diff --git a/app/crawler/main.sh b/app/crawler/main.sh
index a565844..896a6e1 100644
--- a/app/crawler/main.sh
+++ b/app/crawler/main.sh
@@ -13,9 +13,11 @@ main() {
 config() {
    set -o pipefail
    set -e
-   export CACHE=$(mktemp -d)
+   export CACHE="${CACHE:-"$(mktemp -d)"}"
+   export CACHE_DURATION=$((60*5))
    export CRAWL_INTERVAL=$((60*5))
    export NOTEA_ADDR="${NOTEA_ADDR:-"http://localhost:3000"}"
+   export GITLAB_PAT="$GITLAB_PAT"
 }
 
 log() {
@@ -27,7 +29,7 @@ ids() {
 }
 
 should_crawl() {
-   local f="$CACHE/crawled_$1"
+   local f="$CACHE/crawled.$1"
    if [ ! -f "$f" ]; then
       return 0
    fi
@@ -46,7 +48,21 @@ crawl() {
    if ! is_crawlable "$content"; then
       return 0
    fi
-   log not impl crawl
+   local crawlable_source="$(echo "$content" | head -n 1 | awk '{print $NF}')"
+   for backend in gitlab; do
+      if $backend is "$crawlable_source"; then
+         crawl_with $backend "$json"
+         return $?
+      fi
+   done
+   log "unknown backend for $crawlable_source"
+   return 1
+}
+
+crawl_with() {
+   local backend="$1"
+   local json="$2"
+   log not impl crawl with
    return 1
 }
 
@@ -80,11 +96,11 @@ notea() (
    }
 
    get() {
-      local cached="$CACHE/cache_$1"
-      if [ -f "$cached" ] && cat "$cached" | grep .; then
+      local cache_key="notea cache $1"
+      if cache get "$cache_key"; then
          return 0
       fi
-      _get "$@" | tee "$cached"
+      _get "$@" | cache put "$cache_key"
    }
 
    _get() {
@@ -94,9 +110,133 @@ notea() (
    "$@"
 )
 
-crawler() (
-   should() {
+cache() (
+   path() {
+      echo "$CACHE/$(echo "$*" | base64)"
    }
+   get() {
+      local path="$(path "$*")"
+      if ! [ -f "$path" ]; then
+         return 1
+      fi
+      if wc -c "$path" | grep -q '^[ ]*0[ ]*$'; then
+         return 1
+      fi
+      local created="$(date -r "$path" +%s)"
+      local now="$(date +%s)"
+      if ((now-created > CACHE_DURATION)); then
+         return 1
+      fi
+      cat "$path"
+   }
+   put() {
+      local path="$(path "$*")"
+      tee "$path"
+   }
+   "$@"
+)
+
+gitlab() (
+   is() {
+      echo "$*" | grep -q gitlab.app && ! echo "$*" | grep -q '/wiki/'
+   }
+
+   gcurl() {
+      local cache_key="gitlab gcurl $*"
+      if cache get "$cache_key"; then
+         return 0
+      fi
+      _gcurl "$@" | cache put "$cache_key"
+   }
+
+   _gcurl() {
+      curl -sS -H "Authorization: Bearer $GITLAB_PAT" "$@"
+   }
+
+   expand() {
+      local cache_key="gitlab expand $*"
+      if cache get "$cache_key"; then
+         return 0
+      fi
+      _expand "$@" | sort | cache put "$cache_key"
+   }
+
+   _expand() {
+      local url="$1"
+      local project="$(url_to_project_root "$url" | head -n 1)"
+      local root="$(url_to_project_root "$url" | tail -n 1)"
+      __expand "$project" "$root"
+   }
+
+   url_to_project_root() {
+      local url="$1"
+      local url_path="${url#http*://gitlab*.net/}"
+      local project="${url_path%%/-/*}"
+      local root="${url_path#*/-/}"
+      local root="${root#tree/}"
+      local root="${root#blob/}"
+      local root="${root#*/}"
+      echo "$project"
+      echo "$root"
+   }
+
+   __expand() {
+      local project="$1"
+      local root="${2:-"/"}"
+
+      local b64_files=()
+      local b64_trees=("$root")
+      local i=0
+
+      find_each() {
+         local type="$1"
+         shift
+         echo "$*" \
+            | jq -c .[] \
+            | grep "\"type\":\"$type\"" \
+            | jq -r .path \
+            | while read -r line; do echo "$line" | base64; done \
+            | grep .
+      }
+      while [ "$i" -lt "${#b64_trees[@]}" ]; do
+         got="$(list_tree "$project" "${b64_trees[i]}")"
+         for b64_tree in $(find_each "tree" "$got"); do
+            if ! echo "${b64_trees[@]}" | grep -q "[ ^]$b64_tree[ $]"; then
+               b64_trees+=("$b64_tree")
+            fi
+         done
+         for b64_file in $(find_each "blob" "$got"); do
+            if ! echo "${b64_files[@]}" | grep -q "[ ^]$b64_file[ $]"; then
+               b64_files+=("$b64_file")
+            fi
+         done
+         i=$((i+1))
+      done
+      for b64_file in "${b64_files[@]}"; do
+         echo "$b64_file" | base64 --decode
+      done
+   }
+
+   list_tree() {
+      local project="$(urlencode "$1")"
+      local path="/api/v4/projects/$project/repository/tree"
+      local query="recursive=true&path=$2"
+      gcurl "https://gitlab-app.eng.qops.net/$path?$query"
+   }
+
+   "$@"
+)
+
+urlencode() (
+    LC_COLLATE=C
+    local length="${#1}"
+    for (( i = 0; i < length; i++ )); do
+        local c="${1:$i:1}"
+        case $c in
+            [a-zA-Z0-9.~_-]) printf '%s' "$c" ;;
+            *) printf '%%%02X' "'$c" ;;
+        esac
+    done
 )
 
 if [ "$0" == "$BASH_SOURCE" ]; then