diff --git a/rc/filetype/kotlin.kak b/rc/filetype/kotlin.kak
new file mode 100644
index 00000000..d583f645
--- /dev/null
+++ b/rc/filetype/kotlin.kak
@@ -0,0 +1,170 @@
+# References --------------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾‾‾
+# Team: Yerlan & Kirk Duncan
+#
+# Kotlin 2020, Keywords and Operators, v1.4.0, viewed 9 September 2020, https://kotlinlang.org/docs/reference/keyword-reference.html
+# Kdoc 2020, Documenting Kotlin Code, Block Tags, v1.4.0, viewed 9 September 2020, https://kotlinlang.org/docs/reference/kotlin-doc.html
+# Oracle 2020, Java Platform, Standard Edition & Java Development Kit, Version 14 API Specification, viewed 8 September 2020, https://docs.oracle.com/en/java/javase/14/docs/api/index.html
+#
+# File types --------------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾‾‾
+hook global BufCreate .*[.](kt|kts)  %{
+  set-option buffer filetype kotlin
+}
+
+# Initialization ----------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾‾‾‾‾‾‾
+hook global WinSetOption filetype=kotlin %{
+  require-module kotlin
+
+  set-option window static_words %opt{kotlin_static_words}
+
+  # cleanup trailing whitespaces when exiting insert mode
+  hook window ModeChange pop:insert:.* -group kotlin-trim-indent %{ try %{ execute-keys -draft <a-x>s^\h+$<ret>d } }
+  hook window InsertChar \n -group kotlin-indent kotlin-insert-on-new-line
+  hook window InsertChar \n -group kotlin-indent kotlin-indent-on-new-line
+  hook window InsertChar \{ -group kotlin-indent kotlin-indent-on-opening-curly-brace
+  hook window InsertChar \} -group kotlin-indent kotlin-indent-on-closing-curly-brace
+
+  hook -once -always window WinSetOption filetype=.* %{ remove-hooks window kotlin-.+ }
+}
+
+hook -group kotlin-highlighter global WinSetOption filetype=kotlin %{
+  add-highlighter window/kotlin ref kotlin
+  add-highlighter window/kdoc ref kdoc
+
+  hook -once -always window WinSetOption filetype=.* %{
+    remove-highlighter window/kotlin
+    remove-highlighter window/kdoc
+  }
+}
+
+hook global BufSetOption filetype=kotlin %{
+  require-module kotlin
+
+  set-option buffer comment_line '//'
+  set-option buffer comment_block_begin '/*'
+  set-option buffer comment_block_end '*/'
+
+  hook -once -always buffer BufSetOption filetype=.* %{ remove-hooks buffer kotlin-.+ }
+}
+
+# Module ------------------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾
+provide-module kotlin %§
+
+add-highlighter shared/kotlin regions
+add-highlighter shared/kotlin/code default-region group
+add-highlighter shared/kotlin/string region %{(?<!')"} %{(?<!\\)(\\\\)*"} fill string
+add-highlighter shared/kotlin/comment region /\* \*/ fill comment
+add-highlighter shared/kotlin/inline_documentation region /// $ fill documentation
+add-highlighter shared/kotlin/line_comment region // $ fill comment
+
+add-highlighter shared/kotlin/code/kotlin_annotations regex @\w+\b|\b\w+@(?=\{) 0:meta
+add-highlighter shared/kotlin/code/kotlin_identifiers regex \b(field|it)\b 1:variable
+add-highlighter shared/kotlin/code/kotlin_fields      regex \.([A-Za-z_][\w]*)\s*?\. 1:type
+
+# As at 15 March 2021, kotlin_method see: https://regex101.com/r/Mhy4HG/1
+add-highlighter shared/kotlin/code/kotlin_methods     regex ::([A-Za-z_][\w]*)|\.([A-Za-z_][\w]*)\s*?[\(\{]|\.([A-Za-z_][\w]*)[\s\)\}>](?=[^\(\{]) 1:function 2:function 3:function
+
+# Test suite functions: fun `this is a valid character function test`()
+add-highlighter shared/kotlin/code/kotlin_fun_tests   regex ^\h*?fun\s*?`(.[^<>\[\]\\\.]+?)`\h*?(?=\() 1:default+uF
+add-highlighter shared/kotlin/code/kotlin_delimiters  regex (\(|\)|\[|\]|\{|\}|\;|') 1:operator
+add-highlighter shared/kotlin/code/kotlin_operators   regex (\+|-|\*|&|=|\\|\?|%|\|-|!|\||->|\.|,|<|>|:|\^|/) 1:operator
+add-highlighter shared/kotlin/code/kotlin_numbers     regex \b((0(x|X)[0-9a-fA-F]*)|(([0-9]+\.?[0-9]*)|(\.[0-9]+))((e|E)(\+|-)?[0-9]+)?)([LlFf])?\b 0:value
+
+# Generics need improvement, as after a colon will match as a constant only.
