diff --git a/l3build-variables.lua b/l3build-variables.lua
index 5d4e3265..4dbe0663 100644
--- a/l3build-variables.lua
+++ b/l3build-variables.lua
@@ -86,7 +86,7 @@ installfiles       = installfiles       or {"*.sty","*.cls"}
 makeindexfiles     = makeindexfiles     or {"*.ist"}
 scriptfiles        = scriptfiles        or { }
 scriptmanfiles     = scriptmanfiles     or { }
-sourcefiles        = sourcefiles        or {"*.dtx", "*.ins"}
+sourcefiles        = sourcefiles        or {"*.dtx", "*.ins", "*-????-??-??.sty"}
 tagfiles           = tagfiles           or {"*.dtx"}
 textfiles          = textfiles          or {"*.md", "*.txt"}
 typesetdemofiles   = typesetdemofiles   or { }
diff --git a/l3build.dtx b/l3build.dtx
index a87e0724..74460c16 100644
--- a/l3build.dtx
+++ b/l3build.dtx
@@ -89,7 +89,7 @@
 \luavarset{makeindexfiles}    {\{"*.ist"\}}{MakeIndex files to be included in a TDS-style zip}
 \luavarset{scriptfiles}       {\{ \}}{Files to install to the \texttt{scripts} area of the \texttt{texmf} tree}
 \luavarset{scriptmanfiles}    {\{ \}}{Files to install to the \texttt{doc/man} area of the \texttt{texmf} tree}
-\luavarset{sourcefiles}       {\{"*.dtx", "*.ins"\}}{Files to copy for unpacking}
+\luavarset{sourcefiles}       {\{"*.dtx", "*.ins", "*-????-??-??.sty"\}}{Files to copy for unpacking}
 \luavarset{tagfiles}          {\{"*.dtx"\}}{Files for automatic tagging}
 \luavarset{textfiles}         {\{"*.md", "*.txt"\}}{Plain text files to send to CTAN as-is}
 \luavarset{typesetdemofiles}  {\{\}}{Files to typeset before the documentation for inclusion in main documentation files}