diff --git a/README.md b/README.md
index 661227f..cef0d8b 100644
--- a/README.md
+++ b/README.md
@@ -18,8 +18,9 @@
 - [ ] [golines](https://pkg.go.dev/github.com/segmentio/golines)
 - [ ] [google-java-format](https://github.com/google/google-java-format)
 - [ ] [isort](https://github.com/PyCQA/isort)
-- [ ] [mixformat](https://github.com/elixir-lang/elixir/)
 - [x] [latexindent](https://github.com/cmhughes/latexindent.pl)
+- [ ] [mixformat](https://github.com/elixir-lang/elixir/)
+- [ ] [nixfmt](https://github.com/serokell/nixfmt)
 - [ ] [pg_format](https://github.com/darold/pgFormatter)
 - [x] [prettier](https://github.com/prettier/prettier)
 - [ ] [rubocop](https://github.com/rubocop/rubocop)
diff --git a/lua/guard-collection/formatter.lua b/lua/guard-collection/formatter.lua
index 84baf57..9ec3400 100644
--- a/lua/guard-collection/formatter.lua
+++ b/lua/guard-collection/formatter.lua
@@ -81,6 +81,11 @@ M.mixformat = {
   fname = true,
 }
 
+M.nixfmt = {
+  cmd = 'nixfmt',
+  stdin = true,
+}
+
 M.pg_format = {
   cmd = 'pg_format',
   stdin = true,
diff --git a/test/setup.sh b/test/setup.sh
index afc3c74..6a3c714 100644
--- a/test/setup.sh
+++ b/test/setup.sh
@@ -35,6 +35,10 @@ chmod +x $bin/stylua
 wget -q "$gh/cmhughes/latexindent.pl/releases/download/V3.22.2/latexindent-linux"
 chmod +x latexindent-linux
 mv latexindent-linux $bin/latexindent
+# nixfmt
+wget -q "$gh/serokell/nixfmt/releases/download/v0.5.0/nixfmt"
+chmod +x nixfmt
+mv nixfmt $bin/nixfmt
 
 # test setup
 luarocks install vusted