diff --git a/src/arch/arch.rs b/src/arch/arch.rs
index 17a6e9f53..d27b5d216 100644
--- a/src/arch/arch.rs
+++ b/src/arch/arch.rs
@@ -15,9 +15,9 @@ extern crate uucore;
 
 use platform_info::*;
 
-static SYNTAX: &'static str = "";
-static SUMMARY: &'static str = "Determine architecture name for current machine.";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "";
+static SUMMARY: &str = "Determine architecture name for current machine.";
+static LONG_HELP: &str = "";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     new_coreopts!(SYNTAX, SUMMARY, LONG_HELP).parse(args);
diff --git a/src/base32/base32.rs b/src/base32/base32.rs
index c0dc5e613..e87d982c5 100644
--- a/src/base32/base32.rs
+++ b/src/base32/base32.rs
@@ -16,10 +16,10 @@ use std::fs::File;
 use std::io::{stdin, BufReader, Read};
 use std::path::Path;
 
-static SYNTAX: &'static str = "[OPTION]... [FILE]";
-static SUMMARY: &'static str =
+static SYNTAX: &str = "[OPTION]... [FILE]";
+static SUMMARY: &str =
     "Base32 encode or decode FILE, or standard input, to standard output.";
-static LONG_HELP: &'static str = "
+static LONG_HELP: &str = "
  With no FILE, or when FILE is -, read standard input.
 
  The data are encoded as described for the base32 alphabet in RFC
diff --git a/src/base64/base64.rs b/src/base64/base64.rs
index ac7e350b8..68c517e22 100644
--- a/src/base64/base64.rs
+++ b/src/base64/base64.rs
@@ -17,10 +17,10 @@ use std::fs::File;
 use std::io::{stdin, BufReader, Read};
 use std::path::Path;
 
-static SYNTAX: &'static str = "[OPTION]... [FILE]";
-static SUMMARY: &'static str =
+static SYNTAX: &str = "[OPTION]... [FILE]";
+static SUMMARY: &str =
     "Base64 encode or decode FILE, or standard input, to standard output.";
-static LONG_HELP: &'static str = "
+static LONG_HELP: &str = "
  With no FILE, or when FILE is -, read standard input.
 
  The data are encoded as described for the base64 alphabet in RFC
diff --git a/src/basename/basename.rs b/src/basename/basename.rs
index fa8e03e50..9711efea3 100644
--- a/src/basename/basename.rs
+++ b/src/basename/basename.rs
@@ -14,11 +14,11 @@ extern crate uucore;
 
 use std::path::{is_separator, PathBuf};
 
-static NAME: &'static str = "basename";
-static SYNTAX: &'static str = "NAME [SUFFIX]";
-static SUMMARY: &'static str = "Print NAME with any leading directory components removed
+static NAME: &str = "basename";
+static SYNTAX: &str = "NAME [SUFFIX]";
+static SUMMARY: &str = "Print NAME with any leading directory components removed
  If specified, also remove a trailing SUFFIX";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     //
diff --git a/src/cat/cat.rs b/src/cat/cat.rs
index 38b5753e1..5885a7c0f 100644
--- a/src/cat/cat.rs
+++ b/src/cat/cat.rs
@@ -31,10 +31,10 @@ use std::os::unix::fs::FileTypeExt;
 #[cfg(unix)]
 use unix_socket::UnixStream;
 
-static SYNTAX: &'static str = "[OPTION]... [FILE]...";
-static SUMMARY: &'static str = "Concatenate FILE(s), or standard input, to standard output
+static SYNTAX: &str = "[OPTION]... [FILE]...";
+static SUMMARY: &str = "Concatenate FILE(s), or standard input, to standard output
  With no FILE, or when FILE is -, read standard input.";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 #[derive(PartialEq)]
 enum NumberingMode {
diff --git a/src/chgrp/chgrp.rs b/src/chgrp/chgrp.rs
index a5e0aa52b..ed50432d3 100644
--- a/src/chgrp/chgrp.rs
+++ b/src/chgrp/chgrp.rs
@@ -29,9 +29,9 @@ use std::path::Path;
 use std::ffi::CString;
 use std::os::unix::ffi::OsStrExt;
 
-static SYNTAX: &'static str =
+static SYNTAX: &str =
     "chgrp [OPTION]... GROUP FILE...\n or :  chgrp [OPTION]... --reference=RFILE FILE...";
-static SUMMARY: &'static str = "Change the group of each FILE to GROUP.";
+static SUMMARY: &str = "Change the group of each FILE to GROUP.";
 
 const FTS_COMFOLLOW: u8 = 1;
 const FTS_PHYSICAL: u8 = 1 << 1;
diff --git a/src/chown/chown.rs b/src/chown/chown.rs
index 5a913ecfa..d594ffa61 100644
--- a/src/chown/chown.rs
+++ b/src/chown/chown.rs
@@ -30,9 +30,9 @@ use std::convert::AsRef;
 use std::ffi::CString;
 use std::os::unix::ffi::OsStrExt;
 
-static SYNTAX: &'static str =
+static SYNTAX: &str =
     "[OPTION]... [OWNER][:[GROUP]] FILE...\n chown [OPTION]... --reference=RFILE FILE...";
-static SUMMARY: &'static str = "change file owner and group";
+static SUMMARY: &str = "change file owner and group";
 
 const FTS_COMFOLLOW: u8 = 1;
 const FTS_PHYSICAL: u8 = 1 << 1;
diff --git a/src/chroot/chroot.rs b/src/chroot/chroot.rs
index ab0b9a7fd..a7973e8fe 100644
--- a/src/chroot/chroot.rs
+++ b/src/chroot/chroot.rs
@@ -23,10 +23,10 @@ use std::iter::FromIterator;
 use std::path::Path;
 use std::process::Command;
 
-static NAME: &'static str = "chroot";
-static SYNTAX: &'static str = "[OPTION]... NEWROOT [COMMAND [ARG]...]";
-static SUMMARY: &'static str = "Run COMMAND with root directory set to NEWROOT.";
-static LONG_HELP: &'static str = "
+static NAME: &str = "chroot";
+static SYNTAX: &str = "[OPTION]... NEWROOT [COMMAND [ARG]...]";
+static SUMMARY: &str = "Run COMMAND with root directory set to NEWROOT.";
+static LONG_HELP: &str = "
  If COMMAND is not specified, it defaults to '$(SHELL) -i'.
  If $(SHELL) is not set, /bin/sh is used.
 ";
diff --git a/src/cksum/build.rs b/src/cksum/build.rs
index 98736424d..37c48db5c 100644
--- a/src/cksum/build.rs
+++ b/src/cksum/build.rs
@@ -13,7 +13,7 @@ use std::fs::File;
 use std::io::Write;
 use std::path::Path;
 
-static CRC_TABLE_LEN: usize = 256;
+const CRC_TABLE_LEN: usize = 256;
 
 #[path = "../../mkmain.rs"]
 mod mkmain;
diff --git a/src/dirname/dirname.rs b/src/dirname/dirname.rs
index e9b773ad0..d56c9e464 100644
--- a/src/dirname/dirname.rs
+++ b/src/dirname/dirname.rs
@@ -14,10 +14,10 @@ extern crate uucore;
 
 use std::path::Path;
 
-static NAME: &'static str = "dirname";
-static SYNTAX: &'static str = "[OPTION] NAME...";
-static SUMMARY: &'static str = "strip last component from file name";
-static LONG_HELP: &'static str = "
+static NAME: &str = "dirname";
+static SYNTAX: &str = "[OPTION] NAME...";
+static SUMMARY: &str = "strip last component from file name";
+static LONG_HELP: &str = "
  Output each NAME with its last non-slash component and trailing slashes
  removed; if NAME contains no /'s, output '.' (meaning the current
  directory).
diff --git a/src/env/env.rs b/src/env/env.rs
index a456c4190..0203e3ba8 100644
--- a/src/env/env.rs
+++ b/src/env/env.rs
@@ -17,10 +17,10 @@ use std::env;
 use std::io::{stdout, Write};
 use std::process::Command;
 
-static NAME: &'static str = "env";
-static SYNTAX: &'static str = "[OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]";
-static SUMMARY: &'static str = "Set each NAME to VALUE in the environment and run COMMAND";
-static LONG_HELP: &'static str = "
+static NAME: &str = "env";
+static SYNTAX: &str = "[OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]";
+static SUMMARY: &str = "Set each NAME to VALUE in the environment and run COMMAND";
+static LONG_HELP: &str = "
  A mere - implies -i. If no COMMAND, print the resulting environment
 ";
 
diff --git a/src/expand/expand.rs b/src/expand/expand.rs
index 905677f65..6b358e90c 100644
--- a/src/expand/expand.rs
+++ b/src/expand/expand.rs
@@ -23,10 +23,10 @@ use std::iter::repeat;
 use std::str::from_utf8;
 use unicode_width::UnicodeWidthChar;
 
