diff --git a/.gitignore b/.gitignore
new file mode 100644
index 00000000..1fb9ef57
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+tmp/*
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 14796915..6f1ad485 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: alpine:latest # Use latest version of Alpine Linux docker image
+image: alpine:latest # Use the latest version of Alpine Linux docker image
 
 before_script:
   # Install dependencies
@@ -33,21 +33,10 @@ deploy:
     # Change to the downloaded repo directory
     - cd build/
 
-    # Give execute permission to scripts
-    - cd utils/
-    - chmod 700 umbrella-top-1m.sh script.sh commit.sh
-
-    # Download Umbrella Popularity List
-    - ./umbrella-top-1m.sh
-
-    # Download database dump and process it
-    - ./script.sh
-
-    # Commit the changes
-    - ./commit.sh
+    # Execute script.sh
+    - sh utils/script.sh
 
     # Push the commit
-    - cd ../
     - git push
 
   only:
diff --git a/README.md b/README.md
index 467a7a87..3babc3c5 100644
--- a/README.md
+++ b/README.md
@@ -16,16 +16,6 @@ Mirrors:
 - https://glcdn.githack.com/curben/urlhaus-filter/raw/master/urlhaus-filter.txt
 - https://cdn.staticaly.com/gl/curben/urlhaus-filter/raw/master/urlhaus-filter.txt
 
-## Description
-
-Following URL categories are removed from the database dump:
-
-- Offline URLs
-- Well-known domains from the [Umbrella Popularity List](https://s3-us-west-1.amazonaws.com/umbrella-static/index.html).
-- False positives ([exclude.txt](src/exclude.txt))
-
-Database dump is saved as [URLhaus.csv](src/URLhaus.csv), get processed by [script.sh](utils/script.sh) and output as [urlhaus-filter.txt](urlhaus-filter.txt).
-
 ## Compatibility
 
 This filter is only tested with uBO. [FilterLists](https://filterlists.com/) shows it is compatible with the following software:
@@ -40,11 +30,13 @@ This filter is only tested with uBO. [FilterLists](https://filterlists.com/) sho
 - [Samsung Knox](https://www.samsungknox.com/)
 - [uMatrix](https://github.com/gorhill/uMatrix)
 
+Note that some of the software above are host-based only, meaning it cannot block malware URLs hosted by well-known domains (e.g. amazonaws.com, docs.google.com, dropbox.com). For best compatibility, use uBO or its fork NanoAdblocker.
+
 ## Issues
 
-Report any false positive by creating an [issue](https://gitlab.com/curben/urlhaus-filter/issues).
+Report any false positive by creating an [issue](https://gitlab.com/curben/urlhaus-filter/issues) or [merge request](https://gitlab.com/curben/urlhaus-filter/merge_requests)
 
-This filter **only** accepts malware URLs from the [URLhaus](https://urlhaus.abuse.ch/).
+This filter **only** accepts malware URLs from [URLhaus](https://urlhaus.abuse.ch/).
 
 Please report new malware URL to the upstream maintainer through https://urlhaus.abuse.ch/api/#submit.
 
@@ -54,7 +46,7 @@ This repo is not endorsed by Abuse.sh.
 
 Since the filter is updated frequently, cloning the repo would become slower over time as the revision grows.
 
-Use shallow clone to get the recent revisions only. Getting the last five revisions is sufficient for a valid MR.
+Use shallow clone to get the recent revisions only. Getting the last five revisions should be sufficient for a valid MR.
 
 `git clone --depth 5 https://gitlab.com/curben/urlhaus-filter.git`
 
diff --git a/utils/commit.sh b/utils/commit.sh
old mode 100755
new mode 100644
index 7fe7a801..033936a5
--- a/utils/commit.sh
+++ b/utils/commit.sh
@@ -1,6 +1,9 @@
 #!/bin/sh
 
-# Commit the filter update
+## Commit the filter update
+
+## GitLab CI does not permit shell variable in .gitlab-ci.yml.
+## This file is a workaround for that.
 
