diff --git a/src/bin/dotify b/src/bin/dotify
index 7ec8107..f992bd2 100755
--- a/src/bin/dotify
+++ b/src/bin/dotify
@@ -37,8 +37,11 @@ source "../lib/trim.sh"
 # Internal functions
 #
 
-source "../lib/parse-dotfile-options.sh"
-source "../lib/internals.sh"
+source "../lib/internals/compile-dotfile.sh"
+source "../lib/internals/create-symlink.sh"
+source "../lib/internals/locate-dotfile.sh"
+source "../lib/internals/locate-target.sh"
+source "../lib/internals/parse-dotfile-options.sh"
 
 #
 # Command functions
diff --git a/src/lib/internals.sh b/src/lib/internals.sh
deleted file mode 100644
index dba2ce8..0000000
--- a/src/lib/internals.sh
+++ /dev/null
@@ -1,93 +0,0 @@
-locate-dotfile() {
-  if [ -n "$DOTFILE" ]; then
-    if [ ! -f "$DOTFILE" ]; then
-      echo "ERROR: \"$DOTFILE\" does not exist." >&2
-      return 1
-    fi
-  elif [ -f "$(pwd)/Dotfile" ]; then
-    DOTFILE="$(pwd)/Dotfile"
-  else
-    echo "ERROR: \"$(pwd)\" does not have a Dotfile." >&2
-    return 1
-  fi
-}
-
-locate-target() {
-  if [ -n "$TARGET" ]; then
-    if [ ! -d "$TARGET" ]; then
-      echo "ERROR: Target \"$TARGET\" is not a directory." >&2
-      return 1
-    fi
-  elif [ -n "$HOME" ] && [ -d "$HOME" ]; then
-    TARGET="$HOME"
-  elif [ -d ~ ]; then
-    TARGET=~
-  else
-    echo "ERROR: Your \$HOME folder could not be found." >&2
-    return 1
-  fi
-}
-
-create-symlink() {
-  local source="$1"
-  local target="$2"
-}
-
-execute-dotfile() {
-  parse-dotfile-options
-  local root_dir="$(dirname "$DOTFILE")"
-
-  local cwd="$(pwd)"
-  cd "$root_dir"
-
-  create-symlink "$root_dir" "$TARGET/$OPT_ROOT_LINK"
-  if [ -n "$?" ]; then return 1; fi
-
-  while read line; do
-    parse-dotfile-line "$line"
-    if [ -n "$?" ]; then return 1; fi
-  done < "$DOTFILE"
-
-  cd "$cwd"
-}
-
-parse-dotfile-line() {
-  local line="$(trim "$1")"
-  local dotfile="$DOTFILE"
-  if [ -n "$2" ]; then dotfile="$2"; fi
-
-  # Ignore comment lines starting with "#".
-  if [[ "$line" == "#"* ]]; then return 0; fi
-
-  # Ignore Dotfile options.
-  if [[ "$line" == "root_link "* ]]; then return 0; fi
-  if [[ "$line" == "default_action "* ]]; then return 0; fi
-
-  # Handle include command.
-  if [[ "$line" == "include "* ]]; then
-    include-dotfile "$(trim "${line/#include /}")"
-    return "$?"
-  fi
-
-  echo "$line"
-}
-
-include-dotfile() {
-  local dotfile="$1"
-  local root_dir="$(dirname "$dotfile")"
-
-  local cwd="$(pwd)"
-  cd "$root_dir"
-
-  if [ ! -f "$dotfile" ]; then
-    echo "ERROR: Can not include \"$dotfile\", it does not exist." >&2
-    return 1
-  fi
-
-  while read line; do
-    parse-dotfile-line "$line" "$dotfile"
-    if [ -n "$?" ]; then return 1; fi
-  done < "$dotfile"
-
-  cd "$cwd"
-}
diff --git a/src/lib/internals/compile-dotfile.sh b/src/lib/internals/compile-dotfile.sh
new file mode 100644
index 0000000..7cb1c6d
--- /dev/null
+++ b/src/lib/internals/compile-dotfile.sh
@@ -0,0 +1,31 @@
+compile-dotfile() {
+  local dotfile="$1"
+  if [ -z "$dotfile" ]; then dotfile="$DOTFILE"; fi
+
+  local output=""
+  local line=""
+  while IFS= read line; do
+    # Ignore comments and blank lines.
+    if [[ "$line" =~ ^(\ *\#.*|\ *)$ ]]; then
+      continue
+
+    # Parse "<action>: <source> -> <target>" lines.
+    elif [[ "$line" =~ ^(\ +)?([a-zA-Z0-9_-]+):\ (.+)\ +-[\>]\ +(.+)$ ]]; then