-static SYNTAX: &'static str = "[OPTION]... [FILE]...";
-static SUMMARY: &'static str = "Convert tabs in each FILE to spaces, writing to standard output.
+static SYNTAX: &str = "[OPTION]... [FILE]...";
+static SUMMARY: &str = "Convert tabs in each FILE to spaces, writing to standard output.
  With no FILE, or when FILE is -, read standard input.";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 static DEFAULT_TABSTOP: usize = 8;
 
diff --git a/src/factor/factor.rs b/src/factor/factor.rs
index 72224377d..e505e077d 100644
--- a/src/factor/factor.rs
+++ b/src/factor/factor.rs
@@ -29,10 +29,10 @@ mod numeric;
 
 include!(concat!(env!("OUT_DIR"), "/prime_table.rs"));
 
-static SYNTAX: &'static str = "[OPTION] [NUMBER]...";
-static SUMMARY: &'static str = "Print the prime factors of the given number(s).
+static SYNTAX: &str = "[OPTION] [NUMBER]...";
+static SUMMARY: &str = "Print the prime factors of the given number(s).
  If none are specified, read from standard input.";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 fn rho_pollard_pseudorandom_function(x: u64, a: u64, b: u64, num: u64) -> u64 {
     if num < 1 << 63 {
@@ -148,7 +148,7 @@ fn print_factors(num: u64) {
     for fac in &factors {
         print!(" {}", fac);
     }
-    println!("");
+    println!();
 }
 
 fn print_factors_str(num_str: &str) {
diff --git a/src/fmt/fmt.rs b/src/fmt/fmt.rs
index 45e1e885f..816e47ede 100644
--- a/src/fmt/fmt.rs
+++ b/src/fmt/fmt.rs
@@ -34,9 +34,9 @@ mod linebreak;
 mod parasplit;
 
 // program's NAME and VERSION are used for -V and -h
-static SYNTAX: &'static str = "[OPTION]... [FILE]...";
-static SUMMARY: &'static str = "Reformat paragraphs from input files (or stdin) to stdout.";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "[OPTION]... [FILE]...";
+static SUMMARY: &str = "Reformat paragraphs from input files (or stdin) to stdout.";
+static LONG_HELP: &str = "";
 
 pub type FileOrStdReader = BufReader<Box<Read + 'static>>;
 pub struct FmtOptions {
@@ -120,62 +120,47 @@ pub fn uumain(args: Vec<String>) -> i32 {
         fmt_opts.xanti_prefix = true;
     }
 
-    match matches.opt_str("p") {
-        Some(s) => {
-            fmt_opts.prefix = s;
-            fmt_opts.use_prefix = true;
-        }
-        None => (),
+    if let Some(s) = matches.opt_str("p") {
+        fmt_opts.prefix = s;
+        fmt_opts.use_prefix = true;
     };
 
-    match matches.opt_str("P") {
-        Some(s) => {
-            fmt_opts.anti_prefix = s;
-            fmt_opts.use_anti_prefix = true;
-        }
-        None => (),
+    if let Some(s) = matches.opt_str("P") {
+        fmt_opts.anti_prefix = s;
+        fmt_opts.use_anti_prefix = true;
     };
 
-    match matches.opt_str("w") {
-        Some(s) => {
-            fmt_opts.width = match s.parse::<usize>() {
-                Ok(t) => t,
-                Err(e) => {
-                    crash!(1, "Invalid WIDTH specification: `{}': {}", s, e);
-                }
-            };
-            fmt_opts.goal = cmp::min(fmt_opts.width * 94 / 100, fmt_opts.width - 3);
-        }
-        None => (),
-    };
-
-    match matches.opt_str("g") {
-        Some(s) => {
-            fmt_opts.goal = match s.parse::<usize>() {
-                Ok(t) => t,
-                Err(e) => {
-                    crash!(1, "Invalid GOAL specification: `{}': {}", s, e);
-                }
-            };
-            if !matches.opt_present("w") {
-                fmt_opts.width = cmp::max(fmt_opts.goal * 100 / 94, fmt_opts.goal + 3);
-            } else if fmt_opts.goal > fmt_opts.width {
-                crash!(1, "GOAL cannot be greater than WIDTH.");
+    if let Some(s) = matches.opt_str("w") {
+        fmt_opts.width = match s.parse::<usize>() {
+            Ok(t) => t,
+            Err(e) => {
+                crash!(1, "Invalid WIDTH specification: `{}': {}", s, e);
             }
-        }
-        None => (),
+        };
+        fmt_opts.goal = cmp::min(fmt_opts.width * 94 / 100, fmt_opts.width - 3);
     };
 
-    match matches.opt_str("T") {
-        Some(s) => {
-            fmt_opts.tabwidth = match s.parse::<usize>() {
-                Ok(t) => t,
-                Err(e) => {
-                    crash!(1, "Invalid TABWIDTH specification: `{}': {}", s, e);
-                }
-            };
+    if let Some(s) = matches.opt_str("g") {
+        fmt_opts.goal = match s.parse::<usize>() {
+            Ok(t) => t,
+            Err(e) => {
+                crash!(1, "Invalid GOAL specification: `{}': {}", s, e);
+            }
+        };
+        if !matches.opt_present("w") {
+            fmt_opts.width = cmp::max(fmt_opts.goal * 100 / 94, fmt_opts.goal + 3);
+        } else if fmt_opts.goal > fmt_opts.width {
+            crash!(1, "GOAL cannot be greater than WIDTH.");
         }
-        None => (),
+    };
+
+    if let Some(s) = matches.opt_str("T") {
+        fmt_opts.tabwidth = match s.parse::<usize>() {
+            Ok(t) => t,
+            Err(e) => {
+                crash!(1, "Invalid TABWIDTH specification: `{}': {}", s, e);
+            }
+        };
     };
 
     if fmt_opts.tabwidth < 1 {
@@ -208,7 +193,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
             match para_result {
                 Err(s) => {
                     silent_unwrap!(ostream.write_all(s.as_bytes()));
-                    silent_unwrap!(ostream.write_all("\n".as_bytes()));
+                    silent_unwrap!(ostream.write_all(b"\n"));
                 }
                 Ok(para) => break_lines(&para, &fmt_opts, &mut ostream),
             }
diff --git a/src/fmt/linebreak.rs b/src/fmt/linebreak.rs
index 1c47c5c64..2bf7b0ef9 100644
--- a/src/fmt/linebreak.rs
+++ b/src/fmt/linebreak.rs
@@ -53,7 +53,7 @@ pub fn break_lines(para: &Paragraph, opts: &FmtOptions, ostream: &mut BufWriter<
     let (w, w_len) = match p_words_words.next() {
         Some(winfo) => (winfo.word, winfo.word_nchars),
         None => {
-            silent_unwrap!(ostream.write_all("\n".as_bytes()));
+            silent_unwrap!(ostream.write_all(b"\n"));
             return;
         }
     };
@@ -77,12 +77,12 @@ pub fn break_lines(para: &Paragraph, opts: &FmtOptions, ostream: &mut BufWriter<
     let uniform = para.mail_header || opts.uniform;
 
     let mut break_args = BreakArgs {
-        opts: opts,
+        opts,
         init_len: p_init_len,
         indent_str: &p_indent[..],
         indent_len: p_indent_len,
-        uniform: uniform,
-        ostream: ostream,
+        uniform,
+        ostream,
     };
 
     if opts.quick || para.mail_header {
@@ -98,7 +98,7 @@ fn break_simple<'a, T: Iterator<Item = &'a WordInfo<'a>>>(iter: T, args: &mut Br
     iter.fold((args.init_len, false), |l, winfo| {
         accum_words_simple(args, l, winfo)
     });
-    silent_unwrap!(args.ostream.write_all("\n".as_bytes()));
+    silent_unwrap!(args.ostream.write_all(b"\n"));
 }
 
 fn accum_words_simple<'a>(
@@ -199,7 +199,7 @@ fn break_knuth_plass<'a, T: Clone + Iterator<Item = &'a WordInfo<'a>>>(
         fresh = false;
         write_with_spaces(word, slen, args.ostream);
     }
-    silent_unwrap!(args.ostream.write_all("\n".as_bytes()));
+    silent_unwrap!(args.ostream.write_all(b"\n"));
 }
 
 struct LineBreak<'a> {
@@ -381,7 +381,7 @@ fn build_best_path<'a>(paths: &[LineBreak<'a>], active: &[usize]) -> Vec<(&'a Wo
 }
 
