diff --git a/docs/requirements.readthedocs.txt b/docs/requirements.readthedocs.txt
index e287f2474b..52895048ed 120000
--- a/docs/requirements.readthedocs.txt
+++ b/docs/requirements.readthedocs.txt
@@ -1 +1 @@
-../requirements/docs.txt
\ No newline at end of file
+../requirements/docs_lock.txt
\ No newline at end of file
diff --git a/requirements/docs.txt b/requirements/docs.txt
index cdb1454448..01826c8bd8 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -3,7 +3,8 @@
 # documentation.
 
 # After editing this file, you MUST afterward run
-# /tools/update-locked-requirements to update requirements/dev_lock.txt.
+# /tools/update-locked-requirements to update requirements/dev_lock.txt
+# and requirements/docs_lock.txt.
 # See requirements/README.md for more detail.
 
 # Needed to build RTD docs
diff --git a/requirements/docs_lock.txt b/requirements/docs_lock.txt
new file mode 100644
index 0000000000..3a14721a22
--- /dev/null
+++ b/requirements/docs_lock.txt
@@ -0,0 +1,30 @@
+#
+# This file is GENERATED.  Don't edit directly.
+#
+# To update, edit the non-"lock" files in requirements/*.txt, then:
+#
+#    tools/update-locked-requirements
+#
+# For details, see requirements/README.md .
+#
+alabaster==0.7.10
+babel==2.5.1
+certifi==2017.11.5        # via requests
+chardet==3.0.4            # via requests
+commonmark==0.5.4
+docutils==0.14
+idna==2.6                 # via requests
+imagesize==0.7.1
+jinja2==2.10              # via sphinx
+markupsafe==1.0           # via jinja2
+pygments==2.2.0           # via sphinx
+pytz==2017.3              # via babel
+recommonmark==0.4.0
+requests==2.18.4          # via sphinx
+six==1.11.0               # via sphinx
+snowballstemmer==1.2.1
+sphinx-rtd-theme==0.2.4
+sphinx==1.6.5
+sphinxcontrib-websupport==1.0.1  # via sphinx
+typing==3.6.2             # via sphinx
+urllib3==1.22             # via requests
diff --git a/requirements/mypy.txt b/requirements/mypy.txt
index f64811ab23..b4c4b01f2e 100644
--- a/requirements/mypy.txt
+++ b/requirements/mypy.txt
@@ -1,4 +1,5 @@
 # After editing this file, you MUST afterward run
-# /tools/update-locked-requirements to update requirements/dev_lock.txt.
+# /tools/update-locked-requirements to update requirements/dev_lock.txt
+and requirements/mypy_lock.txt.
 # See requirements/README.md for more detail.
 mypy==0.540
diff --git a/requirements/mypy_lock.txt b/requirements/mypy_lock.txt
new file mode 100644
index 0000000000..54b59e260e
--- /dev/null
+++ b/requirements/mypy_lock.txt
@@ -0,0 +1,12 @@
+#
+# This file is GENERATED.  Don't edit directly.
+#
+# To update, edit the non-"lock" files in requirements/*.txt, then:
+#
+#    tools/update-locked-requirements
+#
+# For details, see requirements/README.md .
+#
+mypy==0.540
+typed-ast==1.1.0          # via mypy
+typing==3.6.2             # via mypy
diff --git a/tools/update-locked-requirements b/tools/update-locked-requirements
index f72f8f4add..064255aa31 100755
--- a/tools/update-locked-requirements
+++ b/tools/update-locked-requirements
@@ -43,25 +43,19 @@ EOF
     ) | sponge "$output"
 }
 
-OUTPUT_PROD_FILE='requirements/prod_lock.txt'
-OUTPUT_DEV_FILE='requirements/dev_lock.txt'
-OUTPUT_THUMBOR_FILE='requirements/thumbor_lock.txt'
+OUTPUT_BASE_DIR='requirements'
 
 # Parse arguments.
 if [ $# -gt 0 ]; then
     while [ "$1" != "" ]; do
         case $1 in
-            --prod)
+            --output-dir)
                 shift
-                OUTPUT_PROD_FILE="$1"
-                ;;
-            --dev)
-                shift
-                OUTPUT_DEV_FILE="$1"
+                OUTPUT_BASE_DIR=$(readlink -m "$1")
                 ;;
             *)
                 echo "Invalid arguments passed."
-                echo "Usage: $0 [--prod <prod-lock-file-path> --dev <dev-lock-file-path>]"
+                echo "Usage: $0 [--output-dir <path-to-output-dir>]"
                 exit
                 ;;
         esac
@@ -69,6 +63,8 @@ if [ $# -gt 0 ]; then
     done
 fi
 
-compile_requirements requirements/prod.txt $OUTPUT_PROD_FILE
-compile_requirements requirements/dev.txt $OUTPUT_DEV_FILE
-compile_requirements requirements/thumbor.txt $OUTPUT_THUMBOR_FILE py2
+compile_requirements requirements/prod.txt $OUTPUT_BASE_DIR/prod_lock.txt
+compile_requirements requirements/dev.txt $OUTPUT_BASE_DIR/dev_lock.txt
+compile_requirements requirements/mypy.txt $OUTPUT_BASE_DIR/mypy_lock.txt
+compile_requirements requirements/docs.txt $OUTPUT_BASE_DIR/docs_lock.txt
+compile_requirements requirements/thumbor.txt $OUTPUT_BASE_DIR/thumbor_lock.txt py2