diff --git a/GRAMMAR.md b/GRAMMAR.md
index 03efab3ba2..1e212958f7 100644
--- a/GRAMMAR.md
+++ b/GRAMMAR.md
@@ -49,23 +49,23 @@ item          : recipe
 eol           : NEWLINE
               | COMMENT NEWLINE
 
-assignment    : NAME '=' expression eol
+alias         : 'alias' NAME ':=' NAME
 
-alias         : 'alias' NAME '=' NAME
+assignment    : NAME ':=' expression eol
 
 export        : 'export' assignment
 
 expression    : value '+' expression
               | value
 
-value         : NAME '(' arguments? ')'
+value         : NAME '(' sequence? ')'
               | STRING
               | RAW_STRING
               | BACKTICK
               | NAME
               | '(' expression ')'
 
-arguments     : expression ',' arguments
+sequence      : expression ',' sequence
               | expression ','?
 
 recipe        : '@'? NAME parameter* ('+' parameter)? ':' dependencies? body?
diff --git a/README.adoc b/README.adoc
index 372d63b249..9ba698b9a7 100644
--- a/README.adoc
+++ b/README.adoc
@@ -210,7 +210,7 @@ build test deploy lint
 Aliases allow recipes to be invoked with alternative names:
 
 ```make
-alias b = build
+alias b := build
 
 build:
   echo 'Building!'
@@ -249,9 +249,9 @@ Available recipes:
 Variables, strings, concatenation, and substitution using `{{...}}` are supported:
 
 ```make
-version = "0.2.7"
-tardir  = "awesomesauce-" + version
-tarball = tardir + ".tar.gz"
+version := "0.2.7"
+tardir  := "awesomesauce-" + version
+tarball := tardir + ".tar.gz"
 
 publish:
     rm -f {{tarball}}
@@ -285,29 +285,29 @@ braces:
 Double-quoted strings support escape sequences:
 
 ```make
-string-with-tab             = "\t"
-string-with-newline         = "\n"
-string-with-carriage-return = "\r"
-string-with-double-quote    = "\""
-string-with-slash           = "\\"
+string-with-tab             := "\t"
+string-with-newline         := "\n"
+string-with-carriage-return := "\r"
+string-with-double-quote    := "\""
+string-with-slash           := "\\"
 ```
 
 ```sh
 $ just --evaluate
-"tring-with-carriage-return = "
-string-with-double-quote    = """
-string-with-newline         = "
+"tring-with-carriage-return := "
+string-with-double-quote    := """
+string-with-newline         := "
 "
-string-with-slash           = "\"
-string-with-tab             = "     "
+string-with-slash           := "\"
+string-with-tab             := "     "
 ```
 
 Single-quoted strings do not recognize escape sequences and may contain line breaks:
 
 ```make
-escapes = '\t\n\r\"\\'
+escapes := '\t\n\r\"\\'
 
-line-breaks = 'hello
+line-breaks := 'hello
 this
 is
   a
@@ -318,9 +318,9 @@ string!
 
 ```sh
 $ just --evaluate
-escapes = "\t\n\r\"\\"
+escapes := "\t\n\r\"\\"
 
-line-breaks = "hello
+line-breaks := "hello
 this
 is
   a
@@ -410,7 +410,7 @@ Starting server with database localhost:6379 on port 1337...
 Backticks can be used to store the result of commands:
 
 ```make
-localhost = `dumpinterfaces | cut -d: -f2 | sed 's/\/.*//' | sed 's/ //g'`
+localhost := `dumpinterfaces | cut -d: -f2 | sed 's/\/.*//' | sed 's/ //g'`
 
 serve:
     ./serve {{localhost}} 8080
@@ -421,7 +421,7 @@ serve:
 Variables can be overridden from the command line.
 
 ```make
-os = "linux"
+os := "linux"
 
 test: build
     ./test --test {{os}}
@@ -457,7 +457,7 @@ $ just --set os bsd
 Assignments prefixed with the `export` keyword will be exported to recipes as environment variables:
 
 ```make
-export RUST_BACKTRACE = "1"
+export RUST_BACKTRACE := "1"
 
 test:
     # will print a stack trace if it crashes
@@ -487,7 +487,7 @@ cd my-awesome-project && make
 Parameters may have default values:
 
 ```make
-default = 'all'
+default := 'all'
 
