Index: backend/subjects/management/commands/tag_graph.py
===================================================================
--- backend/subjects/management/commands/tag_graph.py	(revision 741c170ac6ca950d69c21216cecfd3162590c871)
+++ backend/subjects/management/commands/tag_graph.py	(revision 999cc854166225b363bfab41d717d532fd37233f)
@@ -69,8 +69,22 @@
     ("Mathematics", "AI / ML", 3),
     ("Data Science", "Mathematics", 3),
-    ("Mathematics", "Data Science", 3)
+    ("Mathematics", "Data Science", 3),
+    ("Software Engineering", "Systems Infrastructure", 0.5),
+    ("Systems Infrastructure", "Software Engineering", 0.5),
+    ("Web Development", "Software Engineering", 1.5),
+    ("Software Engineering", "Web Development", 1.5),
+    ("Software Engineering", "Cloud Engineering & DevOps", 0.5),
+    ("Cloud Engineering & DevOps", "Software Engineering", 1),
+    ("Software Engineering", "Databases", 1.5),
+    ("Databases", "Software Engineering", 1.5),
+    ("Software Engineering", "Computer Science", 1),
+    ("Computer Science", "Software Engineering", 1)
 ]
 
 def add(tag_graph, tag1, tag2, weight):
+    if tag1 not in tag_graph:
+        raise Exception(f"tag '{tag1}' not found in graph.")
+    if tag2 not in tag_graph:
+        raise Exception(f"tag '{tag2}' not found in graph.")
     tag_graph[tag1].append((tag2, weight))
 
Index: backend/subjects/management/data/additional_info.json
===================================================================
--- backend/subjects/management/data/additional_info.json	(revision 741c170ac6ca950d69c21216cecfd3162590c871)
+++ backend/subjects/management/data/additional_info.json	(revision 999cc854166225b363bfab41d717d532fd37233f)
@@ -448,5 +448,5 @@
 	{
 		"name": "Веб програмирање",
-		"tags": ["Web Development", "Software Engineering"],
+		"tags": ["Web Development", "Software Engineering", "Databases"],
 		"technologies": ["Spring"],
 		"isEasy": false,
Index: backend/subjects/management/data/subject_details.json
===================================================================
--- backend/subjects/management/data/subject_details.json	(revision 741c170ac6ca950d69c21216cecfd3162590c871)
+++ backend/subjects/management/data/subject_details.json	(revision 999cc854166225b363bfab41d717d532fd37233f)
@@ -1590,5 +1590,5 @@
 			"Дарко Сасански"
 		],
-		"tags": ["Web Development", "Software Engineering"],
+		"tags": ["Web Development", "Software Engineering", "Databases"],
 		"technologies": ["Spring"],
 		"evaluation": ["Theory", "Code", "Project"],
Index: backend/subjects/management/data/tag_graph.json
===================================================================
--- backend/subjects/management/data/tag_graph.json	(revision 741c170ac6ca950d69c21216cecfd3162590c871)
+++ backend/subjects/management/data/tag_graph.json	(revision 999cc854166225b363bfab41d717d532fd37233f)
@@ -7,5 +7,6 @@
 	"1": [
 		[12, 0.75],
-		[18, 1.5]
+		[18, 1.5],
+		[15, 1]
 	],
 	"2": [
@@ -18,5 +19,6 @@
 		[10, 1],
 		[13, 0.33],
-		[2, 0.5]
+		[2, 0.5],
+		[15, 1]
 	],
 	"4": [
@@ -31,5 +33,6 @@
 	"6": [
 		[18, 2],
-		[0, 1.5]
+		[0, 1.5],
+		[15, 1.5]
 	],
 	"7": [[14, 1]],
@@ -59,8 +62,15 @@
 	],
 	"14": [[7, 1]],
-	"15": [],
+	"15": [
+		[16, 0.5],
+		[18, 1.5],
+		[1, 0.5],
+		[6, 1.5],
+		[3, 1]
+	],
 	"16": [
 		[4, 1],
-		[2, 1]
+		[2, 1],
+		[15, 0.5]
 	],
 	"17": [
@@ -71,5 +81,6 @@
 		[6, 2],
 		[1, 1.5],
-		[17, 2]
+		[17, 2],
+		[15, 1.5]
 	]
 }