diff --git a/include-code-files/Makefile b/include-code-files/Makefile
new file mode 100644
index 00000000..6b169e09
--- /dev/null
+++ b/include-code-files/Makefile
@@ -0,0 +1,10 @@
+DIFF ?= diff --strip-trailing-cr -u
+
+test: sample.md include-code-files.lua
+	@pandoc --lua-filter=include-code-files.lua --to=native $< \
+	    | $(DIFF) expected.native -
+
+expected.native: sample.md include-code-files.lua
+	pandoc --lua-filter=include-code-files.lua --output $@ $<
+
+.PHONY: test
diff --git a/include-code-files/README.md b/include-code-files/README.md
new file mode 100644
index 00000000..e52ef279
--- /dev/null
+++ b/include-code-files/README.md
@@ -0,0 +1,54 @@
+# include-code-files
+
+Filter to include code from source files.
+
+The filter is largely inspired by [pandoc-include-code](https://github.com/owickstrom/pandoc-include-code).
+
+## Usage
+
+The filter recognizes code blocks with the `include` attribute present. It
+swaps the content of the code block with contents from a file.
+
+### Including Files
+
+The simplest way to use this filter is to include an entire file:
+
+    ```{include="hello.c"}
+    ```
+
+You can still use other attributes, and classes, to control the code blocks:
+
+    ```{.c include="hello.c" numberLines}
+    ```
+
+### Ranges
+
+If you want to include a specific range of lines, use `startLine` and `endLine`:
+
+    ```{include="hello.c" startLine=35 endLine=80}
+    ```
+
+### Dedent
+
+Using the `dedent` attribute, you can have whitespaces removed on each line,
+where possible (non-whitespace character will not be removed even if they occur
+in the dedent area).
+
+    ```{include="hello.c" dedent=4}
+    ```
+
+### Line Numbers
+
+If you include the `numberLines` class in your code block, and use `include`,
+the `startFrom` attribute will be added with respect to the included code's
+location in the source file.
+
+    ```{include="hello.c" startLine=35 endLine=80 .numberLines}
+    ```
+
+## Example
+
+An HTML can be produced with this command:
+
+    pandoc --lua-filter=include-code-files.lua sample.md --output result.html
+
diff --git a/include-code-files/expected.native b/include-code-files/expected.native
new file mode 100644
index 00000000..18e4aca1
--- /dev/null
+++ b/include-code-files/expected.native
@@ -0,0 +1,8 @@
+[Header 1 ("inclusion",[],[]) [Str "Inclusion"]
+,CodeBlock ("",["lua","numberLines"],[]) "--- include-code-files.lua \8211 filter to include code from source files\n---\n--- Copyright: \169 2020 Bruno BEAUFILS\n--- License:   MIT \8211 see LICENSE file for details\n\n--- Dedent a line\nlocal function dedent (line, n)\n  return line:sub(1,n):gsub(\" \",\"\") .. line:sub(n+1)\nend\n\n--- Filter function for code blocks\nlocal function transclude (cb)\n  if cb.attributes.include then\n    local content = \"\"\n    local fh = io.open(cb.attributes.include)\n    if not fh then\n      io.stderr:write(\"Cannot open file \" .. cb.attributes.include .. \" | Skipping includes\\n\")\n    else\n      local number = 1\n      local start = 1\n      if cb.attributes.startLine then\n        cb.attributes.startFrom = cb.attributes.startLine\n        start = tonumber(cb.attributes.startLine)\n      end\n      for line in fh:lines (\"L\")\n      do\n        if cb.attributes.dedent then\n          line = dedent(line, cb.attributes.dedent)\n        end\n        if number >= start then\n          if not cb.attributes.endLine or number <= tonumber(cb.attributes.endLine) then\n            content = content .. line\n          end\n        end\n        number = number + 1\n      end \n      fh:close()\n    end     \n    -- remove key-value pair for used keys\n    cb.attributes.include = nil\n    cb.attributes.startLine = nil\n    cb.attributes.endLine = nil\n    cb.attributes.dedent = nil\n    -- return final code block\n    return pandoc.CodeBlock(content, cb.attr)\n  end\nend\n\nreturn {\n  { CodeBlock = transclude }\n}\n"
+,Header 1 ("ranges",[],[]) [Str "Ranges"]
+,CodeBlock ("",["lua","numberLines"],[("startFrom","7")]) "local function dedent (line, n)\n  return line:sub(1,n):gsub(\" \",\"\") .. line:sub(n+1)\nend\n"
+,Header 1 ("detent",[],[]) [Str "Detent"]
+,Para [Code ("",[],[]) "detent",Space,Str "removes",Space,Str "specified",Space,Str "number",Space,Str "of",Space,Str "whitespaces",Space,Str "(and",Space,Str "only",SoftBreak,Str "whitespaces)",Space,Str "from",Space,Str "beginning",Space,Str "of",Space,Str "each",Space,Str "line"]
+,CodeBlock ("",["lua","bash","numberLines"],[("startFrom","8")]) "return line:sub(1,n):gsub(\" \",\"\") .. line:sub(n+1)\n"
+,CodeBlock ("",["lua","numberLines"],[("startFrom","50")]) "{CodeBlock = transclude }\n"]
diff --git a/include-code-files/include-code-files.lua b/include-code-files/include-code-files.lua
new file mode 100644
index 00000000..df744bf7
--- /dev/null
+++ b/include-code-files/include-code-files.lua
@@ -0,0 +1,51 @@
+--- include-code-files.lua – filter to include code from source files
+---
+--- Copyright: © 2020 Bruno BEAUFILS
+--- License:   MIT – see LICENSE file for details
+
+--- Dedent a line
+local function dedent (line, n)
+  return line:sub(1,n):gsub(" ","") .. line:sub(n+1)
+end
+
+--- Filter function for code blocks
+local function transclude (cb)
+  if cb.attributes.include then
+    local content = ""
+    local fh = io.open(cb.attributes.include)
+    if not fh then
+      io.stderr:write("Cannot open file " .. cb.attributes.include .. " | Skipping includes\n")
+    else
+      local number = 1
+      local start = 1
+      if cb.attributes.startLine then
+        cb.attributes.startFrom = cb.attributes.startLine
+        start = tonumber(cb.attributes.startLine)
+      end
+      for line in fh:lines ("L")
+      do
+        if cb.attributes.dedent then
+          line = dedent(line, cb.attributes.dedent)
+        end
+        if number >= start then
+          if not cb.attributes.endLine or number <= tonumber(cb.attributes.endLine) then
+            content = content .. line
+          end
+        end
+        number = number + 1
+      end 
+      fh:close()
+    end     
+    -- remove key-value pair for used keys
+    cb.attributes.include = nil
+    cb.attributes.startLine = nil
+    cb.attributes.endLine = nil
+    cb.attributes.dedent = nil
+    -- return final code block
+    return pandoc.CodeBlock(content, cb.attr)
+  end
+end
+
+return {
+  { CodeBlock = transclude }
+}
diff --git a/include-code-files/sample.md b/include-code-files/sample.md
new file mode 100644
index 00000000..a929adde
--- /dev/null
+++ b/include-code-files/sample.md
@@ -0,0 +1,26 @@
+---
+author: me
+title: Including Hello World
+---
+
+# Inclusion
+
+``` {include="include-code-files.lua" .lua .numberLines}
+```
+
+# Ranges
+
+``` {include="include-code-files.lua" .lua startLine=7 endLine=9 .numberLines}
+```
+
+# Detent
+
+`detent` removes specified number of whitespaces (and only
+whitespaces) from beginning of each line
+
+``` {include="include-code-files.lua" .lua startLine=8 endLine=8 dedent=4 .bash .numberLines}
+```
+
+``` {include="include-code-files.lua" .lua startLine=50 endLine=50 dedent=5 .numberLines}
+```
+
diff --git a/include-files/Makefile b/include-files/Makefile
index c5f5279e..d667c933 100644
--- a/include-files/Makefile
+++ b/include-files/Makefile
@@ -1,15 +1,15 @@
 DIFF ?= diff --strip-trailing-cr -u
 
