Squashed commit of the following:

commit 95479c8ad744db48386a5c78e54ef8da80e9120b
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Apr 28 12:26:32 2021 -0400

    chore(version): bump version to 4.2.1

commit 6956f51cae
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Apr 28 12:24:21 2021 -0400

    fix(Makefile): `vendor-update`

    Update the `vendor-update` build target to run `go mod vendor` after
    updating dependencies.

commit 0aca411279
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Apr 28 12:23:24 2021 -0400

    chore(deps): update dependencies

commit e847956b02
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Apr 28 08:26:51 2021 -0400

    chore(deps): build updates

    - Upgrade `go` to `1.16.3`

    - Attempt to fix build errors regarding dependencies

vendor/github.com/alecthomas/chroma/lexers/n/nasm.go

@@ -6,7 +6,7 @@ import (
 )
 
 // Nasm lexer.
-var Nasm = internal.Register(MustNewLexer(
+var Nasm = internal.Register(MustNewLazyLexer(
 	&Config{
 		Name:            "NASM",
 		Aliases:         []string{"nasm"},
@@ -14,7 +14,11 @@ var Nasm = internal.Register(MustNewLexer(
 		MimeTypes:       []string{"text/x-nasm"},
 		CaseInsensitive: true,
 	},
-	Rules{
+	nasmRules,
+))
+
+func nasmRules() Rules {
+	return Rules{
 		"root": {
 			{`^\s*%`, CommentPreproc, Push("preproc")},
 			Include("whitespace"),
@@ -55,5 +59,5 @@ var Nasm = internal.Register(MustNewLexer(
 			{`seg|wrt|strict`, OperatorWord, nil},
 			{`byte|[dq]?word`, KeywordType, nil},
 		},
-	},
-))
+	}
+}

vendor/github.com/alecthomas/chroma/lexers/n/newspeak.go

@@ -6,14 +6,18 @@ import (
 )
 
 // Newspeak lexer.
-var Newspeak = internal.Register(MustNewLexer(
+var Newspeak = internal.Register(MustNewLazyLexer(
 	&Config{
 		Name:      "Newspeak",
 		Aliases:   []string{"newspeak"},
 		Filenames: []string{"*.ns2"},
 		MimeTypes: []string{"text/x-newspeak"},
 	},
-	Rules{
+	newspeakRules,
+))
+
+func newspeakRules() Rules {
+	return Rules{
 		"root": {
 			{`\b(Newsqueak2)\b`, KeywordDeclaration, nil},
 			{`'[^']*'`, LiteralString, nil},
@@ -51,5 +55,5 @@ var Newspeak = internal.Register(MustNewLexer(
 			{`\s+`, Text, nil},
 			{`"[^"]*"`, Comment, nil},
 		},
-	},
-))
+	}
+}

vendor/github.com/alecthomas/chroma/lexers/n/nginx.go

@@ -6,14 +6,18 @@ import (
 )
 
 // Nginx Configuration File lexer.
-var Nginx = internal.Register(MustNewLexer(
+var Nginx = internal.Register(MustNewLazyLexer(
 	&Config{
 		Name:      "Nginx configuration file",
 		Aliases:   []string{"nginx"},
 		Filenames: []string{"nginx.conf"},
 		MimeTypes: []string{"text/x-nginx-conf"},
 	},
-	Rules{
+	nginxRules,
+))
+
+func nginxRules() Rules {
+	return Rules{
 		"root": {
 			{`(include)(\s+)([^\s;]+)`, ByGroups(Keyword, Text, Name), nil},
 			{`[^\s;#]+`, Keyword, Push("stmt")},
@@ -43,5 +47,5 @@ var Nginx = internal.Register(MustNewLexer(
 			{`\s+`, Text, nil},
 			{`[$;]`, Text, nil},
 		},
-	},
-))
+	}
+}

vendor/github.com/alecthomas/chroma/lexers/n/nim.go

@@ -6,7 +6,7 @@ import (
 )
 
 // Nim lexer.
-var Nim = internal.Register(MustNewLexer(
+var Nim = internal.Register(MustNewLazyLexer(
 	&Config{
 		Name:            "Nim",
 		Aliases:         []string{"nim", "nimrod"},
@@ -14,7 +14,11 @@ var Nim = internal.Register(MustNewLexer(
 		MimeTypes:       []string{"text/x-nim"},
 		CaseInsensitive: true,
 	},
-	Rules{
+	nimRules,
+))
+
+func nimRules() Rules {
+	return Rules{
 		"root": {
 			{`#\[[\s\S]*?\]#`, CommentMultiline, nil},
 			{`##.*$`, LiteralStringDoc, nil},
@@ -89,5 +93,5 @@ var Nim = internal.Register(MustNewLexer(
 			{`\'i(8|16)`, LiteralNumberInteger, nil},
 			Default(Pop(1)),
 		},
-	},
-))
+	}
+}

vendor/github.com/alecthomas/chroma/lexers/n/nix.go

@@ -7,18 +7,22 @@ import (
 	"github.com/alecthomas/chroma/lexers/internal"
 )
 
-// nixb matches right boundary of a nix word. Use it instead of \b.
-const nixb = `(?![a-zA-Z0-9_'-])`
-
 // Nix lexer.
-var Nix = internal.Register(MustNewLexer(
+var Nix = internal.Register(MustNewLazyLexer(
 	&Config{
 		Name:      "Nix",
 		Aliases:   []string{"nixos", "nix"},
 		Filenames: []string{"*.nix"},
 		MimeTypes: []string{"text/x-nix"},
 	},
-	Rules{
+	nixRules,
+))
+
+func nixRules() Rules {
+	// nixb matches right boundary of a nix word. Use it instead of \b.
+	const nixb = `(?![a-zA-Z0-9_'-])`
+
+	return Rules{
 		"root": {
 			Include("keywords"),
 			Include("builtins"),
@@ -118,5 +122,5 @@ var Nix = internal.Register(MustNewLexer(
 		"space": {
 			{`[ \t\r\n]+`, Text, nil},
 		},
-	},
-))
+	}
+}