 // "infinite" badness is more like (1+BAD_INFTY)^2 because of how demerits are computed
-const BAD_INFTY: i64 = 10000000;
+const BAD_INFTY: i64 = 10_000_000;
 const BAD_INFTY_SQ: i64 = BAD_INFTY * BAD_INFTY;
 // badness = BAD_MULT * abs(r) ^ 3
 const BAD_MULT: f32 = 100.0;
@@ -451,7 +451,7 @@ fn restart_active_breaks<'a>(
     LineBreak {
         prev: act_idx,
         linebreak: Some(w),
-        break_before: break_before,
+        break_before,
         demerits: 0, // this is the only active break, so we can reset the demerit count
         prev_rat: if break_before { 1.0 } else { -1.0 },
         length: line_length,
@@ -492,16 +492,16 @@ fn slice_if_fresh(
 
 // Write a newline and add the indent.
 fn write_newline(indent: &str, ostream: &mut BufWriter<Stdout>) {
-    silent_unwrap!(ostream.write_all("\n".as_bytes()));
+    silent_unwrap!(ostream.write_all(b"\n"));
     silent_unwrap!(ostream.write_all(indent.as_bytes()));
 }
 
 // Write the word, along with slen spaces.
 fn write_with_spaces(word: &str, slen: usize, ostream: &mut BufWriter<Stdout>) {
     if slen == 2 {
-        silent_unwrap!(ostream.write_all("  ".as_bytes()));
+        silent_unwrap!(ostream.write_all(b"  "));
     } else if slen == 1 {
-        silent_unwrap!(ostream.write_all(" ".as_bytes()));
+        silent_unwrap!(ostream.write_all(b" "));
     }
     silent_unwrap!(ostream.write_all(word.as_bytes()));
 }
diff --git a/src/fmt/parasplit.rs b/src/fmt/parasplit.rs
index 208b3bf04..42ceccf81 100644
--- a/src/fmt/parasplit.rs
+++ b/src/fmt/parasplit.rs
@@ -73,8 +73,8 @@ pub struct FileLines<'a> {
 impl<'a> FileLines<'a> {
     fn new<'b>(opts: &'b FmtOptions, lines: Lines<&'b mut FileOrStdReader>) -> FileLines<'b> {
         FileLines {
-            opts: opts,
-            lines: lines,
+            opts,
+            lines,
         }
     }
 
@@ -197,10 +197,10 @@ impl<'a> Iterator for FileLines<'a> {
 
         Some(Line::FormatLine(FileLine {
             line: n,
-            indent_end: indent_end,
+            indent_end,
             pfxind_end: poffset,
-            indent_len: indent_len,
-            prefix_len: prefix_len,
+            indent_len,
+            prefix_len,
         }))
     }
 }
@@ -234,9 +234,9 @@ impl<'a> ParagraphStream<'a> {
         let lines = FileLines::new(opts, reader.lines()).peekable();
         // at the beginning of the file, we might find mail headers
         ParagraphStream {
-            lines: lines,
+            lines,
             next_mail: true,
-            opts: opts,
+            opts,
         }
     }
 
@@ -405,12 +405,12 @@ impl<'a> Iterator for ParagraphStream<'a> {
 
         Some(Ok(Paragraph {
             lines: p_lines,
-            init_str: init_str,
-            init_len: init_len,
-            init_end: init_end,
-            indent_str: indent_str,
-            indent_len: indent_len,
-            indent_end: indent_end,
+            init_str,
+            init_len,
+            init_end,
+            indent_str,
+            indent_len,
+            indent_end,
             mail_header: in_mail,
         }))
     }
@@ -425,8 +425,8 @@ pub struct ParaWords<'a> {
 impl<'a> ParaWords<'a> {
     pub fn new<'b>(opts: &'b FmtOptions, para: &'b Paragraph) -> ParaWords<'b> {
         let mut pw = ParaWords {
-            opts: opts,
-            para: para,
+            opts,
+            para,
             words: Vec::new(),
         };
         pw.create_words();
@@ -522,7 +522,7 @@ impl<'a> WordSplit<'a> {
         // wordsplits *must* start at a non-whitespace character
         let trim_string = string.trim_left();
         WordSplit {
-            opts: opts,
+            opts,
             string: trim_string,
             length: string.len(),
             position: 0,
@@ -610,14 +610,14 @@ impl<'a> Iterator for WordSplit<'a> {
         };
 
         Some(WordInfo {
-            word: word,
+            word,
             word_start: word_start_relative,
-            word_nchars: word_nchars,
-            before_tab: before_tab,
-            after_tab: after_tab,
+            word_nchars,
+            before_tab,
+            after_tab,
             sentence_start: is_start_of_sentence,
             ends_punct: self.prev_punct,
-            new_line: new_line,
+            new_line,
         })
     }
 }
diff --git a/src/fold/fold.rs b/src/fold/fold.rs
index d2d33fecc..8e083df32 100644
--- a/src/fold/fold.rs
+++ b/src/fold/fold.rs
@@ -16,10 +16,10 @@ use std::fs::File;
 use std::io::{stdin, BufRead, BufReader, Read};
 use std::path::Path;
 
-static SYNTAX: &'static str = "[OPTION]... [FILE]...";
-static SUMMARY: &'static str = "Writes each file (or standard input if no files are given)
+static SYNTAX: &str = "[OPTION]... [FILE]...";
+static SUMMARY: &str = "Writes each file (or standard input if no files are given)
  to standard output whilst breaking long lines";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let (args, obs_width) = handle_obsolete(&args[..]);
@@ -70,7 +70,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
 fn handle_obsolete(args: &[String]) -> (Vec<String>, Option<String>) {
     for (i, arg) in args.iter().enumerate() {
         let slice = &arg;
-        if slice.chars().next().unwrap() == '-' && slice.len() > 1
+        if slice.starts_with('-') && slice.len() > 1
             && slice.chars().nth(1).unwrap().is_digit(10)
         {
             let mut v = args.to_vec();
@@ -123,10 +123,10 @@ fn fold_file<T: Read>(mut file: BufReader<T>, bytes: bool, spaces: bool, width:
             }
         } else {
             let mut len = line.chars().count();
-            let newline = line.ends_with("\n");
+            let newline = line.ends_with('\n');
             if newline {
                 if len == 1 {
-                    println!("");
+                    println!();
                     continue;
                 }
                 len -= 1;
diff --git a/src/groups/groups.rs b/src/groups/groups.rs
index a667b1a9c..406429eea 100644
--- a/src/groups/groups.rs
+++ b/src/groups/groups.rs
@@ -14,8 +14,8 @@
 extern crate uucore;
 use uucore::entries::{get_groups, Locate, Passwd, gid2grp};
 
-static SYNTAX: &'static str = "[user]";
-static SUMMARY: &'static str = "display current group names";
+static SYNTAX: &str = "[user]";
+static SUMMARY: &str = "display current group names";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let matches = new_coreopts!(SYNTAX, SUMMARY, "").parse(args);
@@ -30,19 +30,17 @@ pub fn uumain(args: Vec<String>) -> i32 {
                 .collect::<Vec<_>>()
                 .join(" ")
         );
+    } else if let Ok(p) = Passwd::locate(matches.free[0].as_str()) {
+        println!(
+            "{}",
+            p.belongs_to()
+                .iter()
+                .map(|&g| gid2grp(g).unwrap())
+                .collect::<Vec<_>>()
+                .join(" ")
+        );
     } else {
-        if let Ok(p) = Passwd::locate(matches.free[0].as_str()) {
-            println!(
-                "{}",
-                p.belongs_to()
-                    .iter()
-                    .map(|&g| gid2grp(g).unwrap())
-                    .collect::<Vec<_>>()
-                    .join(" ")
-            );
-        } else {
-            crash!(1, "unknown user {}", matches.free[0]);
-        }
+        crash!(1, "unknown user {}", matches.free[0]);
     }
 
     0
diff --git a/src/hashsum/hashsum.rs b/src/hashsum/hashsum.rs
index e71ed4f4e..e0f5ff428 100644
--- a/src/hashsum/hashsum.rs
+++ b/src/hashsum/hashsum.rs
@@ -38,8 +38,8 @@ use std::fs::File;
 use std::io::{self, stdin, BufRead, BufReader, Read};
 use std::path::Path;
 
-static NAME: &'static str = "hashsum";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "hashsum";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 fn is_custom_binary(program: &str) -> bool {
     match program {
@@ -493,8 +493,8 @@ fn digest_reader<'a, T: Read>(
 