-test: sample.md file-a.md file-b.md file-c.md include-files.lua
+test: sample.md file-a.md file-b.md file-c.md shell1 shell2 include-files.lua
 	@pandoc --lua-filter=include-files.lua --to=native $< \
 	    | $(DIFF) expected.native -
 	@pandoc --lua-filter=include-files.lua -M include-auto --to=native $< \
 	    | $(DIFF) expected-auto.native -
 
-expected.native: sample.md file-a.md file-b.md file-c.md include-files.lua
+expected.native: sample.md file-a.md file-b.md file-c.md shell1 shell2 include-files.lua
 	pandoc --lua-filter=include-files.lua --output $@ $<
 
-expected-auto.native: sample.md file-a.md file-b.md file-c.md include-files.lua
-	pandoc --lua-filter=include-files.lua --output $@ $<
+expected-auto.native: sample.md file-a.md file-b.md file-c.md shell1 shell2 include-files.lua
+	pandoc --lua-filter=include-files.lua -M include-auto --output $@ $<
 
 .PHONY: test
diff --git a/include-files/README.md b/include-files/README.md
index a99402a2..f1596016 100644
--- a/include-files/README.md
+++ b/include-files/README.md
@@ -11,6 +11,9 @@ document.
 
 Metadata from included files is discarded.
 
+Add class `source` to include files as normal code blocks taken from
+files instead of text in same format as the input.
+
 ### Shifting Headings
 
 The default is to include the subdocuments unchanged, but it can
@@ -59,6 +62,9 @@ will want to include files written in a different format. An
 alternative format can be specified via the `format` attribute.
 Only plain-text formats are accepted.
 