 CURRENT_TIME="$(date -R -u)"
 git commit -a -m "Filter updated: $CURRENT_TIME"
diff --git a/utils/malware-domains.sh b/utils/malware-domains.sh
new file mode 100644
index 00000000..d4632fc8
--- /dev/null
+++ b/utils/malware-domains.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+
+## Parse domains from URLhaus excluding popular domains
+
+cat URLhaus.csv | \
+# Convert DOS to Unix line ending
+dos2unix | \
+# Parse online URLs only
+grep '"online"' | \
+# Parse domains and IP address only
+cut -f 6 -d '"' | \
+cut -f 3 -d '/' | \
+cut -f 1 -d ':' | \
+# Remove www
+# Only matches domains that start with www
+# Not examplewww.com
+sed -e 's/^www\.//g' | \
+# Sort and remove duplicates
+sort -u | \
+# Exclude Umbrella Top 1M and well-known domains
+# grep inverse match whole line
+grep -Fx -vf top-1m-well-known.txt > malware-domains.txt
diff --git a/utils/malware-url-top-domains.sh b/utils/malware-url-top-domains.sh
new file mode 100644
index 00000000..445f55e1
--- /dev/null
+++ b/utils/malware-url-top-domains.sh
@@ -0,0 +1,21 @@
+#!/bin/sh
+
+## Parse malware URLs from popular URLhaus domains
+
+cat URLhaus.csv | \
+# Convert DOS to Unix line ending
+dos2unix | \
+# Parse online URLs only
+grep '"online"' | \
+# Parse URLs
+cut -f 6 -d '"' | \
+cut -f 3- -d '/' | \
+cut -f 1- -d ':' | \
+# Remove www
+# Only matches domains that start with www
+# Not examplewww.com
+sed -e 's/^www\.//g' | \
+# Sort and remove duplicates
+sort -u | \
+# Include URLs from popular domains
+grep -F -f urlhaus-top-domains.txt > malware-url-top-domains.txt
diff --git a/utils/prerequisites.sh b/utils/prerequisites.sh
new file mode 100644
index 00000000..dca0f2c0
--- /dev/null
+++ b/utils/prerequisites.sh
@@ -0,0 +1,10 @@
+#!/bin/sh
+
+# Download URLhaus database
+wget https://urlhaus.abuse.ch/downloads/csv/ -O ../src/URLhaus.csv
+
+# Download Cisco Umbrella 1 Million
+wget https://s3-us-west-1.amazonaws.com/umbrella-static/top-1m.csv.zip -O top-1m.csv.zip
+
+cp ../src/URLhaus.csv .
+cp ../src/exclude.txt .
diff --git a/utils/script.sh b/utils/script.sh
old mode 100755
new mode 100644
index 2ebe574e..d571d5ab
--- a/utils/script.sh
+++ b/utils/script.sh
@@ -1,40 +1,15 @@
 #!/bin/sh
 
-# Download the URLhaus database dump and process it to be uBO-compatible
+mkdir tmp/
+cd tmp/
 
-CURRENT_TIME="$(date -R -u)"
-FIRST_LINE="! Title: abuse.ch URLhaus Malicious URL Blocklist"
-SECOND_LINE="! Updated: $CURRENT_TIME"
-THIRD_LINE="! Expires: 1 day (update frequency)"
-FOURTH_LINE="! Repo: https://gitlab.com/curben/urlhaus-filter"
-FIFTH_LINE="! License: https://creativecommons.org/publicdomain/zero/1.0/"
-SIXTH_LINE="! Source: https://urlhaus.abuse.ch/api/"
-COMMENT="$FIRST_LINE\n$SECOND_LINE\n$THIRD_LINE\n$FOURTH_LINE\n$FIFTH_LINE\n$SIXTH_LINE"
+sh ../utils/prerequisites.sh
+sh ../utils/umbrella-top-1m.sh
+sh ../utils/malware-domains.sh
+sh ../utils/urlhaus-top-domains.sh
+sh ../utils/malware-url-top-domains.sh
+sh ../utils/urlhaus-filter.sh
+sh ../utils/commit.sh
 