     // Digest file, do not hold too much in memory at any given moment
     let windows = cfg!(windows);
-    let mut buffer = Vec::with_capacity(524288);
-    let mut vec = Vec::with_capacity(524288);
+    let mut buffer = Vec::with_capacity(524_288);
+    let mut vec = Vec::with_capacity(524_288);
     let mut looking_for_newline = false;
     loop {
         match reader.read_to_end(&mut buffer) {
@@ -504,17 +504,17 @@ fn digest_reader<'a, T: Read>(
             Ok(nread) => {
                 if windows && !binary {
                     // Windows text mode returns '\n' when reading '\r\n'
-                    for i in 0..nread {
+                    for &b in buffer.iter().take(nread) {
                         if looking_for_newline {
-                            if buffer[i] != ('\n' as u8) {
-                                vec.push('\r' as u8);
+                            if b != b'\n' {
+                                vec.push(b'\r');
                             }
-                            if buffer[i] != ('\r' as u8) {
-                                vec.push(buffer[i]);
+                            if b != b'\r' {
+                                vec.push(b);
                                 looking_for_newline = false;
                             }
-                        } else if buffer[i] != ('\r' as u8) {
-                            vec.push(buffer[i]);
+                        } else if b != b'\r' {
+                            vec.push(b);
                         } else {
                             looking_for_newline = true;
                         }
@@ -529,7 +529,7 @@ fn digest_reader<'a, T: Read>(
         }
     }
     if windows && looking_for_newline {
-        vec.push('\r' as u8);
+        vec.push(b'\r');
         digest.input(&vec);
     }
 
diff --git a/src/head/head.rs b/src/head/head.rs
index cd61e1082..efc0ab8db 100644
--- a/src/head/head.rs
+++ b/src/head/head.rs
@@ -19,9 +19,9 @@ use std::fs::File;
 use std::path::Path;
 use std::str::from_utf8;
 
-static SYNTAX: &'static str = "";
-static SUMMARY: &'static str = "";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "";
+static SUMMARY: &str = "";
+static LONG_HELP: &str = "";
 
 enum FilterMode {
     Bytes(usize),
@@ -90,16 +90,15 @@ pub fn uumain(args: Vec<String>) -> i32 {
                 }
             }
         }
-        None => match matches.opt_str("c") {
-            Some(count) => match count.parse::<usize>() {
+        None => if let Some(count) = matches.opt_str("c") {
+            match count.parse::<usize>() {
                 Ok(m) => settings.mode = FilterMode::Bytes(m),
                 Err(e) => {
                     show_error!("invalid byte count '{}': {}", count, e);
                     return 1;
                 }
-            },
-            None => {}
-        },
+            }
+        }
     };
 
     let quiet = matches.opt_present("q");
@@ -129,7 +128,7 @@ pub fn uumain(args: Vec<String>) -> i32 {
         for file in &files {
             if settings.verbose {
                 if !firstime {
-                    println!("");
+                    println!();
                 }
                 println!("==> {} <==", file);
             }
@@ -160,7 +159,7 @@ fn obsolete(options: &[String]) -> (Vec<String>, Option<usize>) {
         let current = options[a].clone();
         let current = current.as_bytes();
 
-        if current.len() > 1 && current[0] == '-' as u8 {
+        if current.len() > 1 && current[0] == b'-' {
             let len = current.len();
             for pos in 1..len {
                 // Ensure that the argument is only made out of digits
diff --git a/src/hostid/hostid.rs b/src/hostid/hostid.rs
index a7c056502..1529e99b5 100644
--- a/src/hostid/hostid.rs
+++ b/src/hostid/hostid.rs
@@ -16,9 +16,9 @@ extern crate uucore;
 
 use libc::c_long;
 
-static SYNTAX: &'static str = "[options]";
-static SUMMARY: &'static str = "";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "[options]";
+static SUMMARY: &str = "";
+static LONG_HELP: &str = "";
 
 pub enum Mode {
     HostId,
@@ -49,6 +49,6 @@ fn hostid() {
         result = gethostid();
     }
 
-    result &= 0xffffffff;
+    result &= 0xffff_ffff;
     println!("{:0>8x}", result);
 }
diff --git a/src/hostname/hostname.rs b/src/hostname/hostname.rs
index 80b60a699..7808b6c38 100644
--- a/src/hostname/hostname.rs
+++ b/src/hostname/hostname.rs
@@ -38,9 +38,9 @@ use libc::gethostname;
 #[cfg(not(windows))]
 use libc::sethostname;
 
-const SYNTAX: &'static str = "[OPTION]... [HOSTNAME]";
-const SUMMARY: &'static str = "Print or set the system's host name.";
-const LONG_HELP: &'static str = "";
+const SYNTAX: &str = "[OPTION]... [HOSTNAME]";
+const SUMMARY: &str = "Print or set the system's host name.";
+const LONG_HELP: &str = "";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     #[cfg(windows)]
diff --git a/src/install/install.rs b/src/install/install.rs
index dc7b8d223..4d7aeb611 100644
--- a/src/install/install.rs
+++ b/src/install/install.rs
@@ -21,10 +21,10 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use std::result::Result;
 
-static NAME: &'static str = "install";
-static SUMMARY: &'static str = "Copy SOURCE to DEST or multiple SOURCE(s) to the existing
+static NAME: &str = "install";
+static SUMMARY: &str = "Copy SOURCE to DEST or multiple SOURCE(s) to the existing
  DIRECTORY, while setting permission modes and owner/group";
-static LONG_HELP: &'static str = "";
+static LONG_HELP: &str = "";
 
 const DEFAULT_MODE: u32 = 755;
 
diff --git a/src/join/join.rs b/src/join/join.rs
index f86473259..2f26de014 100644
--- a/src/join/join.rs
+++ b/src/join/join.rs
@@ -19,8 +19,8 @@ use std::io::{stdin, BufRead, BufReader, Lines, Stdin};
 use std::cmp::{min, Ordering};
 use clap::{App, Arg};
 
-static NAME: &'static str = "join";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "join";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(Copy, Clone, PartialEq)]
 enum FileNum {
diff --git a/src/kill/kill.rs b/src/kill/kill.rs
index 1f9a69829..739efb8df 100644
--- a/src/kill/kill.rs
+++ b/src/kill/kill.rs
@@ -18,9 +18,9 @@ use libc::{c_int, pid_t};
 use std::io::Error;
 use uucore::signals::ALL_SIGNALS;
 
-static SYNTAX: &'static str = "[options] <pid> [...]";
-static SUMMARY: &'static str = "";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "[options] <pid> [...]";
+static SUMMARY: &str = "";
+static LONG_HELP: &str = "";
 
 static EXIT_OK: i32 = 0;
 static EXIT_ERR: i32 = 1;
diff --git a/src/link/link.rs b/src/link/link.rs
index 9a53f1106..4ff654f4b 100644
--- a/src/link/link.rs
+++ b/src/link/link.rs
@@ -16,9 +16,9 @@ use std::fs::hard_link;
 use std::path::Path;
 use std::io::Error;
 
-static SYNTAX: &'static str = "[OPTIONS] FILE1 FILE2";
-static SUMMARY: &'static str = "Create a link named FILE2 to FILE1";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "[OPTIONS] FILE1 FILE2";
+static SUMMARY: &str = "Create a link named FILE2 to FILE1";
+static LONG_HELP: &str = "";
 
 pub fn normalize_error_message(e: Error) -> String {
     match e.raw_os_error() {
diff --git a/src/ln/ln.rs b/src/ln/ln.rs
index 5d0cccb92..d182bd688 100644
--- a/src/ln/ln.rs
+++ b/src/ln/ln.rs
@@ -20,9 +20,9 @@ use std::os::unix::fs::symlink;
 use std::os::windows::fs::{symlink_dir, symlink_file};
 use std::path::{Path, PathBuf};
 
-static NAME: &'static str = "ln";
-static SUMMARY: &'static str = "";
-static LONG_HELP: &'static str = "
+static NAME: &str = "ln";
+static SUMMARY: &str = "";
+static LONG_HELP: &str = "
  In the 1st form, create a link to TARGET with the name LINK_NAME.
  In the 2nd form, create a link to TARGET in the current directory.
  In the 3rd and 4th forms, create links to each TARGET in DIRECTORY.
diff --git a/src/logname/logname.rs b/src/logname/logname.rs
index d573f2cee..f0551c021 100644
--- a/src/logname/logname.rs
+++ b/src/logname/logname.rs
@@ -34,9 +34,9 @@ fn get_userlogin() -> Option<String> {
     }
 }
 