+In order to include source code block from files use additional class
+`source` instead of trying the language as `format`.
+
 ### Recursive transclusion
 
 Included files can in turn include other files. Note that all
@@ -101,6 +107,13 @@ some additional information in the main file `main.md`:
     appendix/questionaire.md
     ```
 
+    ## Source code
+
+    ``` {.include .source .lua}
+    // code of this nice filter
+    include-files.lua
+    ```
+
 An HTML can be produced with this command:
 
     pandoc --lua-filter=include-files.lua main.md --output result.html
diff --git a/include-files/expected-auto.native b/include-files/expected-auto.native
index 22be9279..dd398cb0 100644
--- a/include-files/expected-auto.native
+++ b/include-files/expected-auto.native
@@ -16,6 +16,8 @@
 ,Para [Str "This",Space,Str "is",Space,Code ("",[],[]) "file-a.md",Str "."]
 ,Header 3 ("title-of-file-a",[],[]) [Str "Title",Space,Str "of",Space,Str "file-a"]
 ,Para [Str "This",Space,Str "is",Space,Code ("",[],[]) "file-a.md",Str "."]
+,Header 1 ("source-code",[],[]) [Str "Source",Space,Str "code"]
+,CodeBlock ("",["include","source","bash"],[]) "#!/bin/bash\n\necho \"Hello World !\"\n\n#!/bin/bash\nfor i in \"Hello \" \"World \" \"!\\n\" \ndo\n\tprintf \"$i\"\ndone\n\n"
 ,Header 1 ("appendix",[],[]) [Str "Appendix"]
 ,Para [Str "More",Space,Str "info",Space,Str "goes",Space,Str "here."]
 ,Header 2 ("questionaire",[],[]) [Str "Questionaire"]
diff --git a/include-files/expected.native b/include-files/expected.native
index d50caa48..f8c3fcd5 100644
--- a/include-files/expected.native
+++ b/include-files/expected.native
@@ -16,6 +16,8 @@
 ,Para [Str "This",Space,Str "is",Space,Code ("",[],[]) "file-a.md",Str "."]
 ,Header 2 ("title-of-file-a",[],[]) [Str "Title",Space,Str "of",Space,Str "file-a"]
 ,Para [Str "This",Space,Str "is",Space,Code ("",[],[]) "file-a.md",Str "."]
+,Header 1 ("source-code",[],[]) [Str "Source",Space,Str "code"]
+,CodeBlock ("",["include","source","bash"],[]) "#!/bin/bash\n\necho \"Hello World !\"\n\n#!/bin/bash\nfor i in \"Hello \" \"World \" \"!\\n\" \ndo\n\tprintf \"$i\"\ndone\n\n"
 ,Header 1 ("appendix",[],[]) [Str "Appendix"]
 ,Para [Str "More",Space,Str "info",Space,Str "goes",Space,Str "here."]
 ,Header 2 ("questionaire",[],[]) [Str "Questionaire"]
diff --git a/include-files/include-files.lua b/include-files/include-files.lua
index f685ec00..e060843d 100644
--- a/include-files/include-files.lua
+++ b/include-files/include-files.lua
@@ -1,4 +1,4 @@
---- include-files.lua – filter to include Markdown files
+--- include-files.lua – filter to include files
 ---
 --- Copyright: © 2019–2020 Albert Krewinkel
 --- License:   MIT – see LICENSE file for details
@@ -43,6 +43,22 @@ function transclude (cb)
   if not cb.classes:includes 'include' then
     return
   end
+  -- process files as source code blocks
+  if cb.classes:includes 'source' then
+     local contents = ""
+     for line in cb.text:gmatch('[^\n]+') do
+       if line:sub(1,2) ~= '//' then
+         local fh = io.open(line)
+         if not fh then
+           io.stderr:write("Cannot open file " .. line .. " | Skipping includes\n")
+         else
+           contents = contents .. fh:read('*a')
+           fh:close()
+         end
+      end
+    end
+    return pandoc.CodeBlock(contents, cb.attr)
+  end
 
   -- Markdown is used if this is nil.
   local format = cb.attributes['format']
diff --git a/include-files/sample.md b/include-files/sample.md
index b0352fb8..191d1936 100644
--- a/include-files/sample.md
+++ b/include-files/sample.md
@@ -28,6 +28,14 @@ file-d.org
 file-f.md
 ```
 
+# Source code
+
+``` {.include .source .bash}
+// this will include simple bash files
+shell1
+shell2
+```
+
 # Appendix
 
 More info goes here.
diff --git a/include-files/shell1 b/include-files/shell1
new file mode 100644
index 00000000..4d0a6dc1
--- /dev/null
+++ b/include-files/shell1
@@ -0,0 +1,4 @@
+#!/bin/bash
+
+echo "Hello World !"
+
diff --git a/include-files/shell2 b/include-files/shell2
new file mode 100644
index 00000000..a635b20f
--- /dev/null
+++ b/include-files/shell2
@@ -0,0 +1,6 @@
+#!/bin/bash
+for i in "Hello " "World " "!\n" 
+do
+	printf "$i"
+done
+