 test target tests=default:
     @echo 'Testing {{target}}:{{tests}}...'
@@ -513,7 +513,7 @@ Testing server:unit...
 Default values may be arbitrary expressions, but concatenations must be parenthesized:
 
 ```make
-arch = "wasm"
+arch := "wasm"
 
 test triple=(arch + "-unknown-unknown"):
   ./test {{triple}}
diff --git a/justfile b/justfile
index 27300064b8..82c9c2a9c2 100755
--- a/justfile
+++ b/justfile
@@ -2,9 +2,9 @@
 # ^ A shebang isn't required, but allows a justfile to be executed
 #   like a script, with `./justfile test`, for example.
 
-bt='0'
+bt = '0'
 
-export RUST_BACKTRACE=bt
+export RUST_BACKTRACE = bt
 
 alias t = test
 
diff --git a/src/alias.rs b/src/alias.rs
index ad4e8262a0..b1ae10e371 100644
--- a/src/alias.rs
+++ b/src/alias.rs
@@ -10,6 +10,6 @@ pub struct Alias<'a> {
 
 impl<'a> Display for Alias<'a> {
   fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-    write!(f, "alias {} = {}", self.name, self.target)
+    write!(f, "alias {} := {}", self.name, self.target)
   }
 }
diff --git a/src/color.rs b/src/color.rs
index c9bb990f32..196c483a41 100644
--- a/src/color.rs
+++ b/src/color.rs
@@ -76,6 +76,10 @@ impl Color {
     self.restyle(Style::new().fg(Red).bold())
   }
 
+  pub fn warning(self) -> Color {
+    self.restyle(Style::new().fg(Yellow).bold())
+  }
+
   pub fn banner(self) -> Color {
     self.restyle(Style::new().fg(Cyan).bold())
   }
diff --git a/src/justfile.rs b/src/justfile.rs
index 8905e9c879..f86bde36fe 100644
--- a/src/justfile.rs
+++ b/src/justfile.rs
@@ -6,6 +6,7 @@ pub struct Justfile<'a> {
   pub assignments: BTreeMap<&'a str, Expression<'a>>,
   pub exports: BTreeSet<&'a str>,
   pub aliases: BTreeMap<&'a str, Alias<'a>>,
+  pub deprecated_equals: bool,
 }
 
 impl<'a> Justfile<'a> where {
@@ -80,7 +81,7 @@ impl<'a> Justfile<'a> where {
       }
 
       for (name, value) in scope {
-        println!("{0:1$} = \"{2}\"", name, width, value);
+        println!("{0:1$} := \"{2}\"", name, width, value);
       }
       return Ok(());
     }
@@ -175,7 +176,7 @@ impl<'a> Display for Justfile<'a> {
       if self.exports.contains(name) {
         write!(f, "export ")?;
       }
-      write!(f, "{} = {}", name, expression)?;
+      write!(f, "{} := {}", name, expression)?;
       items -= 1;
       if items != 0 {
         write!(f, "\n\n")?;
diff --git a/src/lexer.rs b/src/lexer.rs
index 63a11b0061..2927a22fd5 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -323,7 +323,7 @@ impl<'a> Lexer<'a> {
       '@' => self.lex_single(At),
       '=' => self.lex_single(Equals),
       ',' => self.lex_single(Comma),
-      ':' => self.lex_single(Colon),
+      ':' => self.lex_colon(),
       '(' => self.lex_single(ParenL),
       ')' => self.lex_single(ParenR),
       '{' => self.lex_brace_l(),
@@ -442,6 +442,20 @@ impl<'a> Lexer<'a> {
     Ok(())
   }
 
+  /// Lex a token starting with ':'
+  fn lex_colon(&mut self) -> CompilationResult<'a, ()> {
+    self.advance()?;
+
+    if let Some('=') = self.next {
+      self.advance()?;
+      self.token(ColonEquals);
+    } else {
+      self.token(Colon);
+    }
+
+    Ok(())
+  }
+
   /// Lex a token starting with '{'
   fn lex_brace_l(&mut self) -> CompilationResult<'a, ()> {
     if !self.rest_starts_with("{{") {
diff --git a/src/parser.rs b/src/parser.rs
index 939b12ccc0..0b6e7b68c7 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -12,6 +12,7 @@ pub struct Parser<'a> {
   exports: BTreeSet<&'a str>,
   aliases: BTreeMap<&'a str, Alias<'a>>,
   alias_tokens: BTreeMap<&'a str, Token<'a>>,
+  deprecated_equals: bool,
 }
 
 impl<'a> Parser<'a> {
@@ -31,6 +32,7 @@ impl<'a> Parser<'a> {
       exports: empty(),
       aliases: empty(),
       alias_tokens: empty(),
+      deprecated_equals: false,
       text,
     }
   }
@@ -152,10 +154,10 @@ impl<'a> Parser<'a> {
     }
 
     if let Some(token) = self.expect(Colon) {
-      // if we haven't accepted any parameters, an equals
+      // if we haven't accepted any parameters, a :=
       // would have been fine as part of an assignment
       if parameters.is_empty() {
-        return Err(self.unexpected_token(&token, &[Name, Plus, Colon, Equals]));
