! {
     if #[cfg(windows)] {
         mod windows_timer;
diff --git a/src/hyperfine/timer/unix_timer.rs b/src/hyperfine/timer/unix_timer.rs
index 8d940dd..f65b207 100644
--- a/src/hyperfine/timer/unix_timer.rs
+++ b/src/hyperfine/timer/unix_timer.rs
@@ -1,13 +1,13 @@
 #![cfg(not(windows))]
 
 use super::internal::{CPUInterval, CPUTimes};
-use hyperfine::timer::{TimerStart, TimerStop};
-use hyperfine::units::Second;
+use crate::hyperfine::timer::{TimerStart, TimerStop};
+use crate::hyperfine::units::Second;
 
 use std::mem;
 use std::process::Child;
 
-pub fn get_cpu_timer() -> Box<TimerStop<Result = (Second, Second)>> {
+pub fn get_cpu_timer() -> Box<dyn TimerStop<Result = (Second, Second)>> {
     Box::new(CPUTimer::start())
 }
 
@@ -66,6 +66,9 @@ fn cpu_time_interval(start: &CPUTimes, end: &CPUTimes) -> CPUInterval {
     }
 }
 
+#[cfg(test)]
+use approx::assert_relative_eq;
+
 #[test]
 fn test_cpu_time_interval() {
     let t_a = CPUTimes {
diff --git a/src/hyperfine/timer/wallclocktimer.rs b/src/hyperfine/timer/wallclocktimer.rs
index b28a24e..8b8a14b 100644
--- a/src/hyperfine/timer/wallclocktimer.rs
+++ b/src/hyperfine/timer/wallclocktimer.rs
@@ -1,8 +1,8 @@
 use std::process::Child;
 use std::time::Instant;
 
-use hyperfine::timer::{TimerStart, TimerStop};
-use hyperfine::units::Second;
+use crate::hyperfine::timer::{TimerStart, TimerStop};
+use crate::hyperfine::units::Second;
 
 pub struct WallClockTimer {
     start: Instant,
diff --git a/src/hyperfine/timer/windows_timer.rs b/src/hyperfine/timer/windows_timer.rs
index 4471e8d..2ddfc95 100644
--- a/src/hyperfine/timer/windows_timer.rs
+++ b/src/hyperfine/timer/windows_timer.rs
@@ -1,8 +1,8 @@
 #![cfg(windows)]
 
 use super::internal::CPUTimes;
-use hyperfine::timer::{TimerStart, TimerStop};
-use hyperfine::units::Second;
+use crate::hyperfine::timer::{TimerStart, TimerStop};
+use crate::hyperfine::units::Second;
 
 use winapi::um::processthreadsapi::GetProcessTimes;
 use winapi::um::winnt::HANDLE;
diff --git a/src/hyperfine/types.rs b/src/hyperfine/types.rs
index 784af51..fbd71aa 100644
--- a/src/hyperfine/types.rs
+++ b/src/hyperfine/types.rs
@@ -1,7 +1,8 @@
 /// This module contains common internal types.
+use serde::*;
 use std::fmt;
 
-use hyperfine::units::{Second, Unit};
+use crate::hyperfine::units::{Second, Unit};
 
 #[cfg(not(windows))]
 pub const DEFAULT_SHELL: &str = "sh";
@@ -50,7 +51,7 @@ impl<'a> Command<'a> {
 }
 
 impl<'a> fmt::Display for Command<'a> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.get_shell_command())
     }
 }
diff --git a/src/hyperfine/warnings.rs b/src/hyperfine/warnings.rs
index d14df60..95a3e16 100644
--- a/src/hyperfine/warnings.rs
+++ b/src/hyperfine/warnings.rs
@@ -1,8 +1,8 @@
 use std::fmt;
 
-use hyperfine::format::format_duration;
-use hyperfine::internal::MIN_EXECUTION_TIME;
-use hyperfine::units::Second;
+use crate::hyperfine::format::format_duration;
+use crate::hyperfine::internal::MIN_EXECUTION_TIME;
+use crate::hyperfine::units::Second;
 
