diff --git a/src/FilterLists.Services/Extensions/CollectionExtensions.cs b/src/FilterLists.Services/Extensions/CollectionExtensions.cs
deleted file mode 100644
index 81957558d..000000000
--- a/src/FilterLists.Services/Extensions/CollectionExtensions.cs
+++ /dev/null
@@ -1,17 +0,0 @@
-using System.Collections.Generic;
-
-namespace FilterLists.Services.Extensions
-{
-    public static class CollectionExtensions
-    {
-        //https://stackoverflow.com/a/26360010/2343739
-        public static void AddRange<T>(this ICollection<T> destination, IEnumerable<T> source)
-        {
-            if (destination is List<T> list)
-                list.AddRange(source);
-            else
-                foreach (var item in source)
-                    destination.Add(item);
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/FilterLists.Services/Extensions/EnumerableExtensions.cs b/src/FilterLists.Services/Extensions/EnumerableExtensions.cs
new file mode 100644
index 000000000..d6594d702
--- /dev/null
+++ b/src/FilterLists.Services/Extensions/EnumerableExtensions.cs
@@ -0,0 +1,29 @@
+using System.Collections.Generic;
+
+namespace FilterLists.Services.Extensions
+{
+    public static class EnumerableExtensions
+    {
+        public static void AddRange<T>(this ICollection<T> destination, IEnumerable<T> source)
+        {
+            foreach (var item in source)
+                destination.Add(item);
+        }
+
+        public static IEnumerable<IEnumerable<T>> GetBatches<T>(this IEnumerable<T> source, int batchSize)
+        {
+            var batches = new List<T>(batchSize);
+            foreach (var item in source)
+            {
+                batches.Add(item);
+                if (batches.Count != batchSize)
+                    continue;
+                yield return batches.AsReadOnly();
+                batches = new List<T>(batchSize);
+            }
+
+            if (batches.Count > 0)
+                yield return batches.AsReadOnly();
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/FilterLists.Services/FilterLists.Services.csproj b/src/FilterLists.Services/FilterLists.Services.csproj
index b5df087db..6eb37a229 100644
--- a/src/FilterLists.Services/FilterLists.Services.csproj
+++ b/src/FilterLists.Services/FilterLists.Services.csproj
@@ -20,7 +20,6 @@
     <PackageReference Include="JetBrains.Annotations" Version="2018.2.1" />
     <PackageReference Include="Microsoft.ApplicationInsights.AspNetCore" Version="2.4.0" />
     <PackageReference Include="Microsoft.DotNet.Analyzers.Compatibility" Version="0.2.12-alpha" />
-    <PackageReference Include="morelinq" Version="3.0.0" />
     <PackageReference Include="SendGrid" Version="9.9.0" />
   </ItemGroup>
 
diff --git a/src/FilterLists.Services/Snapshot/RawRuleLinterExtensions.cs b/src/FilterLists.Services/Snapshot/RawRuleLinterExtensions.cs
index cd4a28d4f..cfe0c95e9 100644
--- a/src/FilterLists.Services/Snapshot/RawRuleLinterExtensions.cs
+++ b/src/FilterLists.Services/Snapshot/RawRuleLinterExtensions.cs
@@ -1,38 +1,35 @@
-using System;
-
-namespace FilterLists.Services.Snapshot
+namespace FilterLists.Services.Snapshot
 {
     public static class RawRuleLinterExtensions
     {
         public static string LintRawRule(this string rule)
         {
-            rule = rule.Trim();
-            rule = rule.DropIfEmpty();
-            rule = rule?.DropIfTooLong();
+            rule = rule?.TrimLeadingAndTrailingWhitespace();
+            rule = rule?.DropIfEmpty();
             rule = rule?.DropIfComment();
+            rule = rule?.DropIfTooLong();
             rule = rule?.DropIfContainsBackslashSingleQuote();
             rule = rule?.TrimSingleBackslashFromEnd();
             return rule;
         }
 
-        private static string DropIfEmpty(this string rule) =>
-            rule == string.Empty ? null : rule;
-        
-        private static string DropIfTooLong(this string rule) =>
-            rule.Length > 8192 ? null : rule;
-        
+        private static string TrimLeadingAndTrailingWhitespace(this string rule)
+        {
+            char[] charsToTrim = {' ', '\t'};
+            return rule.Trim(charsToTrim);
+        }
+
+        private static string DropIfEmpty(this string rule) => rule == "" ? null : rule;
+
         private static string DropIfComment(this string rule) =>
-            rule.StartsWith(@"!", StringComparison.Ordinal) && !rule.StartsWith(@"!#", StringComparison.Ordinal) ||
-            rule.StartsWith(@"!##", StringComparison.Ordinal)
-                ? null
-                : rule;
+            rule.StartsWith(@"!") && !rule.StartsWith(@"!#") || rule.StartsWith(@"!##") ? null : rule;
+
+        private static string DropIfTooLong(this string rule) => rule.Length > 8192 ? null : rule;
 
         private static string DropIfContainsBackslashSingleQuote(this string rule) =>
             rule.Contains(@"\'") ? null : rule;
 
