diff --git a/IMPLS.yml b/IMPLS.yml
index 15749a158f..3a87be05a3 100644
--- a/IMPLS.yml
+++ b/IMPLS.yml
@@ -119,7 +119,7 @@ IMPL:
 # - {IMPL: swift3, NO_DOCKER: 1, OS: xcode8}
   - {IMPL: swift4}
 # - {IMPL: swift4, NO_DOCKER: 1, OS: xcode10}
-  - {IMPL: swift5}
-  - {IMPL: swift5, NO_DOCKER: 1, OS: macos}
+  - {IMPL: swift6}
+  - {IMPL: swift6, NO_DOCKER: 1, OS: macos}
 
   - {IMPL: vbs, NO_DOCKER: 1, OS: windows}
diff --git a/Makefile.impls b/Makefile.impls
index f126bc7612..dc596b0d8f 100644
--- a/Makefile.impls
+++ b/Makefile.impls
@@ -37,7 +37,7 @@ IMPLS = ada ada.2 awk bash basic bbc-basic c c.2 chuck clojure coffee common-lis
 	guile haskell haxe hy io janet java java-truffle js jq julia kotlin latex3 livescript logo lua make mal \
 	matlab miniMAL nasm nim objc objpascal ocaml perl perl6 php picolisp pike plpgsql \
 	plsql powershell prolog ps purs python2 python3 r racket rexx rpython ruby ruby.2 rust scala scheme skew sml \
-	swift swift3 swift4 swift5 tcl ts vala vb vbs vhdl vimscript wasm wren yorick xslt zig
+	swift swift3 swift4 swift6 tcl ts vala vb vbs vhdl vimscript wasm wren yorick xslt zig
 
 step5_EXCLUDES += bash        # never completes at 10,000
 step5_EXCLUDES += basic       # too slow, and limited to ints of 2^16
@@ -188,7 +188,7 @@ sml_STEP_TO_PROG =           impls/sml/$($(1))
 swift_STEP_TO_PROG =         impls/swift/$($(1))
 swift3_STEP_TO_PROG =        impls/swift3/$($(1))
 swift4_STEP_TO_PROG =        impls/swift4/$($(1))
-swift5_STEP_TO_PROG =        impls/swift5/$($(1))
+swift6_STEP_TO_PROG =        impls/swift6/$($(1))
 tcl_STEP_TO_PROG =           impls/tcl/$($(1)).tcl
 ts_STEP_TO_PROG =            impls/ts/$($(1)).js
 vala_STEP_TO_PROG =          impls/vala/$($(1))
diff --git a/README.md b/README.md
index 7f5bade334..fb12d573f7 100644
--- a/README.md
+++ b/README.md
@@ -127,7 +127,7 @@ FAQ](docs/FAQ.md) where I attempt to answer some common questions.
 | [Standard ML](#sml) | [Fabian Bergström](https://github.com/fabjan) |
 | [Swift 3](#swift-3) | [Joel Martin](https://github.com/kanaka)  |
 | [Swift 4](#swift-4) | [陆遥](https://github.com/LispLY)  |
-| [Swift 5](#swift-5) | [Oleg Montak](https://github.com/MontakOleg)  |
+| [Swift 6](#swift-6) | [Oleg Montak](https://github.com/MontakOleg)  |
 | [Tcl](#tcl-86) | [Dov Murik](https://github.com/dubek) |
 | [TypeScript](#typescript) | [Masahiro Wakame](https://github.com/vvakame) |
 | [Vala](#vala) | [Simon Tatham](https://github.com/sgtatham) |
@@ -1150,7 +1150,7 @@ The Swift 5 implementation of mal requires the Swift 5.0 compiler. It
 has been tested with Swift 5.1.1 release.