+        return Err(self.unexpected_token(&token, &[Name, Plus, Colon, ColonEquals]));
       } else {
         return Err(self.unexpected_token(&token, &[Name, Plus, Colon]));
       }
@@ -420,6 +422,10 @@ impl<'a> Parser<'a> {
             if token.lexeme() == "export" {
               let next = self.tokens.next().unwrap();
               if next.kind == Name && self.accepted(Equals) {
+                self.deprecated_equals = true;
+                self.assignment(next, true)?;
+                doc = None;
+              } else if next.kind == Name && self.accepted(ColonEquals) {
                 self.assignment(next, true)?;
                 doc = None;
               } else {
@@ -430,6 +436,10 @@ impl<'a> Parser<'a> {
             } else if token.lexeme() == "alias" {
               let next = self.tokens.next().unwrap();
               if next.kind == Name && self.accepted(Equals) {
+                self.deprecated_equals = true;
+                self.alias(next)?;
+                doc = None;
+              } else if next.kind == Name && self.accepted(ColonEquals) {
                 self.alias(next)?;
                 doc = None;
               } else {
@@ -438,6 +448,10 @@ impl<'a> Parser<'a> {
                 doc = None;
               }
             } else if self.accepted(Equals) {
+              self.deprecated_equals = true;
+              self.assignment(token, false)?;
+              doc = None;
+            } else if self.accepted(ColonEquals) {
               self.assignment(token, false)?;
               doc = None;
             } else {
@@ -501,6 +515,7 @@ impl<'a> Parser<'a> {
       assignments: self.assignments,
       exports: self.exports,
       aliases: self.aliases,
+      deprecated_equals: self.deprecated_equals,
     })
   }
 }
@@ -604,10 +619,10 @@ foo a='b\t':
   summary_test! {
     parse_export,
     r#"
-export a = "hello"
+export a := "hello"
 
   "#,
-    r#"export a = "hello""#,
+    r#"export a := "hello""#,
   }
 
   summary_test! {
@@ -615,9 +630,9 @@ export a = "hello"
     r#"
 foo:
   echo a
-alias f = foo
+alias f := foo
 "#,
-r#"alias f = foo
+r#"alias f := foo
 
 foo:
     echo a"#
@@ -626,11 +641,11 @@ foo:
   summary_test! {
   parse_alias_before_target,
     r#"
-alias f = foo
+alias f := foo
 foo:
   echo a
 "#,
-r#"alias f = foo
+r#"alias f := foo
 
 foo:
     echo a"#
@@ -639,11 +654,11 @@ foo:
   summary_test! {
   parse_alias_with_comment,
     r#"
-alias f = foo #comment
+alias f := foo #comment
 foo:
   echo a
 "#,
-r#"alias f = foo
+r#"alias f := foo
 
 foo:
     echo a"#
@@ -655,9 +670,9 @@ foo:
 x:
 y:
 z:
-foo = \"xx\"
-bar = foo
-goodbye = \"y\"
+foo := \"xx\"
+bar := foo
+goodbye := \"y\"
 hello a b    c   : x y    z #hello
   #! blah
   #blarg
@@ -666,11 +681,11 @@ hello a b    c   : x y    z #hello
   2
   3
 ",
-    "bar = foo
+    "bar := foo
 
-foo = \"xx\"
+foo := \"xx\"
 
-goodbye = \"y\"
+goodbye := \"y\"
 
 hello a b c: x y z
     #! blah
@@ -690,14 +705,14 @@ z:"
   summary_test! {
   parse_shebang,
     "
-practicum = 'hello'
+practicum := 'hello'
 install:
 \t#!/bin/sh
 \tif [[ -f {{practicum}} ]]; then
 \t\treturn
 \tfi
 ",
-    "practicum = 'hello'
+    "practicum := 'hello'
 
 install:
     #!/bin/sh
@@ -714,27 +729,27 @@ install:
 
   summary_test! {
   parse_assignments,
-    r#"a = "0"
-c = a + b + a + b
-b = "1"
+    r#"a := "0"
+c := a + b + a + b
+b := "1"
 "#,
-    r#"a = "0"
+    r#"a := "0"
 
-b = "1"
+b := "1"
 
-c = a + b + a + b"#,
+c := a + b + a + b"#,
   }
 
   summary_test! {
   parse_assignment_backticks,
-    "a = `echo hello`
-c = a + b + a + b
-b = `echo goodbye`",
-    "a = `echo hello`
+    "a := `echo hello`
+c := a + b + a + b
+b := `echo goodbye`",
+    "a := `echo hello`
 
-b = `echo goodbye`
+b := `echo goodbye`
 
-c = a + b + a + b",
+c := a + b + a + b",
   }
 
   summary_test! {
@@ -753,14 +768,14 @@ c = a + b + a + b",
 
   summary_test! {
     string_quote_escape,
-    r#"a = "hello\"""#,
-    r#"a = "hello\"""#,
+    r#"a := "hello\"""#,
+    r#"a := "hello\"""#,
   }
 
   summary_test! {
     string_escapes,
-    r#"a = "\n\t\r\"\\""#,