-static SYNTAX: &'static str = "";
-static SUMMARY: &'static str = "Print user's login name";
-static LONG_HELP: &'static str = "";
+static SYNTAX: &str = "";
+static SUMMARY: &str = "Print user's login name";
+static LONG_HELP: &str = "";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     new_coreopts!(SYNTAX, SUMMARY, LONG_HELP).parse(args);
diff --git a/src/ls/ls.rs b/src/ls/ls.rs
index 7bfaf3461..80f57f448 100644
--- a/src/ls/ls.rs
+++ b/src/ls/ls.rs
@@ -44,16 +44,16 @@ use unicode_width::UnicodeWidthStr;
 #[cfg(windows)]
 use std::os::windows::fs::MetadataExt;
 
-static NAME: &'static str = "ls";
-static SUMMARY: &'static str = "";
-static LONG_HELP: &'static str = "
+static NAME: &str = "ls";
+static SUMMARY: &str = "";
+static LONG_HELP: &str = "
  By default, ls will list the files and contents of any directories on
  the command line, expect that it will ignore files and directories
  whose names start with '.'
 ";
 
 #[cfg(unix)]
-static DEFAULT_COLORS: &'static str = "rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:mi=00:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.m4a=00;36:*.mid=00;36:*.midi=00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.oga=00;36:*.opus=00;36:*.spx=00;36:*.xspf=00;36:";
+static DEFAULT_COLORS: &str = "rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:mi=00:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.m4a=00;36:*.mid=00;36:*.midi=00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.oga=00;36:*.opus=00;36:*.spx=00;36:*.xspf=00;36:";
 
 #[cfg(unix)]
 lazy_static! {
diff --git a/src/mkdir/mkdir.rs b/src/mkdir/mkdir.rs
index 231ce3b93..9e8581c67 100644
--- a/src/mkdir/mkdir.rs
+++ b/src/mkdir/mkdir.rs
@@ -18,8 +18,8 @@ extern crate uucore;
 use std::fs;
 use std::path::{Path, PathBuf};
 
-static NAME: &'static str = "mkdir";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "mkdir";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 /**
  * Handles option parsing
diff --git a/src/mkfifo/mkfifo.rs b/src/mkfifo/mkfifo.rs
index 3e25e0510..df1012787 100644
--- a/src/mkfifo/mkfifo.rs
+++ b/src/mkfifo/mkfifo.rs
@@ -19,8 +19,8 @@ use libc::mkfifo;
 use std::ffi::CString;
 use std::io::Error;
 
-static NAME: &'static str = "mkfifo";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "mkfifo";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/mknod/mknod.rs b/src/mknod/mknod.rs
index c950a7845..0efd7cc92 100644
--- a/src/mknod/mknod.rs
+++ b/src/mknod/mknod.rs
@@ -23,8 +23,8 @@ use getopts::Options;
 
 use std::ffi::CString;
 
-static NAME: &'static str = "mknod";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "mknod";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 const MODE_RW_UGO: mode_t = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
 
diff --git a/src/mktemp/mktemp.rs b/src/mktemp/mktemp.rs
index 2b47fe4c6..97e8a3a90 100644
--- a/src/mktemp/mktemp.rs
+++ b/src/mktemp/mktemp.rs
@@ -26,9 +26,9 @@ use tempfile::NamedTempFileOptions;
 
 mod tempdir;
 
-static NAME: &'static str = "mktemp";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
-static DEFAULT_TEMPLATE: &'static str = "tmp.XXXXXXXXXX";
+static NAME: &str = "mktemp";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
+static DEFAULT_TEMPLATE: &str = "tmp.XXXXXXXXXX";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/more/more.rs b/src/more/more.rs
index 07833928c..3a121fada 100644
--- a/src/more/more.rs
+++ b/src/more/more.rs
@@ -35,8 +35,8 @@ pub enum Mode {
     Version,
 }
 
-static NAME: &'static str = "more";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "more";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = Options::new();
diff --git a/src/mv/mv.rs b/src/mv/mv.rs
index dea29e94e..1b1ee68db 100644
--- a/src/mv/mv.rs
+++ b/src/mv/mv.rs
@@ -19,8 +19,8 @@ use std::env;
 use std::io::{stdin, BufRead, BufReader, Result};
 use std::path::{Path, PathBuf};
 
-static NAME: &'static str = "mv";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "mv";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub struct Behaviour {
     overwrite: OverwriteMode,
diff --git a/src/nice/nice.rs b/src/nice/nice.rs
index 1f79983b7..e76165a8e 100644
--- a/src/nice/nice.rs
+++ b/src/nice/nice.rs
@@ -19,8 +19,8 @@ use libc::{c_char, c_int, execvp};
 use std::ffi::CString;
 use std::io::Error;
 
-const NAME: &'static str = "nice";
-const VERSION: &'static str = env!("CARGO_PKG_VERSION");
+const NAME: &str = "nice";
+const VERSION: &str = env!("CARGO_PKG_VERSION");
 
 // XXX: PRIO_PROCESS is 0 on at least FreeBSD and Linux.  Don't know about Mac OS X.
 const PRIO_PROCESS: c_int = 0;
diff --git a/src/nl/nl.rs b/src/nl/nl.rs
index 2fb50179b..6359b4b93 100644
--- a/src/nl/nl.rs
+++ b/src/nl/nl.rs
@@ -26,9 +26,9 @@ use std::path::Path;
 
 mod helper;
 
-static NAME: &'static str = "nl";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
-static USAGE: &'static str = "nl [OPTION]... [FILE]...";
+static NAME: &str = "nl";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
+static USAGE: &str = "nl [OPTION]... [FILE]...";
 // A regular expression matching everything.
 
 // Settings store options used by nl to produce its output.
diff --git a/src/nohup/nohup.rs b/src/nohup/nohup.rs
index a54e17869..d9d7de6a3 100644
--- a/src/nohup/nohup.rs
+++ b/src/nohup/nohup.rs
@@ -25,8 +25,8 @@ use std::path::{Path, PathBuf};
 use std::env;
 use uucore::fs::{is_stderr_interactive, is_stdin_interactive, is_stdout_interactive};
 
-static NAME: &'static str = "nohup";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "nohup";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[cfg(target_os = "macos")]
 extern "C" {
diff --git a/src/nproc/nproc.rs b/src/nproc/nproc.rs
index d245836f7..6a35520cd 100644
--- a/src/nproc/nproc.rs
+++ b/src/nproc/nproc.rs
@@ -29,8 +29,8 @@ pub const _SC_NPROCESSORS_CONF: libc::c_int = 57;
 #[cfg(target_os = "netbsd")]
 pub const _SC_NPROCESSORS_CONF: libc::c_int = 1001;
 
-static NAME: &'static str = "nproc";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "nproc";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/numfmt/numfmt.rs b/src/numfmt/numfmt.rs
index 600cf462d..9b06bef7f 100644
--- a/src/numfmt/numfmt.rs
+++ b/src/numfmt/numfmt.rs
@@ -15,8 +15,8 @@ use getopts::{Matches, Options};
 use std::io::BufRead;
 use std::fmt;
 
-static NAME: &'static str = "numfmt";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "numfmt";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 type Result<T> = std::result::Result<T, String>;
 
diff --git a/src/od/od.rs b/src/od/od.rs
index 2c937e63f..03fd0d55a 100644
--- a/src/od/od.rs
+++ b/src/od/od.rs
@@ -47,10 +47,10 @@ use inputoffset::{InputOffset, Radix};
 use inputdecoder::{InputDecoder, MemoryDecoder};
 use output_info::OutputInfo;
 
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 const PEEK_BUFFER_SIZE: usize = 4; // utf-8 can be 4 bytes
 
-static USAGE: &'static str = r#"Usage:
+static USAGE: &str = r#"Usage:
     od [OPTION]... [--] [FILENAME]...
     od [-abcdDefFhHiIlLoOsxX] [FILENAME] [[+][0x]OFFSET[.][b]]
     od --traditional [OPTION]... [FILENAME] [[+][0x]OFFSET[.][b] [[+][0x]LABEL[.][b]]]
diff --git a/src/od/prn_char.rs b/src/od/prn_char.rs
index 1b01956ee..4caf068fa 100644
--- a/src/od/prn_char.rs
+++ b/src/od/prn_char.rs
@@ -13,7 +13,7 @@ pub static FORMAT_ITEM_C: FormatterItemInfo = FormatterItemInfo {
     formatter: FormatWriter::MultibyteWriter(format_item_c),
 };
 
-static A_CHRS: [&'static str; 128] = [
+static A_CHRS: [&str; 128] = [
     "nul", "soh", "stx", "etx", "eot", "enq", "ack", "bel", "bs", "ht", "nl", "vt", "ff", "cr",
     "so", "si", "dle", "dc1", "dc2", "dc3", "dc4", "nak", "syn", "etb", "can", "em", "sub", "esc",
     "fs", "gs", "rs", "us", "sp", "!", "\"", "#", "$", "%", "&", "'", "(", ")", "*", "+", ",", "-",
diff --git a/src/paste/paste.rs b/src/paste/paste.rs
index 73c9aa74f..0b5c13635 100644
--- a/src/paste/paste.rs
+++ b/src/paste/paste.rs
@@ -19,8 +19,8 @@ use std::iter::repeat;
 use std::fs::File;
 use std::path::Path;
 