+      output="${output}${BASH_REMATCH[1]}dotify-action ${BASH_REMATCH[2]} "
+      output="${output}$(trim "${BASH_REMATCH[3]}") "
+      output="${output}$(trim "${BASH_REMATCH[4]}")\n"
+
+    # Parse "<source> -> <target>" lines.
+    elif [[ "$line" =~ ^(\ +)?(.+)\ -[\>]\ (.+)$ ]]; then
+      output="${output}${BASH_REMATCH[1]}dotify-action default "
+      output="${output}$(trim "${BASH_REMATCH[2]}") "
+      output="${output}$(trim "${BASH_REMATCH[3]}")\n"
+
+    # Append line without modifications.
+    else
+      output="${output}${line}\n"
+    fi
+  done < "$dotfile"
+
+  echo -e "$output"
+}
diff --git a/src/lib/internals/create-symlink.sh b/src/lib/internals/create-symlink.sh
new file mode 100644
index 0000000..d16a54a
--- /dev/null
+++ b/src/lib/internals/create-symlink.sh
@@ -0,0 +1,18 @@
+create-symlink() {
+  local source="$1"
+  local target="$2"
+
+  if [ ! -e "$target" ] && [ ! -h "$target" ]; then
+    ln -s "$source" "$target"
+    return 0
+  elif [ -h "$target" ]; then
+    if [ "$(readlink "$target")" != "$source" ]; then
+      echo "ERROR: \"$target\" exists, is a symlink to:" \
+        "$(readlink "$target")" >&2
+      return 1
+    fi
+  else
+    echo "ERROR: \"$target\" exists" >&2
+    return 1
+  fi
+}
diff --git a/src/lib/internals/locate-dotfile.sh b/src/lib/internals/locate-dotfile.sh
new file mode 100644
index 0000000..b4713b4
--- /dev/null
+++ b/src/lib/internals/locate-dotfile.sh
@@ -0,0 +1,13 @@
+locate-dotfile() {
+  if [ -n "$DOTFILE" ]; then
+    if [ ! -f "$DOTFILE" ]; then
+      echo "ERROR: \"$DOTFILE\" does not exist." >&2
+      return 1
+    fi
+  elif [ -f "$(pwd)/Dotfile" ]; then
+    DOTFILE="$(pwd)/Dotfile"
+  else
+    echo "ERROR: \"$(pwd)\" does not have a Dotfile." >&2
+    return 1
+  fi
+}
diff --git a/src/lib/internals/locate-target.sh b/src/lib/internals/locate-target.sh
new file mode 100644
index 0000000..f4a6bd0
--- /dev/null
+++ b/src/lib/internals/locate-target.sh
@@ -0,0 +1,15 @@
+locate-target() {
+  if [ -n "$TARGET" ]; then
+    if [ ! -d "$TARGET" ]; then
+      echo "ERROR: Target \"$TARGET\" is not a directory." >&2
+      return 1
+    fi
+  elif [ -n "$HOME" ] && [ -d "$HOME" ]; then
+    TARGET="$HOME"
+  elif [ -d ~ ]; then
+    TARGET=~
+  else
+    echo "ERROR: Your \$HOME folder could not be found." >&2
+    return 1
+  fi
+}
diff --git a/src/lib/parse-dotfile-options.sh b/src/lib/internals/parse-dotfile-options.sh
similarity index 80%
rename from src/lib/parse-dotfile-options.sh
rename to src/lib/internals/parse-dotfile-options.sh
index ba54349..850e727 100644
--- a/src/lib/parse-dotfile-options.sh
+++ b/src/lib/internals/parse-dotfile-options.sh
@@ -1,7 +1,17 @@
 # Parse Dotfile options and set relevant global variables.
 parse-dotfile-options() {
-  OPT_ROOT_LINK="$(parse-dotfile-root_link-option)"
-  OPT_DEFAULT_ACTION="$(parse-dotfile-default_action-option)"
+  DOTIFY_OPT_ROOT_LINK="$(parse-dotfile-root_link-option)"
+  DOTIFY_OPT_DEFAULT_ACTION="$(parse-dotfile-default_action-option)"
+}
+
+# Parse root_link option.
+parse-dotfile-root_link-option() {
+  echo "$(parse-dotfile-option "root_link" ".dotfiles" "$1")"
+}
+
+# Parse default_action option.
+parse-dotfile-default_action-option() {
+  echo "$(parse-dotfile-option "default_action" "link" "$1")"
 }
 