-# Download the database dump
-wget https://urlhaus.abuse.ch/downloads/csv/ -O ../src/URLhaus.csv
-
-cat ../src/URLhaus.csv | \
-# Convert DOS to Unix line ending
-dos2unix | \
-# Parse online URLs only
-grep '"online"' | \
-# Parse domains and IP address only
-cut -f 6 -d '"' | \
-cut -f 3 -d '/' | \
-cut -f 1 -d ':' | \
-# Remove www
-# Only matches domains that start with www
-# Not examplewww.com
-sed -e 's/^www\.//g' | \
-# Sort and remove duplicates
-sort -u | \
-# Exclude Umbrella Top 1M. grep inverse match whole line
-grep -Fx -vf ../src/top-1m.txt | \
-# Exclude false positive
-grep -Fx -vf ../src/exclude.txt | \
-# Append header comment to the filter list
-sed '1 i\'"$COMMENT"'' > ../urlhaus-filter.txt
-
-# Remove downloaded dataset
-rm ../src/top-1m.txt
+cd ../
+rm -r tmp/
diff --git a/utils/umbrella-top-1m.sh b/utils/umbrella-top-1m.sh
old mode 100755
new mode 100644
index 59b8f598..751f61b4
--- a/utils/umbrella-top-1m.sh
+++ b/utils/umbrella-top-1m.sh
@@ -1,11 +1,8 @@
 #!/bin/sh
 
-# Download the Cisco Umbrella 1 Million
-# More info:
-# https://s3-us-west-1.amazonaws.com/umbrella-static/index.html
-
-# Download the list
-wget https://s3-us-west-1.amazonaws.com/umbrella-static/top-1m.csv.zip -O top-1m.csv.zip
+## Parse the Cisco Umbrella 1 Million
+## More info:
+## https://s3-us-west-1.amazonaws.com/umbrella-static/index.html
 
 # Decompress the zip and write output to stdout
 unzip -p top-1m.csv.zip | \
@@ -13,12 +10,15 @@ unzip -p top-1m.csv.zip | \
 dos2unix | \
 # Parse domains only
 cut -f 2 -d ',' | \
+# Domain must have at least a 'dot'
+grep -F '.' | \
 # Remove www
 # Only matches domains that start with www
 # Not examplewww.com
 sed -e 's/^www\.//g' | \
 # Remove duplicates
-sort -u > ../src/top-1m.txt
+sort -u > top-1m.txt
 
-# Remove downloaded zip file
-rm top-1m.csv.zip
+# Merge Umbrella and self-maintained top domains
+cat top-1m.txt exclude.txt | \
+sort -u > top-1m-well-known.txt
diff --git a/utils/urlhaus-filter.sh b/utils/urlhaus-filter.sh
new file mode 100644
index 00000000..8e2c87f7
--- /dev/null
+++ b/utils/urlhaus-filter.sh
@@ -0,0 +1,20 @@
+#!/bin/sh
+
+## Merge malware-domains.txt malware-url-top-domains.txt,
+## and append a header to instruct uBO to grab the filter daily.
+
+
+CURRENT_TIME="$(date -R -u)"
+FIRST_LINE="! Title: abuse.ch URLhaus Malicious URL Blocklist"
+SECOND_LINE="! Updated: $CURRENT_TIME"
+THIRD_LINE="! Expires: 1 day (update frequency)"
+FOURTH_LINE="! Repo: https://gitlab.com/curben/urlhaus-filter"
+FIFTH_LINE="! License: https://creativecommons.org/publicdomain/zero/1.0/"
+SIXTH_LINE="! Source: https://urlhaus.abuse.ch/api/"
+COMMENT="$FIRST_LINE\n$SECOND_LINE\n$THIRD_LINE\n$FOURTH_LINE\n$FIFTH_LINE\n$SIXTH_LINE"
+
+cat malware-domains.txt malware-url-top-domains.txt | \
+# Sort alphabetically
+sort | \
+# Append header comment to the filter list
+sed '1 i\'"$COMMENT"'' > ../urlhaus-filter.txt
diff --git a/utils/urlhaus-top-domains.sh b/utils/urlhaus-top-domains.sh
new file mode 100644
index 00000000..e8d3484d
--- /dev/null
+++ b/utils/urlhaus-top-domains.sh
@@ -0,0 +1,22 @@
+#!/bin/sh
+
+## Parse popular domains from URLhaus
+
+cat URLhaus.csv | \
+# Convert DOS to Unix line ending
+dos2unix | \
+# Parse online URLs only
+grep '"online"' | \
+# Parse domains and IP address only
+cut -f 6 -d '"' | \
+cut -f 3 -d '/' | \
+cut -f 1 -d ':' | \
+# Remove www
+# Only matches domains that start with www
+# Not examplewww.com
+sed -e 's/^www\.//g' | \
+# Sort and remove duplicates
+sort -u | \
+# Exclude Umbrella Top 1M and well-known domains
+# grep inverse match whole line
+grep -Fx -f top-1m-well-known.txt > urlhaus-top-domains.txt