 /// A list of all possible warnings
 pub enum Warnings {
@@ -13,7 +13,7 @@ pub enum Warnings {
 }
 
 impl fmt::Display for Warnings {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match *self {
             Warnings::FastExecutionTime => write!(
                 f,
diff --git a/src/main.rs b/src/main.rs
index 730cd4a..743289a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,33 +1,3 @@
-extern crate atty;
-
-#[macro_use]
-extern crate cfg_if;
-
-#[macro_use]
-extern crate clap;
-extern crate colored;
-extern crate csv;
-extern crate indicatif;
-extern crate serde;
-
-#[macro_use]
-extern crate serde_derive;
-extern crate serde_json;
-extern crate statistical;
-
-// Os-specific dependencies
-cfg_if! {
-    if #[cfg(windows)] {
-        extern crate winapi;
-    } else {
-        extern crate libc;
-    }
-}
-
-#[cfg(test)]
-#[macro_use]
-extern crate approx;
-
 use std::cmp;
 use std::env;
 use std::error::Error;
@@ -40,15 +10,15 @@ use colored::*;
 
 mod hyperfine;
 
-use hyperfine::app::get_arg_matches;
-use hyperfine::benchmark::{mean_shell_spawning_time, run_benchmark};
-use hyperfine::error::{OptionsError, ParameterScanError};
-use hyperfine::export::{ExportManager, ExportType};
-use hyperfine::internal::write_benchmark_comparison;
-use hyperfine::types::{
+use crate::hyperfine::app::get_arg_matches;
+use crate::hyperfine::benchmark::{mean_shell_spawning_time, run_benchmark};
+use crate::hyperfine::error::{OptionsError, ParameterScanError};
+use crate::hyperfine::export::{ExportManager, ExportType};
+use crate::hyperfine::internal::write_benchmark_comparison;
+use crate::hyperfine::types::{
     BenchmarkResult, CmdFailureAction, Command, HyperfineOptions, OutputStyleOption,
 };
-use hyperfine::units::Unit;
+use crate::hyperfine::units::Unit;
 
 /// Print error message to stderr and terminate
 pub fn error(message: &str) -> ! {
@@ -57,7 +27,7 @@ pub fn error(message: &str) -> ! {
 }
 
 /// Runs the benchmark for the given commands
-fn run(commands: &Vec<Command>, options: &HyperfineOptions) -> io::Result<Vec<BenchmarkResult>> {
+fn run(commands: &Vec<Command<'_>>, options: &HyperfineOptions) -> io::Result<Vec<BenchmarkResult>> {
     let shell_spawning_time =
         mean_shell_spawning_time(&options.shell, &options.output_style, options.show_output)?;
 
@@ -118,7 +88,7 @@ fn main() {
 }
 
 /// Build the HyperfineOptions that correspond to the given ArgMatches
-fn build_hyperfine_options(matches: &ArgMatches) -> Result<HyperfineOptions, OptionsError> {
+fn build_hyperfine_options(matches: &ArgMatches<'_>) -> Result<HyperfineOptions, OptionsError> {
     let mut options = HyperfineOptions::default();
     let str_to_u64 = |n| u64::from_str_radix(n, 10).ok();
 
@@ -214,7 +184,7 @@ fn build_hyperfine_options(matches: &ArgMatches) -> Result<HyperfineOptions, Opt
 
 /// Build the ExportManager that will export the results specified
 /// in the given ArgMatches
-fn build_export_manager(matches: &ArgMatches) -> ExportManager {
+fn build_export_manager(matches: &ArgMatches<'_>) -> ExportManager {
     let mut export_manager = ExportManager::new();
     {
         let mut add_exporter = |flag, exporttype| {
@@ -231,7 +201,7 @@ fn build_export_manager(matches: &ArgMatches) -> ExportManager {
 }
 
 /// Build the commands to benchmark
-fn build_commands<'a>(matches: &'a ArgMatches) -> Vec<Command<'a>> {
+fn build_commands<'a>(matches: &'a ArgMatches<'_>) -> Vec<Command<'a>> {
     let command_strings = matches.values_of("command").unwrap();
 
     let commands = if let Some(args) = matches.values_of("parameter-scan") {