-    r#"a = "\n\t\r\"\\""#,
+    r#"a := "\n\t\r\"\\""#,
+    r#"a := "\n\t\r\"\\""#,
   }
 
   summary_test! {
@@ -774,11 +789,11 @@ c = a + b + a + b",
   summary_test! {
   unary_functions,
     "
-x = arch()
+x := arch()
 
 a:
   {{os()}} {{os_family()}}",
-    "x = arch()
+    "x := arch()
 
 a:
     {{os()}} {{os_family()}}",
@@ -787,11 +802,11 @@ a:
   summary_test! {
   env_functions,
     r#"
-x = env_var('foo',)
+x := env_var('foo',)
 
 a:
   {{env_var_or_default('foo' + 'bar', 'baz',)}} {{env_var(env_var("baz"))}}"#,
-    r#"x = env_var('foo')
+    r#"x := env_var('foo')
 
 a:
     {{env_var_or_default('foo' + 'bar', 'baz')}} {{env_var(env_var("baz"))}}"#,
@@ -832,10 +847,10 @@ f x=(`echo hello` + "foo"):
   summary_test! {
     parameter_default_concatination_variable,
     r#"
-x = "10"
+x := "10"
 f y=(`echo hello` + x) +z="foo":
 "#,
-    r#"x = "10"
+    r#"x := "10"
 
 f y=(`echo hello` + x) +z="foo":"#,
   }
@@ -843,24 +858,24 @@ f y=(`echo hello` + x) +z="foo":"#,
   summary_test! {
     parameter_default_multiple,
     r#"
-x = "10"
+x := "10"
 f y=(`echo hello` + x) +z=("foo" + "bar"):
 "#,
-    r#"x = "10"
+    r#"x := "10"
 
 f y=(`echo hello` + x) +z=("foo" + "bar"):"#,
   }
 
   summary_test! {
     concatination_in_group,
-    "x = ('0' + '1')",
-    "x = ('0' + '1')",
+    "x := ('0' + '1')",
+    "x := ('0' + '1')",
   }
 
   summary_test! {
     string_in_group,
-    "x = ('0'   )",
-    "x = ('0')",
+    "x := ('0'   )",
+    "x := ('0')",
   }
 
   #[rustfmt::skip]
diff --git a/src/run.rs b/src/run.rs
index 132e772043..14e899c238 100644
--- a/src/run.rs
+++ b/src/run.rs
@@ -321,6 +321,24 @@ pub fn run() {
     }
   });
 
+  if justfile.deprecated_equals {
+    let warning = color.warning().stderr();
+    let message = color.message().stderr();
+
+    eprintln!(
+      "{}",
+      warning.paint(
+        "warning: `=` in assignments, exports, and aliases is being phased out on favor of `:=`"
+      )
+    );
+
+    eprintln!(
+      "{}",
+      message
+        .paint("Please see this issue for more details: https://github.com/casey/just/issues/379")
+    );
+  }
+
   if matches.is_present("SUMMARY") {
     if justfile.count() == 0 {
       eprintln!("Justfile contains no recipes.");
diff --git a/src/testing.rs b/src/testing.rs
index 03c5a464bb..773e2ee2dd 100644
--- a/src/testing.rs
+++ b/src/testing.rs
@@ -16,6 +16,7 @@ pub fn token_summary(tokens: &[Token]) -> String {
       At => "@",
       Backtick => "`",
       Colon => ":",
+      ColonEquals => ":=",
       Comma => ",",
       Comment => "#",
       Dedent => "<",
diff --git a/src/token_kind.rs b/src/token_kind.rs
index 23cda3d6c0..08e4f22621 100644
--- a/src/token_kind.rs
+++ b/src/token_kind.rs
@@ -5,6 +5,7 @@ pub enum TokenKind {
   At,
   Backtick,
   Colon,
+  ColonEquals,
   Comma,
   Comment,
   Dedent,
@@ -35,6 +36,7 @@ impl Display for TokenKind {
         At => "'@'",
         Backtick => "backtick",
         Colon => "':'",
+        ColonEquals => "':='",
         Comma => "','",
         Comment => "comment",
         Dedent => "dedent",
diff --git a/tests/integration.rs b/tests/integration.rs
index 33b8db355b..8d1526824d 100644
--- a/tests/integration.rs
+++ b/tests/integration.rs
@@ -157,7 +157,7 @@ fn integration_test(
 
 integration_test! {
   name: alias_listing,
-  justfile: "foo:\n  echo foo\nalias f = foo",
+  justfile: "foo:\n  echo foo\nalias f := foo",
   args: ("--list"),
   stdin:  "",
   stdout: "Available recipes:
@@ -170,7 +170,7 @@ integration_test! {
 
 integration_test! {
   name: alias_listing_multiple_aliases,
-  justfile: "foo:\n  echo foo\nalias f = foo\nalias fo = foo",
+  justfile: "foo:\n  echo foo\nalias f := foo\nalias fo := foo",
   args: ("--list"),
   stdin:  "",
   stdout: "Available recipes:
@@ -184,7 +184,7 @@ integration_test! {
 
 integration_test! {
   name: alias_listing_parameters,
-  justfile: "foo PARAM='foo':\n  echo {{PARAM}}\nalias f = foo",
+  justfile: "foo PARAM='foo':\n  echo {{PARAM}}\nalias f := foo",
   args: ("--list"),
   stdin:  "",
   stdout: "Available recipes:
@@ -197,7 +197,7 @@ integration_test! {
 