-static NAME: &'static str = "paste";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "paste";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/pathchk/pathchk.rs b/src/pathchk/pathchk.rs
index dcc21b896..8159c24c9 100644
--- a/src/pathchk/pathchk.rs
+++ b/src/pathchk/pathchk.rs
@@ -30,12 +30,12 @@ enum Mode {
     Version, // show version information
 }
 
-static NAME: &'static str = "pathchk";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "pathchk";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 // a few global constants as used in the GNU implementation
-static POSIX_PATH_MAX: usize = 256;
-static POSIX_NAME_MAX: usize = 14;
+const POSIX_PATH_MAX: usize = 256;
+const POSIX_NAME_MAX: usize = 14;
 
 pub fn uumain(args: Vec<String>) -> i32 {
     // add options
diff --git a/src/pinky/pinky.rs b/src/pinky/pinky.rs
index e36d05f63..697dd158a 100644
--- a/src/pinky/pinky.rs
+++ b/src/pinky/pinky.rs
@@ -24,8 +24,8 @@ use std::os::unix::fs::MetadataExt;
 
 use std::path::PathBuf;
 
-static SYNTAX: &'static str = "[OPTION]... [USER]...";
-static SUMMARY: &'static str = "A lightweight 'finger' program;  print user information.";
+static SYNTAX: &str = "[OPTION]... [USER]...";
+static SUMMARY: &str = "A lightweight 'finger' program;  print user information.";
 
 const BUFSIZE: usize = 1024;
 
diff --git a/src/printenv/printenv.rs b/src/printenv/printenv.rs
index 72e0c2056..56ca0a653 100644
--- a/src/printenv/printenv.rs
+++ b/src/printenv/printenv.rs
@@ -18,8 +18,8 @@ extern crate uucore;
 
 use std::env;
 
-static NAME: &'static str = "printenv";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "printenv";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/printf/cli.rs b/src/printf/cli.rs
index a7a47c1d9..e69cdf3c9 100644
--- a/src/printf/cli.rs
+++ b/src/printf/cli.rs
@@ -4,8 +4,8 @@
 use std::io::{stderr, stdout, Write};
 use std::env;
 
-pub static EXIT_OK: i32 = 0;
-pub static EXIT_ERR: i32 = 1;
+pub const EXIT_OK: i32 = 0;
+pub const EXIT_ERR: i32 = 1;
 
 pub fn err_msg(msg: &str) {
     let exe_path = match env::current_exe() {
diff --git a/src/printf/printf.rs b/src/printf/printf.rs
index 086bc6a88..1842f8831 100644
--- a/src/printf/printf.rs
+++ b/src/printf/printf.rs
@@ -8,10 +8,10 @@ mod cli;
 mod memo;
 mod tokenize;
 
-static NAME: &'static str = "printf";
-static VERSION: &'static str = "0.0.1";
-static SHORT_USAGE: &'static str = "printf: usage: printf [-v var] format [arguments]";
-static LONGHELP_LEAD: &'static str = "printf
+static NAME: &str = "printf";
+static VERSION: &str = "0.0.1";
+static SHORT_USAGE: &str = "printf: usage: printf [-v var] format [arguments]";
+static LONGHELP_LEAD: &str = "printf
 
  USAGE: printf FORMATSTRING [ARGUMENT]...
 
@@ -26,7 +26,7 @@ Options:
     --version           output version information and exit
 
 ";
-static LONGHELP_BODY: &'static str = "
+static LONGHELP_BODY: &str = "
   Prints the , replacing escaped character sequences with character literals
     and substitution field sequences with passed arguments
 
diff --git a/src/ptx/ptx.rs b/src/ptx/ptx.rs
index b918b30f7..7ae696bc9 100644
--- a/src/ptx/ptx.rs
+++ b/src/ptx/ptx.rs
@@ -26,8 +26,8 @@ use std::default::Default;
 use std::fs::File;
 use std::io::{stdin, stdout, BufRead, BufReader, BufWriter, Read, Write};
 
-static NAME: &'static str = "ptx";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "ptx";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(Debug)]
 enum OutFormat {
diff --git a/src/pwd/pwd.rs b/src/pwd/pwd.rs
index 191dff488..e4658989d 100644
--- a/src/pwd/pwd.rs
+++ b/src/pwd/pwd.rs
@@ -18,8 +18,8 @@ use std::env;
 use std::path::{Path, PathBuf};
 use std::io;
 
-static NAME: &'static str = "pwd";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "pwd";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn absolute_path(path: &Path) -> io::Result<PathBuf> {
     let path_buf = path.canonicalize()?;
diff --git a/src/readlink/readlink.rs b/src/readlink/readlink.rs
index f3fab0ead..b4971e27f 100644
--- a/src/readlink/readlink.rs
+++ b/src/readlink/readlink.rs
@@ -19,8 +19,8 @@ use std::io::{stdout, Write};
 use std::path::PathBuf;
 use uucore::fs::{canonicalize, CanonicalizeMode};
 
-const NAME: &'static str = "readlink";
-const VERSION: &'static str = env!("CARGO_PKG_VERSION");
+const NAME: &str = "readlink";
+const VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/realpath/realpath.rs b/src/realpath/realpath.rs
index 258d7caf2..80e6052da 100644
--- a/src/realpath/realpath.rs
+++ b/src/realpath/realpath.rs
@@ -18,8 +18,8 @@ use std::fs;
 use std::path::{Path, PathBuf};
 use uucore::fs::{canonicalize, CanonicalizeMode};
 
-static NAME: &'static str = "realpath";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "realpath";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/relpath/relpath.rs b/src/relpath/relpath.rs
index 0138f1c0d..8e0bb4012 100644
--- a/src/relpath/relpath.rs
+++ b/src/relpath/relpath.rs
@@ -18,8 +18,8 @@ use std::env;
 use std::path::{Path, PathBuf};
 use uucore::fs::{canonicalize, CanonicalizeMode};
 
-static NAME: &'static str = "relpath";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "relpath";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/rm/rm.rs b/src/rm/rm.rs
index 3664b75f9..27fb6cc3a 100644
--- a/src/rm/rm.rs
+++ b/src/rm/rm.rs
@@ -42,8 +42,8 @@ struct Options {
     verbose: bool,
 }
 
-static NAME: &'static str = "rm";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "rm";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     // TODO: make getopts support -R in addition to -r
diff --git a/src/rmdir/rmdir.rs b/src/rmdir/rmdir.rs
index 21e514e1b..2ef50e5bd 100644
--- a/src/rmdir/rmdir.rs
+++ b/src/rmdir/rmdir.rs
@@ -17,8 +17,8 @@ extern crate uucore;
 use std::fs;
 use std::path::Path;
 
-static NAME: &'static str = "rmdir";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "rmdir";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/seq/seq.rs b/src/seq/seq.rs
index 48dec3796..4bdbbf370 100644
--- a/src/seq/seq.rs
+++ b/src/seq/seq.rs
@@ -11,8 +11,8 @@ extern crate uucore;
 use std::cmp;
 use std::io::{stdout, Write};
 
-static NAME: &'static str = "seq";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "seq";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(Clone)]
 struct SeqOptions {
diff --git a/src/shred/shred.rs b/src/shred/shred.rs
index 548d6ac87..ec4f99ff9 100644
--- a/src/shred/shred.rs
+++ b/src/shred/shred.rs
@@ -25,10 +25,10 @@ use std::path::{Path, PathBuf};
 #[macro_use]
 extern crate uucore;
 
-static NAME: &'static str = "shred";
-static VERSION_STR: &'static str = "1.0.0";
+static NAME: &str = "shred";
+static VERSION_STR: &str = "1.0.0";
 const BLOCK_SIZE: usize = 512;
-const NAMESET: &'static str = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_.";
+const NAMESET: &str = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_.";
 
 // Patterns as shown in the GNU coreutils shred implementation
 const PATTERNS: [&'static [u8]; 22] = [
diff --git a/src/shuf/shuf.rs b/src/shuf/shuf.rs
index 1ac2745ee..0d057f892 100644
--- a/src/shuf/shuf.rs
+++ b/src/shuf/shuf.rs
@@ -26,8 +26,8 @@ enum Mode {
     InputRange((usize, usize)),
 }
 