+# val program: IOU = XXXX; val cat: DOG = XXXX. matches IOU or DOG as a
+# CONSTANT when it could be generics. See: https://regex101.com/r/VPO5LE/7
+add-highlighter shared/kotlin/code/kotlin_constants_and_generics regex ((?<==\h)\([A-Z][A-Z0-9_]+\b(?=[<:\;])|\b(?<!<)[A-Z][A-Z0-9_]+(?=[^>\)]))\b|\b((?<!=\s)(?<!\.)[A-Z]+\d*?(?![\(\;:])(?=[,\)>\s]))\b 1:meta 2:type
+
+add-highlighter shared/kotlin/code/kotlin_target regex @(delegate|field|file|get|param|property|receiver|set|setparam)(?=:) 0:meta
+add-highlighter shared/kotlin/code/kotlin_soft   regex \b(by|catch|constructor|dynamic|finally|get|import|init|set|where)\b 1:keyword
+add-highlighter shared/kotlin/code/kotlin_hard   regex \b(as|as\?|break|class|continue|do|else|false|for|fun|if|in|!in|interface|is|!is|null|object|package|return|super|this|throw|true|try|typealias|val|var|when|while)\b 1:keyword
+
+add-highlighter shared/kotlin/code/kotlin_modifier regex \b(actual|abstract|annotation|companion|const|crossinline|data|enum|expect|external|final|infix|inline|inner|internal|lateinit|noinline|open|operator|out|override|private|protected|public|reified|sealed|suspend|tailrec|vararg)\b(?=[\s\n]) 1:attribute
+
+add-highlighter shared/kotlin/code/kotlin_type regex \b(Annotation|Any|Boolean|BooleanArray|Byte|ByteArray|Char|Character|CharArray|CharSequence|Class|ClassLoader|Cloneable|Comparable|Compiler|DeprecationLevel|Double|DoubleArray|Enum|Float|FloatArray|Function|Int|IntArray|Integer|Lazy|LazyThreadSafetyMode|Long|LongArray|Math|Nothing|Number|Object|Package|Pair|Process|Runnable|Runtime|SecurityManager|Short|ShortArray|StackTraceElement|StrictMath|String|StringBuffer|System|Thread|ThreadGroup|ThreadLocal|Triple|Unit|Void)\b(?=[^<]) 1:type
+
+# Kdoc --------------------------------------------------------------------------------------------- #
+# ‾‾‾‾
+add-highlighter shared/kdoc group
+add-highlighter shared/kdoc/tag regex \*(?:\s+)?(@(author|constructor|exception|param|property|receiver|return|sample|see|since|suppress|throws))\b 1:default+ui
+
+# Discolour ---------------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾‾
+add-highlighter shared/kotlin/code/discolour regex ^(package|import)(?S)(.+) 2:default+fa
+
+# Commands ----------------------------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾
+define-command -hidden kotlin-insert-on-new-line %[
+  # copy // comments prefix and following white spaces
+  try %{ execute-keys -draft <semicolon><c-s>k<a-x> s ^\h*\K/{2,}\h* <ret> y<c-o>P<esc> }
+]
+
+define-command -hidden kotlin-indent-on-new-line %~
+  evaluate-commands -draft -itersel %<
+    # preserve previous line indent
+    try %{ execute-keys -draft <semicolon>K<a-&> }
+    # indent after lines ending with { or (
+    try %[ execute-keys -draft k<a-x> <a-k> [{(]\h*$ <ret> j<a-gt> ]
+    # cleanup trailing white spaces on the previous line
+    try %{ execute-keys -draft k<a-x> s \h+$ <ret>d }
+    # align to opening paren of previous line
+    try %{ execute-keys -draft [( <a-k> \A\([^\n]+\n[^\n]*\n?\z <ret> s \A\(\h*.|.\z <ret> '<a-;>' & }
+    # indent after a pattern match on when/where statements