 integration_test! {
   name: alias_listing_private,
-  justfile: "foo PARAM='foo':\n  echo {{PARAM}}\nalias _f = foo",
+  justfile: "foo PARAM='foo':\n  echo {{PARAM}}\nalias _f := foo",
   args: ("--list"),
   stdin:  "",
   stdout: "Available recipes:
@@ -209,7 +209,7 @@ integration_test! {
 
 integration_test! {
   name: alias,
-  justfile: "foo:\n  echo foo\nalias f = foo",
+  justfile: "foo:\n  echo foo\nalias f := foo",
   args: ("f"),
   stdin:  "",
   stdout: "foo\n",
@@ -219,7 +219,7 @@ integration_test! {
 
 integration_test! {
   name: alias_with_parameters,
-  justfile: "foo value='foo':\n  echo {{value}}\nalias f = foo",
+  justfile: "foo value='foo':\n  echo {{value}}\nalias f := foo",
   args: ("f", "bar"),
   stdin:  "",
   stdout: "bar\n",
@@ -229,7 +229,7 @@ integration_test! {
 
 integration_test! {
   name: alias_with_dependencies,
-  justfile: "foo:\n  echo foo\nbar: foo\nalias b = bar",
+  justfile: "foo:\n  echo foo\nbar: foo\nalias b := bar",
   args: ("b"),
   stdin:  "",
   stdout: "foo\n",
@@ -239,13 +239,13 @@ integration_test! {
 
 integration_test! {
   name: duplicate_alias,
-  justfile: "alias foo = bar\nalias foo = baz\n",
+  justfile: "alias foo := bar\nalias foo := baz\n",
   args: (),
   stdin:  "",
   stdout: "" ,
   stderr: "error: Alias `foo` first defined on line `1` is redefined on line `2`
   |
-2 | alias foo = baz
+2 | alias foo := baz
   |       ^^^
 ",
   status: EXIT_FAILURE,
@@ -253,13 +253,13 @@ integration_test! {
 
 integration_test! {
   name: unknown_alias_target,
-  justfile: "alias foo = bar\n",
+  justfile: "alias foo := bar\n",
   args: (),
   stdin:  "",
   stdout: "",
   stderr: "error: Alias `foo` has an unknown target `bar`
   |
-1 | alias foo = bar
+1 | alias foo := bar
   |       ^^^
 ",
   status: EXIT_FAILURE,
@@ -267,13 +267,13 @@ integration_test! {
 
 integration_test! {
   name: alias_shadows_recipe,
-  justfile: "bar:\n  echo bar\nalias foo = bar\nfoo:\n  echo foo",
+  justfile: "bar:\n  echo bar\nalias foo := bar\nfoo:\n  echo foo",
   args: (),
   stdin:  "",
   stdout: "",
   stderr: "error: Alias `foo` defined on `3` shadows recipe defined on `4`
   |
-3 | alias foo = bar
+3 | alias foo := bar
   |       ^^^
 ",
   status: EXIT_FAILURE,
@@ -387,8 +387,8 @@ c:
 
 integration_test! {
   name:     show,
-  justfile: r#"hello = "foo"
-bar = hello + hello
+  justfile: r#"hello := "foo"
+bar := hello + hello
 recipe:
  echo {{hello + "bar" + bar}}"#,
   args:     ("--show", "recipe"),
@@ -431,7 +431,7 @@ integration_test! {
 
 integration_test! {
   name:     backtick_success,
-  justfile: "a = `printf Hello,`\nbar:\n printf '{{a + `printf ' world.'`}}'",
+  justfile: "a := `printf Hello,`\nbar:\n printf '{{a + `printf ' world.'`}}'",
   args:     (),
   stdin:    "",
   stdout:   "Hello, world.",
@@ -441,7 +441,7 @@ integration_test! {
 
 integration_test! {
   name:     backtick_trimming,
-  justfile: "a = `echo Hello,`\nbar:\n echo '{{a + `echo ' world.'`}}'",
+  justfile: "a := `echo Hello,`\nbar:\n echo '{{a + `echo ' world.'`}}'",
   args:     (),
   stdin:    "",
   stdout:   "Hello, world.\n",
@@ -451,21 +451,21 @@ integration_test! {
 
 integration_test! {
   name:     backtick_code_assignment,
-  justfile: "b = a\na = `exit 100`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "b := a\na := `exit 100`\nbar:\n echo '{{`exit 200`}}'",
   args:     (),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Backtick failed with exit code 100
   |
-2 | a = `exit 100`
-  |     ^^^^^^^^^^
+2 | a := `exit 100`
+  |      ^^^^^^^^^^
 ",
   status:   100,
 }
 
 integration_test! {
   name:     backtick_code_interpolation,
-  justfile: "b = a\na = `echo hello`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "b := a\na := `echo hello`\nbar:\n echo '{{`exit 200`}}'",
   args:     (),
   stdin:    "",
   stdout:   "",
@@ -477,7 +477,6 @@ integration_test! {
   status:   200,
 }
 
-// 😬鎌
 integration_test! {
   name:     backtick_code_interpolation_mod,
   justfile: "f:\n 無{{`exit 200`}}",
@@ -579,7 +578,7 @@ backtick-fail:
 
 integration_test! {
   name:     backtick_code_long,