 
 ```
-cd impls/swift5
+cd impls/swift6
 swift run stepX_YYY
 ```
 
diff --git a/docs/graph/base_data.yaml b/docs/graph/base_data.yaml
index a516fce83d..53940f760e 100644
--- a/docs/graph/base_data.yaml
+++ b/docs/graph/base_data.yaml
@@ -81,7 +81,7 @@ languages:
   - [scheme        , Scheme (R7RS)    , Lisp   , Dynamic    , [chibi,kawa,gauche,chicken,sagittarius,cyclone,foment]]
   - [skew          , Skew             , OTHER  , Static     , []]
   - [sml           , "Standard ML"    , ML     , Static     , []]
-  - [swift5        , "Swift 5"        , C      , Static     , []]
+  - [swift6        , "Swift 6"        , C      , Static     , []]
   - [tcl           , Tcl              , OTHER  , Dynamic    , []]
   - [ts            , TypeScript       , C      , Static     , []]
   - [vala          , Vala             , C      , Static     , []]
diff --git a/docs/graph/so-tags.csv b/docs/graph/so-tags.csv
index fb2f22b228..0a28fe1f9a 100644
--- a/docs/graph/so-tags.csv
+++ b/docs/graph/so-tags.csv
@@ -2327,7 +2327,7 @@ Rate,TagName
 "3129","userform"
 "3128","multi-tenant"
 "3125","expandablelistview"
-"3123","swift5"
+"3123","swift6"
 "3122","sql-delete"
 "3121","serverless-framework"
 "3117","core-location"
diff --git a/impls/swift5/.gitignore b/impls/swift6/.gitignore
similarity index 100%
rename from impls/swift5/.gitignore
rename to impls/swift6/.gitignore
diff --git a/impls/swift5/Dockerfile b/impls/swift6/Dockerfile
similarity index 100%
rename from impls/swift5/Dockerfile
rename to impls/swift6/Dockerfile
diff --git a/impls/swift5/Makefile b/impls/swift6/Makefile
similarity index 100%
rename from impls/swift5/Makefile
rename to impls/swift6/Makefile
diff --git a/impls/swift5/Package.swift b/impls/swift6/Package.swift
similarity index 100%
rename from impls/swift5/Package.swift
rename to impls/swift6/Package.swift
diff --git a/impls/swift5/Sources/core/Core.swift b/impls/swift6/Sources/core/Core.swift
similarity index 100%
rename from impls/swift5/Sources/core/Core.swift
rename to impls/swift6/Sources/core/Core.swift
diff --git a/impls/swift5/Sources/core/Env.swift b/impls/swift6/Sources/core/Env.swift
similarity index 100%
rename from impls/swift5/Sources/core/Env.swift
rename to impls/swift6/Sources/core/Env.swift
diff --git a/impls/swift5/Sources/core/Errors.swift b/impls/swift6/Sources/core/Errors.swift
similarity index 100%
rename from impls/swift5/Sources/core/Errors.swift
rename to impls/swift6/Sources/core/Errors.swift
diff --git a/impls/swift5/Sources/core/Parser.swift b/impls/swift6/Sources/core/Parser.swift
similarity index 100%
rename from impls/swift5/Sources/core/Parser.swift
rename to impls/swift6/Sources/core/Parser.swift
diff --git a/impls/swift5/Sources/core/Printer.swift b/impls/swift6/Sources/core/Printer.swift
similarity index 100%
rename from impls/swift5/Sources/core/Printer.swift
rename to impls/swift6/Sources/core/Printer.swift
diff --git a/impls/swift5/Sources/core/Reader.swift b/impls/swift6/Sources/core/Reader.swift
similarity index 100%
rename from impls/swift5/Sources/core/Reader.swift
rename to impls/swift6/Sources/core/Reader.swift
diff --git a/impls/swift5/Sources/core/Types.swift b/impls/swift6/Sources/core/Types.swift
similarity index 100%
rename from impls/swift5/Sources/core/Types.swift
rename to impls/swift6/Sources/core/Types.swift
diff --git a/impls/swift5/Sources/core/Utils.swift b/impls/swift6/Sources/core/Utils.swift
similarity index 100%