+    try %[ execute-keys -draft k<a-x> <a-k> ^\h*(when|where).*$ <ret> j<a-gt> ]
+    # indent after term on an expression
+    try %[ execute-keys -draft k<a-x> <a-k> =\h*?$ <ret> j<a-gt> ]
+    # indent after keywords
+    try %[ execute-keys -draft <semicolon><a-F>)MB <a-k> \A(catch|do|else|for|if|try|while)\h*\(.*\)\h*\n\h*\n?\z <ret> s \A|.\z <ret> 1<a-&>1<a-space><a-gt> ]
+    # deindent closing brace(s) when after cursor
+    try %[ execute-keys -draft <a-x> <a-k> ^\h*[})] <ret> gh / [})] <ret> m <a-S> 1<a-&> ]
+  >
+~
+
+define-command -hidden kotlin-indent-on-opening-curly-brace %[
+  # align indent with opening paren when { is entered on a new line after the closing paren
+  try %[ execute-keys -draft -itersel h<a-F>)M <a-k> \A\(.*\)\h*\n\h*\{\z <ret> s \A|.\z <ret> 1<a-&> ]
+]
+
+define-command -hidden kotlin-indent-on-closing-curly-brace %[
+  # align to opening curly brace when alone on a line
+  try %[ execute-keys -itersel -draft <a-h><a-k>^\h+\}$<ret>hms\A|.\z<ret>1<a-&> ]
+]
+
+# Exceptions, Errors, and Types -------------------------------------------------------------------- #
+# ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
+# macro: 93le<a-;>i<ret><esc><esc>
+evaluate-commands %sh{
+  kotlin_types='Annotation Any Boolean BooleanArray Byte ByteArray Char Character CharArray
+    CharSequence Class ClassLoader Cloneable Comparable Compiler DeprecationLevel Double
+    DoubleArray Enum Float FloatArray Function Int IntArray Integer Lazy LazyThreadSafetyMode
+    Long LongArray Math Nothing Number Object Package Pair Process Runnable Runtime
+    SecurityManager Short ShortArray StackTraceElement StrictMath String StringBuffer System
+    Thread ThreadGroup ThreadLocal Triple Unit Void'
+
+  # ------------------------------------------------------------------------------------------------ #
+
+  kotlin_kdocs='author constructor exception param property receiver return sample see since suppress throws'
+
+  # ------------------------------------------------------------------------------------------------ #
+
+  kotlin_errors_exceptions='CharacterCodingException Error AssertionError NotImplementedError
+    OutOfMemoryErrorIllegalCallableAccessException IllegalPropertyDelegateAccessException
+    NoSuchPropertyException RuntimeException Throwable'
+
+  # ------------------------------------------------------------------------------------------------ #
+
+  join() { sep=$2; eval set -- $1; IFS="$sep"; echo "$*"; }
+
+  # ------------------------------------------------------------------------------------------------ #
+
+  printf %s\\n "declare-option str-list kotlin_static_words $(join "${kotlin_types} ${kotlin_kdocs} ${kotlin_errors_exceptions}" ' ')"
+
+  # ------------------------------------------------------------------------------------------------ #
+
+  printf %s\\n "add-highlighter shared/kotlin/code/kotlin_errors_exceptions regex \b($(join "${kotlin_errors_exceptions}" '|'))\b 0:type"
+}
+§
+# ------------------------------------------------------------------------------------------------- #