-  justfile: "\n\n\n\n\n\nb = a\na = `echo hello`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "\n\n\n\n\n\nb := a\na := `echo hello`\nbar:\n echo '{{`exit 200`}}'",
   args:     (),
   stdin:    "",
   stdout:   "",
@@ -629,14 +628,14 @@ integration_test! {
   justfile: "foo:
  echo hello
  echo {{`exit 111`}}
-a = `exit 222`",
+a := `exit 222`",
   args:     (),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Backtick failed with exit code 222
   |
-4 | a = `exit 222`
-  |     ^^^^^^^^^^
+4 | a := `exit 222`
+  |      ^^^^^^^^^^
 ",
   status:   222,
 }
@@ -646,7 +645,7 @@ integration_test! {
   justfile: "foo:
  echo hello
  echo {{`exit 111`}}
-a = `exit 222`",
+a := `exit 222`",
   args:     ("--set", "foo", "bar", "--set", "baz", "bob", "--set", "a", "b", "a", "b"),
   stdin:    "",
   stdout:   "",
@@ -660,7 +659,7 @@ integration_test! {
   justfile: "foo:
  echo hello
  echo {{`exit 111`}}
-a = `exit 222`",
+a := `exit 222`",
   args:     ("foo=bar", "baz=bob", "a=b", "a", "b"),
   stdin:    "",
   stdout:   "",
@@ -674,7 +673,7 @@ integration_test! {
   justfile: "foo:
  echo hello
  echo {{`exit 111`}}
-a = `exit 222`",
+a := `exit 222`",
   args:     ("foo=bar", "a=b", "a", "b"),
   stdin:    "",
   stdout:   "",
@@ -685,9 +684,9 @@ a = `exit 222`",
 integration_test! {
   name:     overrides_first,
   justfile: r#"
-foo = "foo"
-a = "a"
-baz = "baz"
+foo := "foo"
+a := "a"
+baz := "baz"
 
 recipe arg:
  echo arg={{arg}}
@@ -702,9 +701,9 @@ recipe arg:
 integration_test! {
   name:     overrides_not_evaluated,
   justfile: r#"
-foo = `exit 1`
-a = "a"
-baz = "baz"
+foo := `exit 1`
+a := "a"
+baz := "baz"
 
 recipe arg:
  echo arg={{arg}}
@@ -719,7 +718,7 @@ recipe arg:
 integration_test! {
   name:     dry_run,
   justfile: r#"
-var = `echo stderr 1>&2; echo backtick`
+var := `echo stderr 1>&2; echo backtick`
 
 command:
   @touch /this/is/not/a/file
@@ -748,20 +747,20 @@ echo `echo command interpolation`
 integration_test! {
   name:     evaluate,
   justfile: r#"
-foo = "a\t"
-hello = "c"
-bar = "b\t"
-ab = foo + bar + hello
+foo := "a\t"
+hello := "c"
+bar := "b\t"
+ab := foo + bar + hello
 
 wut:
   touch /this/is/not/a/file
 "#,
   args:     ("--evaluate"),
   stdin:    "",
-  stdout:   r#"ab    = "a	b	c"
-bar   = "b	"
-foo   = "a	"
-hello = "c"
+  stdout:   r#"ab    := "a	b	c"
+bar   := "b	"
+foo   := "a	"
+hello := "c"
 "#,
   stderr:   "",
   status:   EXIT_SUCCESS,
@@ -770,10 +769,10 @@ hello = "c"
 integration_test! {
   name:     export_success,
   justfile: r#"
-export FOO = "a"
-baz = "c"
-export BAR = "b"
-export ABC = FOO + BAR + baz
+export FOO := "a"
+baz := "c"
+export BAR := "b"
+export ABC := FOO + BAR + baz
 
 wut:
   echo $FOO $BAR $ABC
@@ -788,10 +787,10 @@ wut:
 integration_test! {
   name:     export_override,
   justfile: r#"
-export FOO = "a"
-baz = "c"
-export BAR = "b"
-export ABC = FOO + "-" + BAR + "-" + baz
+export FOO := "a"
+baz := "c"
+export BAR := "b"
+export ABC := FOO + "-" + BAR + "-" + baz
 
 wut:
   echo $FOO $BAR $ABC
@@ -806,10 +805,10 @@ wut:
 integration_test! {
   name:     export_shebang,
   justfile: r#"
-export FOO = "a"
-baz = "c"
-export BAR = "b"
-export ABC = FOO + BAR + baz
+export FOO := "a"
+baz := "c"
+export BAR := "b"
+export ABC := FOO + BAR + baz
 
 wut:
   #!/bin/sh
@@ -825,7 +824,7 @@ wut:
 integration_test! {
   name:     export_recipe_backtick,
   justfile: r#"
-export EXPORTED_VARIABLE = "A-IS-A"
+export EXPORTED_VARIABLE := "A-IS-A"
 
 recipe:
   echo {{`echo recipe $EXPORTED_VARIABLE`}}
@@ -840,7 +839,7 @@ recipe:
 integration_test! {
   name:     raw_string,
   justfile: r#"
-export EXPORTED_VARIABLE = '\z'
+export EXPORTED_VARIABLE := '\z'
 
 recipe:
   printf "$EXPORTED_VARIABLE"
@@ -931,7 +930,7 @@ default:
 integration_test! {
   name:     quiet_flag_no_assignment_backtick_stderr,
   justfile: r#"
-a = `echo hello 1>&2`
+a := `echo hello 1>&2`
 default:
   exit 100
 "#,
@@ -1056,39 +1055,39 @@ integration_test! {
 
 integration_test! {
   name:     color_always,
-  justfile: "b = a\na = `exit 100`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "b := a\na := `exit 100`\nbar:\n echo '{{`exit 200`}}'",
