diff --git a/cleanup.py b/cleanup.py
index 1e71e05..2803cc3 100644
--- a/cleanup.py
+++ b/cleanup.py
@@ -13,6 +13,9 @@ class CleanerAgent:
 		self.rules_notanartist = [b for [a,b,c] in raw if a=="notanartist"]
 		self.rules_replacetitle = {b:c for [a,b,c] in raw if a=="replacetitle"}
 		self.rules_replaceartist = {b:c for [a,b,c] in raw if a=="replaceartist"}
+		
+		# we always need to be able to tell if our current database is made with the current rules
+		self.checksums = utilities.checksumTSV("rules")
 			
 	
 	
diff --git a/database.py b/database.py
index 7f611b1..f094cdf 100644
--- a/database.py
+++ b/database.py
@@ -511,7 +511,7 @@ def build_db():
 	
 	for f in os.listdir("scrobbles/"):
 		
-		if not (".tsv" in f):
+		if not (f.endswith(".tsv")):
 			continue
 		
 		logfile = open("scrobbles/" + f)
@@ -552,6 +552,24 @@ def sync():
 			monthfile.write("\n")
 			monthfile.close()
 			
+			if os.path.exists("scrobbles/" + str(timestamp.year) + "_" + str(timestamp.month) + ".tsv.rulestate"):
+				checkfile = open("scrobbles/" + str(timestamp.year) + "_" + str(timestamp.month) + ".tsv.rulestate","r")
+				print("Checking rulestate of " + str(timestamp.year) + "_" + str(timestamp.month) + ".tsv")
+				if checkfile.read() != cla.checksums:
+					print("Checksum does not match, file is inconsistent")
+					#cla.checksums represents the rule state that all current unsaved scrobbles were created under. if this is the same than the existing one, we're all good
+					#if not, the file is not consistent to any single rule state
+					checkfile.close()
+					checkfile = open("scrobbles/" + str(timestamp.year) + "_" + str(timestamp.month) + ".tsv.rulestate","w")
+					checkfile.write("INVALID") # this will never match any sha256sum
+				checkfile.close()
+			else:
+				print(str(timestamp.year) + "_" + str(timestamp.month) + ".tsv does not yet exist, writing current rulestate")
+				#if the file didn't exist before, all its scrobbles come from our current server instance and are therefore under the current rule state
+				checkfile = open("scrobbles/" + str(timestamp.year) + "_" + str(timestamp.month) + ".tsv.rulestate","w")
+				checkfile.write(cla.checksums)
+				checkfile.close()
+			
 			SCROBBLES[idx] = (SCROBBLES[idx][0],SCROBBLES[idx][1],True)
 			
 	global lastsync
diff --git a/fixexisting.py b/fixexisting.py
index 488f448..e584776 100644
--- a/fixexisting.py
+++ b/fixexisting.py
@@ -30,3 +30,7 @@ for fn in os.listdir("scrobbles/"):
 		fnew.close()
 		
 		os.rename("scrobbles/" + fn + "_new","scrobbles/" + fn)
+		
+		checkfile = open("scrobbles/" + fn + ".rulestate","w")
+		checkfile.write(wendigo.checksums)
+		checkfile.close()
diff --git a/lastfmconverter.py b/lastfmconverter.py
index 0567498..b6da66f 100644
--- a/lastfmconverter.py
+++ b/lastfmconverter.py
@@ -5,6 +5,7 @@ from utilities import *
 
 log = open(sys.argv[1])
 outputlog = open(sys.argv[2],"w")
+checksumfile = open(sys.argv[2] + ".rulestate","w") #this file stores an identifier for all rules that were in place when the corresponding file was created
 
 
 c = CleanerAgent()
@@ -34,7 +35,7 @@ for l in log:
 	
 	
 	## We prevent double timestamps in the database creation, so we technically don't need them in the files
-	## however since the conversion from lastfm to maloja is a one-time, thing, we should take any effort to make the file as good as possible
+	## however since the conversion from lastfm to maloja is a one-time thing, we should take any effort to make the file as good as possible
 	if (timestamp < stamps[-1]):
 		pass
 	elif (timestamp == stamps[-1]):
@@ -55,6 +56,11 @@ for l in log:
 	outputlog.write(entry)
 	outputlog.write("\n")
 	
+checksumfile.write(c.checksums)
+	
+log.close()
+outputlog.close()
+checksumfile.close()
 	
 
 
diff --git a/scrobbles/.gitignore b/scrobbles/.gitignore
index a59cd8e..abbcb8e 100644
--- a/scrobbles/.gitignore
+++ b/scrobbles/.gitignore
@@ -1,2 +1,3 @@
 *.tsv
 *.csv
+*.tsv.rulestate
diff --git a/utilities.py b/utilities.py
index 92f84e2..4d66576 100644
--- a/utilities.py
+++ b/utilities.py
@@ -36,6 +36,22 @@ def parseTSV(filename,*args):
 	f.close()
 	return result
 	
+def checksumTSV(folder):
+	import hashlib
+	import os
+	
+	sums = ""
+	
+	for f in os.listdir(folder + "/"):
+		if (f.endswith(".tsv")):
+			f = open(folder + "/" + f,"rb")
+			sums += hashlib.md5(f.read()).hexdigest() + "\n"
+			f.close()
+			
+	return sums
+	
+	
+	
 def parseAllTSV(path,*args):
 	
 	import os
diff --git a/website/maloja.css b/website/maloja.css
index 8d9ea42..945e4b3 100644
--- a/website/maloja.css
+++ b/website/maloja.css
@@ -57,7 +57,7 @@ table td.artists,td.artist,td.title,td.amount {
 }
 
 table td.button {
-	width:150px;
+	width:200px;
 	background-color:yellow;
 	color:#333337;
 	padding:1px;