diff --git a/src/plugins/documenter.jl b/src/plugins/documenter.jl
index 21d9bee..97ae7dc 100644
--- a/src/plugins/documenter.jl
+++ b/src/plugins/documenter.jl
@@ -32,8 +32,8 @@ function gen_plugin(p::Documenter, t::Template, pkg_name::AbstractString)
         "[]"
     end
 
-    kwargs_string = if "additional_kwargs" in fieldnames(typeof(p))
-        const set_kwargs = ["modules", "format", "pages", "repo", "sitename", "authors", "assets"]
+    kwargs_string = if :additional_kwargs in fieldnames(typeof(p))
+        set_kwargs = ["modules", "format", "pages", "repo", "sitename", "authors", "assets"]
 
         # We want something that looks like the following:
         #     key1="val1",
diff --git a/test/runtests.jl b/test/runtests.jl
index 8bcd9a8..13fa915 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -7,7 +7,7 @@ using Pkg
 import PkgTemplates: badges, version_floor, substitute, read_license, gen_file, gen_readme,
     gen_tests, gen_license, gen_require, gen_gitignore, gen_plugin, show_license, LICENSES,
     LICENSE_DIR, Plugin, GenericPlugin, CustomPlugin, Badge, format, interactive,
-    DEFAULTS_DIR
+    DEFAULTS_DIR, Documenter
 
 mktempdir() do temp_dir
     mkdir(joinpath(temp_dir, "dev"))
diff --git a/test/tests.jl b/test/tests.jl
index be1a9ae..aca2855 100644
--- a/test/tests.jl
+++ b/test/tests.jl
@@ -13,6 +13,11 @@ end
 struct Bar <: CustomPlugin end
 # A dummy Plugin subtype.
 struct Baz <: Plugin end
+# A Documenter with extra kwargs
+struct Bat <: Documenter
+    assets::Vector{AbstractString}
+    additional_kwargs::Vector{<:Pair}
+end
 
 # Various options to be passed into templates.
 const me = "christopher-dG"
@@ -397,4 +402,26 @@ end
     include(joinpath("plugins", "githubpages.jl"))
 end
 
+@testset "Documenter add kwargs" begin
+    t = Template(; user=me)
+    pkg_dir = joinpath(t.dir, test_pkg)
+    p = Bat(
+        [],
+        ["strict"=>true, "checkdocs"=>:none, "format"=>:markdown, "stringarg"=>"string"]
+    )
+    gen_plugin(p, t, test_pkg)
+    make = readchomp(joinpath(pkg_dir, "docs", "make.jl"))
+    @test occursin(
+        strip("""
+            strict=true,
+            checkdocs=:none,
+            stringarg="string",
+        """),
+        make,
+    )
+    @test !occursin("format=:markdown", make)
+    @test occursin("format=:html", make)
+    rm(pkg_dir; recursive=true)
+end
+
 rm(test_file)