   args:     ("--color", "always"),
   stdin:    "",
   stdout:   "",
   stderr:   "\u{1b}[1;31merror:\u{1b}[0m \u{1b}[1mBacktick failed with exit code 100
-\u{1b}[0m  |\n2 | a = `exit 100`\n  |     \u{1b}[1;31m^^^^^^^^^^\u{1b}[0m\n",
+\u{1b}[0m  |\n2 | a := `exit 100`\n  |      \u{1b}[1;31m^^^^^^^^^^\u{1b}[0m\n",
   status:   100,
 }
 
 integration_test! {
   name:     color_never,
-  justfile: "b = a\na = `exit 100`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "b := a\na := `exit 100`\nbar:\n echo '{{`exit 200`}}'",
   args:     ("--color", "never"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Backtick failed with exit code 100
   |
-2 | a = `exit 100`
-  |     ^^^^^^^^^^
+2 | a := `exit 100`
+  |      ^^^^^^^^^^
 ",
   status:   100,
 }
 
 integration_test! {
   name:     color_auto,
-  justfile: "b = a\na = `exit 100`\nbar:\n echo '{{`exit 200`}}'",
+  justfile: "b := a\na := `exit 100`\nbar:\n echo '{{`exit 200`}}'",
   args:     ("--color", "auto"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Backtick failed with exit code 100
   |
-2 | a = `exit 100`
-  |     ^^^^^^^^^^
+2 | a := `exit 100`
+  |      ^^^^^^^^^^
 ",
   status:   100,
 }
@@ -1432,9 +1431,9 @@ foo:
 integration_test! {
   name:     test_os_arch_functions_in_expression,
   justfile: r#"
-a = arch()
-o = os()
-f = os_family()
+a := arch()
+o := os()
+f := os_family()
 
 foo:
   echo {{a}} {{o}} {{f}}
@@ -1450,9 +1449,9 @@ foo:
 integration_test! {
   name:     env_var_functions,
   justfile: r#"
-p = env_var('USER')
-b = env_var_or_default('ZADDY', 'HTAP')
-x = env_var_or_default('XYZ', 'ABC')
+p := env_var('USER')
+b := env_var_or_default('ZADDY', 'HTAP')
+x := env_var_or_default('XYZ', 'ABC')
 
 foo:
   /bin/echo '{{p}}' '{{b}}' '{{x}}'
@@ -1468,9 +1467,9 @@ foo:
 integration_test! {
   name:     env_var_functions,
   justfile: r#"
-p = env_var('USERNAME')
-b = env_var_or_default('ZADDY', 'HTAP')
-x = env_var_or_default('XYZ', 'ABC')
+p := env_var('USERNAME')
+b := env_var_or_default('ZADDY', 'HTAP')
+x := env_var_or_default('XYZ', 'ABC')
 
 foo:
   /bin/echo '{{p}}' '{{b}}' '{{x}}'
@@ -1573,7 +1572,7 @@ c: b a
 
 integration_test! {
   name:     parameter_shadows_variable,
-  justfile: "FOO = 'hello'\na FOO:",
+  justfile: "FOO := 'hello'\na FOO:",
   args:     ("a"),
   stdin:    "",
   stdout:   "",
@@ -1587,15 +1586,15 @@ integration_test! {
 
 integration_test! {
   name:     unknown_function_in_assignment,
-  justfile: r#"foo = foo() + "hello"
+  justfile: r#"foo := foo() + "hello"
 bar:"#,
   args:     ("bar"),
   stdin:    "",
   stdout:   "",
   stderr:   r#"error: Call to unknown function `foo`
   |
-1 | foo = foo() + "hello"
-  |       ^^^
+1 | foo := foo() + "hello"
+  |        ^^^
 "#,
   status:   EXIT_FAILURE,
 }
@@ -1659,13 +1658,13 @@ integration_test! {
 
 integration_test! {
   name:     duplicate_variable,
-  justfile: "a = 'hello'\na = 'hello'\nfoo:",
+  justfile: "a := 'hello'\na := 'hello'\nfoo:",
   args:     ("foo"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Variable `a` has multiple definitions
   |
-2 | a = 'hello'
+2 | a := 'hello'
   | ^
 ",
   status:   EXIT_FAILURE,
@@ -1691,7 +1690,7 @@ integration_test! {
   args:     ("foo"),
   stdin:    "",
   stdout:   "",
-  stderr:   "error: Expected name, '+', ':', or '=', but found raw string
+  stderr:   "error: Expected name, '+', ':', or ':=', but found raw string
   |
 1 | foo 'bar'
   |     ^^^^^
@@ -1729,13 +1728,13 @@ integration_test! {
 
 integration_test! {
   name:     variable_self_dependency,
-  justfile: "z = z\na:",
+  justfile: "z := z\na:",
   args:     ("a"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Variable `z` is defined in terms of itself
   |
-1 | z = z
+1 | z := z
   | ^
 ",
   status:   EXIT_FAILURE,
@@ -1743,13 +1742,13 @@ integration_test! {
 
 integration_test! {
   name:     variable_circular_dependency,
-  justfile: "x = y\ny = z\nz = x\na:",
+  justfile: "x := y\ny := z\nz := x\na:",
   args:     ("a"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: Variable `x` depends on its own value: `x -> y -> z -> x`
   |
-1 | x = y
+1 | x := y
   | ^