-static NAME: &'static str = "shuf";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "shuf";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/sleep/sleep.rs b/src/sleep/sleep.rs
index cda34e6b5..f27c42be5 100644
--- a/src/sleep/sleep.rs
+++ b/src/sleep/sleep.rs
@@ -17,8 +17,8 @@ extern crate uucore;
 use std::thread;
 use std::time::Duration;
 
-static NAME: &'static str = "sleep";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "sleep";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/sort/sort.rs b/src/sort/sort.rs
index 9c25af938..7185f1ba1 100644
--- a/src/sort/sort.rs
+++ b/src/sort/sort.rs
@@ -26,11 +26,11 @@ use uucore::fs::is_stdin_interactive;
 use semver::Version;
 use itertools::Itertools; // for Iterator::dedup()
 
-static NAME: &'static str = "sort";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "sort";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
-static DECIMAL_PT: char = '.';
-static THOUSANDS_SEP: char = ',';
+const DECIMAL_PT: char = '.';
+const THOUSANDS_SEP: char = ',';
 
 enum SortMode {
     Numeric,
diff --git a/src/split/split.rs b/src/split/split.rs
index 5025de6e9..e32467bb2 100644
--- a/src/split/split.rs
+++ b/src/split/split.rs
@@ -19,8 +19,8 @@ use std::fs::{File, OpenOptions};
 use std::io::{stdin, stdout, BufRead, BufReader, BufWriter, Read, Write};
 use std::path::Path;
 
-static NAME: &'static str = "split";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "split";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/stdbuf/build.rs b/src/stdbuf/build.rs
index c13d8bffc..cea536e4b 100644
--- a/src/stdbuf/build.rs
+++ b/src/stdbuf/build.rs
@@ -7,12 +7,12 @@ mod mkmain;
 
 #[cfg(target_os = "linux")]
 mod platform {
-    pub const DYLIB_EXT: &'static str = ".so";
+    pub const DYLIB_EXT: &str = ".so";
 }
 
 #[cfg(target_os = "macos")]
 mod platform {
-    pub const DYLIB_EXT: &'static str = ".dylib";
+    pub const DYLIB_EXT: &str = ".dylib";
 }
 
 fn main() {
diff --git a/src/stdbuf/stdbuf.rs b/src/stdbuf/stdbuf.rs
index 77629522b..480f96908 100644
--- a/src/stdbuf/stdbuf.rs
+++ b/src/stdbuf/stdbuf.rs
@@ -23,10 +23,10 @@ use std::os::unix::process::ExitStatusExt;
 use std::path::PathBuf;
 use std::process::Command;
 
-static NAME: &'static str = "stdbuf";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "stdbuf";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
-const STDBUF_INJECT: &'static [u8] = include_bytes!(concat!(env!("OUT_DIR"), "/libstdbuf.so"));
+const STDBUF_INJECT: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/libstdbuf.so"));
 
 enum BufferType {
     Default,
diff --git a/src/sum/sum.rs b/src/sum/sum.rs
index 445bf48d6..3e1fa5921 100644
--- a/src/sum/sum.rs
+++ b/src/sum/sum.rs
@@ -18,8 +18,8 @@ use std::fs::File;
 use std::io::{stdin, Read, Result};
 use std::path::Path;
 
-static NAME: &'static str = "sum";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "sum";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 fn bsd_sum(mut reader: Box<Read>) -> (usize, u16) {
     let mut buf = [0; 1024];
diff --git a/src/sync/sync.rs b/src/sync/sync.rs
index e1bbb2401..c9608e519 100644
--- a/src/sync/sync.rs
+++ b/src/sync/sync.rs
@@ -21,8 +21,8 @@ extern crate uucore;
 #[cfg(not(windows))]
 extern crate uucore;
 
-static NAME: &'static str = "sync";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "sync";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[cfg(unix)]
 mod platform {
diff --git a/src/tac/tac.rs b/src/tac/tac.rs
index 6da33a82c..bc14d926b 100644
--- a/src/tac/tac.rs
+++ b/src/tac/tac.rs
@@ -17,8 +17,8 @@ extern crate uucore;
 use std::fs::File;
 use std::io::{stdin, stdout, BufReader, Read, Stdout, Write};
 
-static NAME: &'static str = "tac";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tac";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/tail/tail.rs b/src/tail/tail.rs
index e26d94133..c6bbbfdf2 100755
--- a/src/tail/tail.rs
+++ b/src/tail/tail.rs
@@ -29,8 +29,8 @@ use std::str::from_utf8;
 use std::thread::sleep;
 use std::time::Duration;
 
-static NAME: &'static str = "tail";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tail";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 enum FilterMode {
     Bytes(u64),
diff --git a/src/tee/tee.rs b/src/tee/tee.rs
index 3198334c1..4285df568 100644
--- a/src/tee/tee.rs
+++ b/src/tee/tee.rs
@@ -17,8 +17,8 @@ use std::fs::OpenOptions;
 use std::io::{copy, sink, stdin, stdout, Error, ErrorKind, Read, Result, Write};
 use std::path::{Path, PathBuf};
 
-static NAME: &'static str = "tee";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tee";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     match options(&args).and_then(exec) {
diff --git a/src/test/test.rs b/src/test/test.rs
index 690fbcceb..907b44888 100644
--- a/src/test/test.rs
+++ b/src/test/test.rs
@@ -18,7 +18,7 @@ use std::ffi::OsString;
 use std::env::args_os;
 use std::str::from_utf8;
 
-static NAME: &'static str = "test";
+static NAME: &str = "test";
 
 // TODO: decide how to handle non-UTF8 input for all the utils
 // Definitely don't use [u8], try keeping it as OsStr or OsString instead
diff --git a/src/timeout/timeout.rs b/src/timeout/timeout.rs
index 1058c0f39..cd8965955 100644
--- a/src/timeout/timeout.rs
+++ b/src/timeout/timeout.rs
@@ -21,10 +21,10 @@ use std::process::{Command, Stdio};
 use std::time::Duration;
 use uucore::process::ChildExt;
 
-static NAME: &'static str = "timeout";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "timeout";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
-static ERR_EXIT_STATUS: i32 = 125;
+const ERR_EXIT_STATUS: i32 = 125;
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let program = args[0].clone();
diff --git a/src/touch/touch.rs b/src/touch/touch.rs
index 5db4deb11..194a9b0be 100644
--- a/src/touch/touch.rs
+++ b/src/touch/touch.rs
@@ -21,8 +21,8 @@ use std::fs::{self, File};
 use std::io::{self, Error};
 use std::path::Path;
 
-static NAME: &'static str = "touch";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "touch";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 // Since touch's date/timestamp parsing doesn't account for timezone, the
 // returned value from time::strptime() is UTC. We get system's timezone to
diff --git a/src/tr/tr.rs b/src/tr/tr.rs
index 86f181ee2..1fe08d454 100644
--- a/src/tr/tr.rs
+++ b/src/tr/tr.rs
@@ -28,8 +28,8 @@ use expand::ExpandSet;
 
 mod expand;
 
-static NAME: &'static str = "tr";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tr";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 const BUFFER_LEN: usize = 1024;
 
 trait SymbolTranslator {
diff --git a/src/truncate/truncate.rs b/src/truncate/truncate.rs
index ef1168daf..47da3149e 100644
--- a/src/truncate/truncate.rs
+++ b/src/truncate/truncate.rs
@@ -31,8 +31,8 @@ enum TruncateMode {
     RoundUp,
 }
 
-static NAME: &'static str = "truncate";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "truncate";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/tsort/tsort.rs b/src/tsort/tsort.rs
index a81104c5d..08c52cabe 100644
--- a/src/tsort/tsort.rs
+++ b/src/tsort/tsort.rs
@@ -20,8 +20,8 @@ use std::fs::File;
 use std::io::{stdin, BufRead, BufReader, Read};
 use std::path::Path;
 
-static NAME: &'static str = "tsort";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tsort";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/tty/tty.rs b/src/tty/tty.rs
index 173d0f0ff..eaff78c96 100644
--- a/src/tty/tty.rs
+++ b/src/tty/tty.rs
@@ -24,8 +24,8 @@ extern "C" {
     fn ttyname(filedesc: libc::c_int) -> *const libc::c_char;
 }
 
-static NAME: &'static str = "tty";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "tty";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = getopts::Options::new();
diff --git a/src/uname/uname.rs b/src/uname/uname.rs
index 307473454..05fce6366 100644
--- a/src/uname/uname.rs
+++ b/src/uname/uname.rs
@@ -19,35 +19,35 @@ extern crate uucore;
 use clap::{App, Arg};
 use platform_info::*;
 