rename from impls/swift5/Sources/core/Utils.swift
rename to impls/swift6/Sources/core/Utils.swift
diff --git a/impls/swift5/Sources/step0_repl/main.swift b/impls/swift6/Sources/step0_repl/main.swift
similarity index 100%
rename from impls/swift5/Sources/step0_repl/main.swift
rename to impls/swift6/Sources/step0_repl/main.swift
diff --git a/impls/swift5/Sources/step1_read_print/main.swift b/impls/swift6/Sources/step1_read_print/main.swift
similarity index 100%
rename from impls/swift5/Sources/step1_read_print/main.swift
rename to impls/swift6/Sources/step1_read_print/main.swift
diff --git a/impls/swift5/Sources/step2_eval/main.swift b/impls/swift6/Sources/step2_eval/main.swift
similarity index 100%
rename from impls/swift5/Sources/step2_eval/main.swift
rename to impls/swift6/Sources/step2_eval/main.swift
diff --git a/impls/swift5/Sources/step3_env/main.swift b/impls/swift6/Sources/step3_env/main.swift
similarity index 100%
rename from impls/swift5/Sources/step3_env/main.swift
rename to impls/swift6/Sources/step3_env/main.swift
diff --git a/impls/swift5/Sources/step4_if_fn_do/main.swift b/impls/swift6/Sources/step4_if_fn_do/main.swift
similarity index 100%
rename from impls/swift5/Sources/step4_if_fn_do/main.swift
rename to impls/swift6/Sources/step4_if_fn_do/main.swift
diff --git a/impls/swift5/Sources/step5_tco/main.swift b/impls/swift6/Sources/step5_tco/main.swift
similarity index 100%
rename from impls/swift5/Sources/step5_tco/main.swift
rename to impls/swift6/Sources/step5_tco/main.swift
diff --git a/impls/swift5/Sources/step6_file/main.swift b/impls/swift6/Sources/step6_file/main.swift
similarity index 100%
rename from impls/swift5/Sources/step6_file/main.swift
rename to impls/swift6/Sources/step6_file/main.swift
diff --git a/impls/swift5/Sources/step7_quote/main.swift b/impls/swift6/Sources/step7_quote/main.swift
similarity index 100%
rename from impls/swift5/Sources/step7_quote/main.swift
rename to impls/swift6/Sources/step7_quote/main.swift
diff --git a/impls/swift5/Sources/step8_macros/main.swift b/impls/swift6/Sources/step8_macros/main.swift
similarity index 100%
rename from impls/swift5/Sources/step8_macros/main.swift
rename to impls/swift6/Sources/step8_macros/main.swift
diff --git a/impls/swift5/Sources/step9_try/main.swift b/impls/swift6/Sources/step9_try/main.swift
similarity index 100%
rename from impls/swift5/Sources/step9_try/main.swift
rename to impls/swift6/Sources/step9_try/main.swift
diff --git a/impls/swift5/Sources/stepA_mal/main.swift b/impls/swift6/Sources/stepA_mal/main.swift
similarity index 99%
rename from impls/swift5/Sources/stepA_mal/main.swift
rename to impls/swift6/Sources/stepA_mal/main.swift
index 0afd903525..d10767842a 100644
--- a/impls/swift5/Sources/stepA_mal/main.swift
+++ b/impls/swift6/Sources/stepA_mal/main.swift
@@ -216,7 +216,7 @@ replEnv.set(forKey: "eval", val: .function(Func { args in
     return try eval(expr, env: replEnv)
 }))
 replEnv.set(forKey: "*ARGV*", val: .list(CommandLine.arguments.dropFirst(2).map(Expr.string)))
-replEnv.set(forKey: "*host-language*", val: .string("swift5"))
+replEnv.set(forKey: "*host-language*", val: .string("swift6"))
 
 rep("(def! not (fn* (a) (if a false true)))", env: replEnv)
 rep(#"(def! load-file (fn* (f) (eval (read-string (str "(do " (slurp f) "\nnil)")))))"#, env: replEnv)
diff --git a/impls/swift5/run b/impls/swift6/run
similarity index 100%
rename from impls/swift5/run
rename to impls/swift6/run