 # Extract a specific option from Dotfile.
@@ -17,6 +27,7 @@ parse-dotfile-option() {
   local dotfile="$3"
   if [ -z "$dotfile" ]; then dotfile="$DOTFILE"; fi
 
+  local line=""
   while read line; do
     if [[ "$line" == "$name "* ]]; then
       value="$(trim "${line/#$name }")"
@@ -26,11 +37,3 @@ parse-dotfile-option() {
 
   echo "$value"
 }
-
-parse-dotfile-root_link-option() {
-  echo "$(parse-dotfile-option "root_link" ".dotfiles" "$1")"
-}
-
-parse-dotfile-default_action-option() {
-  echo "$(parse-dotfile-option "default_action" "link" "$1")"
-}
diff --git a/test/lib/internals/create-symlink-test.sh b/test/lib/internals/create-symlink-test.sh
new file mode 100755
index 0000000..4164895
--- /dev/null
+++ b/test/lib/internals/create-symlink-test.sh
@@ -0,0 +1,50 @@
+#! /usr/bin/env bash
+source "../../test-helper.sh"
+source "../../../src/lib/internals.sh"
+
+#
+# create-symlink() tests
+#
+
+# Create temp files/folders used for create-symlink() tests.
+mkdir -p "tmp/source" "tmp/target"
+touch "tmp/source/profile"
+
+# Creates a normal symlink.
+assert_raises 'create-symlink ../source tmp/target/.dotfiles' 0
+assert 'readlink tmp/target/.dotfiles' "../source"
+rm "tmp/target/.dotfiles"
+
+# When target exists an is a symlink to the same source.
+ln -s "../source" "tmp/target/.dotfiles"
+assert_raises 'create-symlink ../source tmp/target/.dotfiles' 0
+assert 'create-symlink ../source tmp/target/.dotfiles 2>&1' ""
+rm "tmp/target/.dotfiles"
+
+# When target exists and is a symlink to a different source.
+ln -s "../other" "tmp/target/.dotfiles"
+assert_raises 'create-symlink ../source tmp/target/.dotfiles' 1
+assert 'create-symlink ../source tmp/target/.dotfiles' ""
+assert 'create-symlink ../source tmp/target/.dotfiles 2>&1' \
+  "ERROR: \"tmp/target/.dotfiles\" exists, is a symlink to: ../other"
+rm "tmp/target/.dotfiles"
+
+# When target exists and is a file.
+touch "tmp/target/.profile"
+assert_raises 'create-symlink ../source/profile tmp/target/.profile' 1
+assert 'create-symlink ../source/profile tmp/target/.profile' ""
+assert 'create-symlink ../source/profile tmp/target/.profile 2>&1' \
+  "ERROR: \"tmp/target/.profile\" exists"
+rm "tmp/target/.profile"
+
+# When target exists and is a directory.
+assert_raises 'create-symlink ../source tmp/target' 1
+assert 'create-symlink ../source tmp/target' ""
+assert 'create-symlink ../source tmp/target 2>&1' \
+  "ERROR: \"tmp/target\" exists"
+
+# Remove temp files/folders used for locate-dotfile() tests.
+rm "tmp/source/profile"
+rmdir "tmp/source" "tmp/target" "tmp"
+
+assert_end 'create-symlink()'
diff --git a/test/lib/internals-test.sh b/test/lib/internals/locate-dotfile-test.sh
similarity index 59%
rename from test/lib/internals-test.sh
rename to test/lib/internals/locate-dotfile-test.sh
index 75c46dd..f2f6562 100755
--- a/test/lib/internals-test.sh
+++ b/test/lib/internals/locate-dotfile-test.sh
@@ -1,9 +1,9 @@
 #! /usr/bin/env bash
-source "../test-helper.sh"
-source "../../src/lib/internals.sh"
+source "../../test-helper.sh"
+source "../../../src/lib/internals.sh"
 