 ",
   status:   EXIT_FAILURE,
@@ -1757,15 +1756,15 @@ integration_test! {
 
 integration_test! {
   name:     invalid_escape_sequence,
-  justfile: r#"x = "\q"
+  justfile: r#"x := "\q"
 a:"#,
   args:     ("a"),
   stdin:    "",
   stdout:   "",
   stderr:   "error: `\\q` is not a valid escape sequence
   |
-1 | x = \"\\q\"
-  |     ^^^^
+1 | x := \"\\q\"
+  |      ^^^^
 ",
   status:   EXIT_FAILURE,
 }
@@ -1773,7 +1772,7 @@ a:"#,
 integration_test! {
   name:     multiline_raw_string,
   justfile: "
-string = 'hello
+string := 'hello
 whatever'
 
 a:
@@ -1793,7 +1792,7 @@ whatever'
 integration_test! {
   name:     error_line_after_multiline_raw_string,
   justfile: "
-string = 'hello
+string := 'hello
 
 whatever' + 'yo'
 
@@ -1814,7 +1813,7 @@ a:
 integration_test! {
   name:     error_column_after_multiline_raw_string,
   justfile: "
-string = 'hello
+string := 'hello
 
 whatever' + bar
 
@@ -2039,7 +2038,7 @@ integration_test! {
    name:     comment_before_variable,
    justfile: "
 #
-A='1'
+A:='1'
 echo:
   echo {{A}}
  ",
@@ -2068,7 +2067,7 @@ integration_test! {
    name:     dotenv_variable_in_backtick,
    justfile: "
 #
-X=`echo $DOTENV_KEY`
+X:=`echo $DOTENV_KEY`
 echo:
   echo {{X}}
  ",
@@ -2097,8 +2096,8 @@ integration_test! {
    name:     dotenv_variable_in_function_in_backtick,
    justfile: "
 #
-X=env_var_or_default('DOTENV_KEY', 'foo')
-Y=env_var('DOTENV_KEY')
+X:=env_var_or_default('DOTENV_KEY', 'foo')
+Y:=env_var('DOTENV_KEY')
 echo:
   echo {{X}}
   echo {{Y}}
@@ -2113,15 +2112,15 @@ echo:
 integration_test! {
    name:     invalid_escape_sequence_message,
    justfile: r#"
-X = "\'"
+X := "\'"
 "#,
    args:     (),
    stdin:    "",
    stdout:   "",
    stderr:   r#"error: `\'` is not a valid escape sequence
   |
-2 | X = "\'"
-  |     ^^^^
+2 | X := "\'"
+  |      ^^^^
 "#,
    status:   EXIT_FAILURE,
 }
@@ -2200,7 +2199,7 @@ foo x=`echo foo`:
 integration_test! {
    name:     default_variable,
    justfile: "
-y = 'foo'
+y := 'foo'
 foo x=y:
   echo {{x}}
 ",
@@ -2292,7 +2291,7 @@ assembly_source_files = $(wildcard src/arch/$(arch)/*.s)
 integration_test! {
    name:     backtick_variable_cat,
    justfile: "
-stdin = `cat`
+stdin := `cat`
 
 default:
   echo {{stdin}}
@@ -2338,7 +2337,7 @@ default stdin = `cat justfile`:
 integration_test! {
    name:     backtick_variable_read_single,
    justfile: "
-password = `read PW && echo $PW`
+password := `read PW && echo $PW`
 
 default:
   echo {{password}}
@@ -2353,8 +2352,8 @@ default:
 integration_test! {
    name:     backtick_variable_read_multiple,
    justfile: "
-a = `read A && echo $A`
-b = `read B && echo $B`
+a := `read A && echo $A`
+b := `read B && echo $B`
 
 default:
   echo {{a}}
@@ -2381,3 +2380,63 @@ default a=`read A && echo $A` b=`read B && echo $B`:
    stderr:   "echo foo\necho bar\n",
    status:   EXIT_SUCCESS,
 }
+
+integration_test! {
+   name:     equals_deprecated_assignment,
+   justfile: "
+
+foo = 'bar'
+
+default:
+  echo {{foo}}
+
+",
+   args:     (),
+   stdin:    "",
+   stdout:   "bar\n",
+   stderr:   "warning: `=` in assignments, exports, and aliases is being phased out on favor of `:=`
+Please see this issue for more details: https://github.com/casey/just/issues/379
+echo bar
+",
+   status:   EXIT_SUCCESS,
+}
+
+integration_test! {
+   name:     equals_deprecated_export,
+   justfile: "
+
+export FOO = 'bar'
+
+default:
+  echo $FOO
+
+",
+   args:     (),
+   stdin:    "",
+   stdout:   "bar\n",
+   stderr:   "warning: `=` in assignments, exports, and aliases is being phased out on favor of `:=`
+Please see this issue for more details: https://github.com/casey/just/issues/379
+echo $FOO
+",
+   status:   EXIT_SUCCESS,
+}
+
+integration_test! {
+   name:     equals_deprecated_alias,
+   justfile: "
+
+alias foo = default
+
+default:
+  echo default
+
+",
+   args:     ("foo"),
+   stdin:    "",
+   stdout:   "default\n",
+   stderr:   "warning: `=` in assignments, exports, and aliases is being phased out on favor of `:=`
+Please see this issue for more details: https://github.com/casey/just/issues/379
+echo default
+",
+   status:   EXIT_SUCCESS,
+}