diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000000000000000000000000000000000000..048ffb1bb2c0619018bf1aeb6b5b7b7b5951e576
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,14 @@
+from ubuntu:20.04
+maintainer root@recolic.net
+
+run apt update && apt install -y fish wget curl
+run wget https://git.recolic.net/root/json2table/uploads/63b923b53a191968f0dc29cd988d7b4f/json2table-linux-static -O /usr/bin/json2table && chmod +x /usr/bin/json2table
+
+run mkdir -p /app
+copy . /app
+workdir /app
+
+cmd "./gitlab2github_daemon.fish"
+
+
+
diff --git a/README.md b/README.md
index f1a134c828fa7102b2bb4284434cc43d17a497a0..5dc61583f403a78eaa959560e4f1a4faca4e39b2 100644
--- a/README.md
+++ b/README.md
@@ -8,3 +8,11 @@ Dependencies: fish, json2table, git
 
 This doesn't recursively resolve gitlab sub-group. Please specify every sub-group as a new namespace. 
 
+## Usage
+
+```
+sudo docker build -f Dockerfile -t recolic/gitlab2github .
+sudo docker run -d --name rgitsync --env github_user_dst="rtestgithubapi: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" recolic/gitlab2github
+```
+
+
diff --git a/gitlab2github_daemon.fish b/gitlab2github_daemon.fish
new file mode 100755
index 0000000000000000000000000000000000000000..6db878cbb03da35ad63ba9078e3abc7a752ec56d
--- /dev/null
+++ b/gitlab2github_daemon.fish
@@ -0,0 +1,8 @@
+#!/usr/bin/fish
+
+while true
+    fish ./gitlab2github_sync.fish
+    echo "Sleeping 3600s..." 1>&2
+    sleep 3600
+end
+
diff --git a/gitlab2github_sync.fish b/gitlab2github_sync.fish
old mode 100644
new mode 100755
index b463db49ea81b23c8b3309e77f78c07e1b48f591..83655cab117f0739ace2f7f03a4dc35f9d60dc5c
--- a/gitlab2github_sync.fish
+++ b/gitlab2github_sync.fish
@@ -3,7 +3,11 @@
 set gitlab_host https://git.recolic.net
 # set gitlab_namespace_src users/root groups/recolic-hust
 set gitlab_namespace_src users/root
-set github_user_dst "rtestgithubapi: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"
+if test "$github_user_dst" = ""
+    echo 'Error: please set environment variable github_user_dst' 1>&2
+    echo 'Example: env github_user_dst="rtestgithubapi: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" ./gitlab2gitlab.fish'
+    exit 1
+end
 
 function echo2
     echo $argv 1>&2