 #
-# locate-dotfile()
+# locate-dotfile() tests
 #
 
 # Create temp files/folders used for locate-dotfile() tests.
@@ -49,37 +49,3 @@ assert_raises "test -d test-tmp" 1
 
 # End of locate-dotfile() tests.
 assert_end 'locate-dotfile()'
-
-
-#
-# locate-target()
-#
-
-# When $TARGET is empty.
-TARGET=""
-assert_raises 'locate-target' 0
-assert 'locate-target; echo "$TARGET"' "$HOME"
-unset TARGET
-
-# When $TARGET is not empty and is a directory.
-TARGET="$(pwd)"
-assert_raises 'locate-target' 0
-assert 'locate-target; echo "$TARGET"' "$(pwd)"
-unset TARGET
-
-# When $TARGET is not empty and is not a directory.
-TARGET="/tmp/this/does/not/exist"
-assert_raises 'locate-target' 1
-assert 'locate-target 2>&1' "ERROR: Target \"$TARGET\" is not a directory."
-assert 'locate-target; echo "$TARGET"' "$TARGET"
-unset TARGET
-
-# If neither $TARGET or $HOME is set, ~ is expanded to find home folder
-original_home="$HOME"
-unset HOME
-assert_raises 'locate-target' 0
-assert 'locate-target; echo "$TARGET"' "$original_home"
-HOME="$original_home"
-
-# End of locate-target() tests.
-assert_end 'locate-target()'
diff --git a/test/lib/internals/locate-target-test.sh b/test/lib/internals/locate-target-test.sh
new file mode 100755
index 0000000..89d7323
--- /dev/null
+++ b/test/lib/internals/locate-target-test.sh
@@ -0,0 +1,36 @@
+#! /usr/bin/env bash
+source "../../test-helper.sh"
+source "../../../src/lib/internals.sh"
+
+#
+# locate-target() tests
+#
+
+# When $TARGET is empty.
+TARGET=""
+assert_raises 'locate-target' 0
+assert 'locate-target; echo "$TARGET"' "$HOME"
+unset TARGET
+
+# When $TARGET is not empty and is a directory.
+TARGET="$(pwd)"
+assert_raises 'locate-target' 0
+assert 'locate-target; echo "$TARGET"' "$(pwd)"
+unset TARGET
+
+# When $TARGET is not empty and is not a directory.
+TARGET="/tmp/this/does/not/exist"
+assert_raises 'locate-target' 1
+assert 'locate-target 2>&1' "ERROR: Target \"$TARGET\" is not a directory."
+assert 'locate-target; echo "$TARGET"' "$TARGET"
+unset TARGET
+
+# If neither $TARGET or $HOME is set, ~ is expanded to find home folder
+original_home="$HOME"
+unset HOME
+assert_raises 'locate-target' 0
+assert 'locate-target; echo "$TARGET"' "$original_home"
+HOME="$original_home"
+
+# End of locate-target() tests.
+assert_end 'locate-target()'
diff --git a/test/lib/parse-dotfile-options-test.sh b/test/lib/internals/parse-dotfile-options-test.sh
similarity index 94%
rename from test/lib/parse-dotfile-options-test.sh
rename to test/lib/internals/parse-dotfile-options-test.sh
index 8157a81..0dc054e 100755
--- a/test/lib/parse-dotfile-options-test.sh
+++ b/test/lib/internals/parse-dotfile-options-test.sh
@@ -4,7 +4,7 @@ source "../../src/lib/parse-dotfile-options.sh"
 source "../../src/lib/trim.sh"
 
 #
-# parse-dotfile-options()
+# parse-dotfile-options() tests
 #
 
 stub "parse-dotfile-root_link-option"
@@ -24,7 +24,7 @@ assert_end "parse-dotfile-options()"
 
 
 #
-# parse-dotfile-option()
+# parse-dotfile-option() tests
 #
 
 # Create temp files/folders used for locate-dotfile() tests.
@@ -62,7 +62,7 @@ assert_end "parse-dotfile-option()"
 
 
 #
-# parse-dotfile-root_link-option()
+# parse-dotfile-root_link-option() tests
 #
 
 stub "parse-dotfile-option"
@@ -76,7 +76,7 @@ assert_end "parse-dotfile-root_link-option()"
 
 
 #
-# parse-dotfile-default_action-option()
+# parse-dotfile-default_action-option() tests
 #
 
 stub "parse-dotfile-option"