diff --git a/pbf/README.md b/pbf/README.md
index 9db3b0a..bc103f0 100644
--- a/pbf/README.md
+++ b/pbf/README.md
@@ -1,19 +1,16 @@
 ## Overview
 
-tbc
+read pbf file from file system and print content to console
 
 ## Preparation
-Run the following command in your favorite terminal to install dependenies.
+
 ```
 npm i
 ```
 ## Development setup
-Run the following command if you fancy log messages for debugging.
+
 ```
 export DEBUG=$DEBUG,debug,pbf
-```
-Run the following command to start the service in development mode.
-```
 npm run dev
 ```
 ## Production deployment
diff --git a/pbf/package-lock.json b/pbf/package-lock.json
index 403215e..3f2e685 100644
--- a/pbf/package-lock.json
+++ b/pbf/package-lock.json
@@ -10,9 +10,9 @@
             "license": "GPL-3.0",
             "dependencies": {
                 "debug": "4.3.4",
-                "dotenv": "16.0.3",
-                "fs": "^0.0.1-security",
-                "pbf": "^3.2.1"
+                "dotenv": "16.3.1",
+                "fs": "0.0.1-security",
+                "pbf": "3.2.1"
             },
             "devDependencies": {
                 "nodemon": "2.0.19"
@@ -124,11 +124,14 @@
             }
         },
         "node_modules/dotenv": {
-            "version": "16.0.3",
-            "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.0.3.tgz",
-            "integrity": "sha512-7GO6HghkA5fYG9TYnNxi14/7K9f5occMlp3zXAuSxn7CKCxt9xbNWG7yF8hTCSUchlfWSe3uLmlPfigevRItzQ==",
+            "version": "16.3.1",
+            "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.3.1.tgz",
+            "integrity": "sha512-IPzF4w4/Rd94bA9imS68tZBaYyBWSCE47V1RGuMrB94iyTOIEwRmVL2x/4An+6mETpLrKJ5hQkB8W4kFAadeIQ==",
             "engines": {
                 "node": ">=12"
+            },
+            "funding": {
+                "url": "https://github.com/motdotla/dotenv?sponsor=1"
             }
         },
         "node_modules/fill-range": {
@@ -536,9 +539,9 @@
             }
         },
         "dotenv": {
-            "version": "16.0.3",
-            "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.0.3.tgz",
-            "integrity": "sha512-7GO6HghkA5fYG9TYnNxi14/7K9f5occMlp3zXAuSxn7CKCxt9xbNWG7yF8hTCSUchlfWSe3uLmlPfigevRItzQ=="
+            "version": "16.3.1",
+            "resolved": "https://registry.npmjs.org/dotenv/-/dotenv-16.3.1.tgz",
+            "integrity": "sha512-IPzF4w4/Rd94bA9imS68tZBaYyBWSCE47V1RGuMrB94iyTOIEwRmVL2x/4An+6mETpLrKJ5hQkB8W4kFAadeIQ=="
         },
         "fill-range": {
             "version": "7.0.1",
diff --git a/pbf/package.json b/pbf/package.json
index c8766d1..32c190b 100644
--- a/pbf/package.json
+++ b/pbf/package.json
@@ -15,7 +15,7 @@
     },
     "dependencies": {
         "debug": "4.3.4",
-        "dotenv": "16.0.3",
+        "dotenv": "16.3.1",
         "fs": "0.0.1-security",
         "pbf": "3.2.1"
     }