-const VERSION: &'static str = env!("CARGO_PKG_VERSION");
-const ABOUT: &'static str = "Print certain system information.  With no OPTION, same as -s.";
+const VERSION: &str = env!("CARGO_PKG_VERSION");
+const ABOUT: &str = "Print certain system information.  With no OPTION, same as -s.";
 
-const OPT_ALL: &'static str = "all";
-const OPT_KERNELNAME: &'static str = "kernel-name";
-const OPT_NODENAME: &'static str = "nodename";
-const OPT_KERNELVERSION: &'static str = "kernel-version";
-const OPT_KERNELRELEASE: &'static str = "kernel-release";
-const OPT_MACHINE: &'static str = "machine";
+const OPT_ALL: &str = "all";
+const OPT_KERNELNAME: &str = "kernel-name";
+const OPT_NODENAME: &str = "nodename";
+const OPT_KERNELVERSION: &str = "kernel-version";
+const OPT_KERNELRELEASE: &str = "kernel-release";
+const OPT_MACHINE: &str = "machine";
 
 //FIXME: unimplemented options
 //const OPT_PROCESSOR: &'static str = "processor";
 //const OPT_HWPLATFORM: &'static str = "hardware-platform";
-const OPT_OS: &'static str = "operating-system";
+const OPT_OS: &str = "operating-system";
 
 #[cfg(target_os = "linux")]
-const HOST_OS: &'static str = "GNU/Linux";
+const HOST_OS: &str = "GNU/Linux";
 #[cfg(target_os = "windows")]
-const HOST_OS: &'static str = "Windows NT";
+const HOST_OS: &str = "Windows NT";
 #[cfg(target_os = "freebsd")]
-const HOST_OS: &'static str = "FreeBSD";
+const HOST_OS: &str = "FreeBSD";
 #[cfg(target_os = "openbsd")]
-const HOST_OS: &'static str = "OpenBSD";
+const HOST_OS: &str = "OpenBSD";
 #[cfg(target_os = "macos")]
-const HOST_OS: &'static str = "Darwin";
+const HOST_OS: &str = "Darwin";
 #[cfg(target_os = "fuchsia")]
-const HOST_OS: &'static str = "Fuchsia";
+const HOST_OS: &str = "Fuchsia";
 #[cfg(target_os = "redox")]
-const HOST_OS: &'static str = "Redox";
+const HOST_OS: &str = "Redox";
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let usage = format!("{} [OPTION]...", executable!());
diff --git a/src/unexpand/unexpand.rs b/src/unexpand/unexpand.rs
index e06caedc7..30b7343ec 100644
--- a/src/unexpand/unexpand.rs
+++ b/src/unexpand/unexpand.rs
@@ -22,10 +22,10 @@ use std::io::{stdin, stdout, BufRead, BufReader, BufWriter, Read, Stdout, Write}
 use std::str::from_utf8;
 use unicode_width::UnicodeWidthChar;
 
-static NAME: &'static str = "unexpand";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "unexpand";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
-static DEFAULT_TABSTOP: usize = 8;
+const DEFAULT_TABSTOP: usize = 8;
 
 fn tabstops_parse(s: String) -> Vec<usize> {
     let words = s.split(',').collect::<Vec<&str>>();
diff --git a/src/uniq/uniq.rs b/src/uniq/uniq.rs
index fb6918449..f82704b8b 100644
--- a/src/uniq/uniq.rs
+++ b/src/uniq/uniq.rs
@@ -21,8 +21,8 @@ use std::io::{stdin, stdout, BufRead, BufReader, BufWriter, Read, Write};
 use std::path::Path;
 use std::str::FromStr;
 
-static NAME: &'static str = "uniq";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "uniq";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[derive(PartialEq)]
 enum Delimiters {
diff --git a/src/unlink/unlink.rs b/src/unlink/unlink.rs
index adbc9e60d..9bca5e585 100644
--- a/src/unlink/unlink.rs
+++ b/src/unlink/unlink.rs
@@ -24,8 +24,8 @@ use std::io::{Error, ErrorKind};
 use std::mem::uninitialized;
 use std::ffi::CString;
 
-static NAME: &'static str = "unlink";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "unlink";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = Options::new();
diff --git a/src/uptime/uptime.rs b/src/uptime/uptime.rs
index 4c5269001..8d9d48ab4 100644
--- a/src/uptime/uptime.rs
+++ b/src/uptime/uptime.rs
@@ -23,8 +23,8 @@ pub use uucore::libc;
 
 use getopts::Options;
 
-static NAME: &'static str = "uptime";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "uptime";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 #[cfg(unix)]
 use libc::getloadavg;
diff --git a/src/users/users.rs b/src/users/users.rs
index e6c6323ad..10fb5eca5 100644
--- a/src/users/users.rs
+++ b/src/users/users.rs
@@ -21,8 +21,8 @@ use uucore::utmpx::*;
 
 use getopts::Options;
 
-static NAME: &'static str = "users";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "users";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = Options::new();
diff --git a/src/uucore/utmpx.rs b/src/uucore/utmpx.rs
index db0605a4e..2cb460fc3 100644
--- a/src/uucore/utmpx.rs
+++ b/src/uucore/utmpx.rs
@@ -64,7 +64,7 @@ macro_rules! chars2string {
 
 #[cfg(target_os = "linux")]
 mod ut {
-    pub static DEFAULT_FILE: &'static str = "/var/run/utmp";
+    pub static DEFAULT_FILE: &str = "/var/run/utmp";
 
     pub use libc::__UT_LINESIZE as UT_LINESIZE;
     pub use libc::__UT_NAMESIZE as UT_NAMESIZE;
@@ -85,7 +85,7 @@ mod ut {
 
 #[cfg(target_os = "macos")]
 mod ut {
-    pub static DEFAULT_FILE: &'static str = "/var/run/utmpx";
+    pub static DEFAULT_FILE: &str = "/var/run/utmpx";
 
     pub use libc::_UTX_LINESIZE as UT_LINESIZE;
     pub use libc::_UTX_USERSIZE as UT_NAMESIZE;
@@ -110,7 +110,7 @@ mod ut {
 mod ut {
     use super::libc;
 
-    pub static DEFAULT_FILE: &'static str = "";
+    pub static DEFAULT_FILE: &str = "";
 
     pub const UT_LINESIZE: usize = 16;
     pub const UT_NAMESIZE: usize = 32;
diff --git a/src/uutils/uutils.rs b/src/uutils/uutils.rs
index 59a2d7a40..e1480893a 100644
--- a/src/uutils/uutils.rs
+++ b/src/uutils/uutils.rs
@@ -18,8 +18,8 @@ use std::io::Write;
 
 extern crate uucore;
 
-static NAME: &'static str = "uutils";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "uutils";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 include!(concat!(env!("OUT_DIR"), "/uutils_map.rs"));
 
diff --git a/src/wc/wc.rs b/src/wc/wc.rs
index c7a3857f5..7bc6d5d7f 100644
--- a/src/wc/wc.rs
+++ b/src/wc/wc.rs
@@ -67,8 +67,8 @@ struct Result {
     max_line_length: usize,
 }
 
-static NAME: &'static str = "wc";
-static VERSION: &'static str = env!("CARGO_PKG_VERSION");
+static NAME: &str = "wc";
+static VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let mut opts = Options::new();
diff --git a/src/who/who.rs b/src/who/who.rs
index ea32749f9..83780edbd 100644
--- a/src/who/who.rs
+++ b/src/who/who.rs
@@ -19,9 +19,9 @@ use std::ffi::CStr;
 use std::path::PathBuf;
 use std::os::unix::fs::MetadataExt;
 
-static SYNTAX: &'static str = "[OPTION]... [ FILE | ARG1 ARG2 ]";
-static SUMMARY: &'static str = "Print information about users who are currently logged in.";
-static LONG_HELP: &'static str = "
+static SYNTAX: &str = "[OPTION]... [ FILE | ARG1 ARG2 ]";
+static SUMMARY: &str = "Print information about users who are currently logged in.";
+static LONG_HELP: &str = "
   -a, --all         same as -b -d --login -p -r -t -T -u
   -b, --boot        time of last system boot
   -d, --dead        print dead processes
diff --git a/src/whoami/whoami.rs b/src/whoami/whoami.rs
index 097812706..886126cbf 100644
--- a/src/whoami/whoami.rs
+++ b/src/whoami/whoami.rs
@@ -19,7 +19,7 @@ extern crate uucore;
 mod platform;
 
 // force a re-build whenever Cargo.toml changes
-const _CARGO_TOML: &'static str = include_str!("Cargo.toml");
+const _CARGO_TOML: &str = include_str!("Cargo.toml");
 
 pub fn uumain(args: Vec<String>) -> i32 {
     let app = app_from_crate!();