         private static string TrimSingleBackslashFromEnd(this string rule) =>
-            rule.EndsWith(@"\", StringComparison.Ordinal) && !rule.EndsWith(@"\\", StringComparison.Ordinal)
-                ? rule.Remove(rule.Length - 1)
-                : rule;
+            rule.EndsWith(@"\") && !rule.EndsWith(@"\\") ? rule.Remove(rule.Length - 1) : rule;
     }
 }
\ No newline at end of file
diff --git a/src/FilterLists.Services/Snapshot/SnapshotDeBatch.cs b/src/FilterLists.Services/Snapshot/SnapshotBatchDe.cs
similarity index 63%
rename from src/FilterLists.Services/Snapshot/SnapshotDeBatch.cs
rename to src/FilterLists.Services/Snapshot/SnapshotBatchDe.cs
index 13e35cbb0..555f5bc5c 100644
--- a/src/FilterLists.Services/Snapshot/SnapshotDeBatch.cs
+++ b/src/FilterLists.Services/Snapshot/SnapshotBatchDe.cs
@@ -8,14 +8,14 @@
 
 namespace FilterLists.Services.Snapshot
 {
-    public class SnapshotDeBatch
+    public class SnapshotBatchDe
     {
         private readonly FilterListsDbContext dbContext;
         private readonly IEnumerable<string> rawRules;
         private readonly Data.Entities.Snapshot snapshot;
-        private IEnumerable<Rule> rules;
+        private IQueryable<Rule> rules;
 
-        public SnapshotDeBatch(FilterListsDbContext dbContext, Data.Entities.Snapshot snapshot,
+        public SnapshotBatchDe(FilterListsDbContext dbContext, Data.Entities.Snapshot snapshot,
             IEnumerable<string> rawRules)
         {
             this.dbContext = dbContext;
@@ -23,7 +23,7 @@ public SnapshotDeBatch(FilterListsDbContext dbContext, Data.Entities.Snapshot sn
             this.rawRules = rawRules;
         }
 
-        public async Task SaveAsync()
+        public async Task SaveSnapshotBatchAsync()
         {
             await AddRules();
             AddSnapshotRules();
@@ -32,18 +32,18 @@ public async Task SaveAsync()
 
         private async Task AddRules()
         {
-            var existingRules = GetExistingRules();
-            var newRules = CreateNewRules(existingRules);
+            var existingRules = dbContext.Rules.Where(r => rawRules.Contains(r.Raw));
+            var newRawRules = rawRules.Except(existingRules.Select(r => r.Raw));
+            var newRules = newRawRules.Select(r => new Rule {Raw = r}).ToList();
             rules = existingRules.Concat(newRules);
             await dbContext.Rules.AddRangeAsync(newRules);
         }
 
-        private IQueryable<Rule> GetExistingRules() => dbContext.Rules.Where(r => rawRules.Contains(r.Raw));
-
-        private List<Rule> CreateNewRules(IQueryable<Rule> existingRules) =>
-            rawRules.Except(existingRules.Select(r => r.Raw)).Select(r => new Rule {Raw = r}).ToList();
-
-        private void AddSnapshotRules() =>
+        private void AddSnapshotRules()
+        {
+            if (snapshot.AddedSnapshotRules == null)
+                snapshot.AddedSnapshotRules = new List<SnapshotRule>();
             snapshot.AddedSnapshotRules.AddRange(rules.Select(r => new SnapshotRule {Rule = r}));
+        }
     }
 }
\ No newline at end of file
diff --git a/src/FilterLists.Services/Snapshot/SnapshotDe.cs b/src/FilterLists.Services/Snapshot/SnapshotDe.cs
index 1d94a8062..b661d4bd1 100644
--- a/src/FilterLists.Services/Snapshot/SnapshotDe.cs
+++ b/src/FilterLists.Services/Snapshot/SnapshotDe.cs
@@ -7,8 +7,8 @@
 using System.Threading.Tasks;
 using FilterLists.Data;
 using FilterLists.Data.Entities.Junctions;
+using FilterLists.Services.Extensions;
 using FilterLists.Services.Snapshot.Models;
-using MoreLinq;
 
 namespace FilterLists.Services.Snapshot
 {
@@ -28,14 +28,10 @@ public SnapshotDe(FilterListsDbContext dbContext, EmailService emailService, Fil
             this.dbContext = dbContext;
             this.emailService = emailService;
             this.list = list;
-            snapshot = new Data.Entities.Snapshot
-            {
-                FilterListId = list.Id,
-                AddedSnapshotRules = new List<SnapshotRule>()
-            };
+            snapshot = new Data.Entities.Snapshot {FilterListId = list.Id};
         }
 
-        public async Task SaveAsync()
+        public async Task SaveSnapshotAsync()
         {
             using (var transaction = dbContext.Database.BeginTransaction())
             {
@@ -125,26 +121,26 @@ private async Task SendExceptionEmail(Exception e)
 
         private async Task SaveSnapshotInBatches(string content)
         {
-            var rawRules = ParseRawRules(content);
-            var snapshotBatches = CreateSnapshotBatches(rawRules);
+            var rawRules = GetRawRules(content);
+            var snapshotBatches = GetSnapshotBatches(rawRules);
             await SaveSnapshotBatches(snapshotBatches);
         }
 
-        private static IEnumerable<string> ParseRawRules(string content)
+        private static IEnumerable<string> GetRawRules(string content)
         {
             var rawRules = content.Split(new[] {"\r\n", "\r", "\n"}, StringSplitOptions.RemoveEmptyEntries);
             for (var i = 0; i < rawRules.Length; i++)
                 rawRules[i] = rawRules[i].LintRawRule();
-            return rawRules.Where(r => r != null);
+            return new HashSet<string>(rawRules.Where(r => r != null));
         }
 
-        private IEnumerable<SnapshotDeBatch> CreateSnapshotBatches(IEnumerable<string> rawRules) =>
-            rawRules.Batch(BatchSize).Select(b => new SnapshotDeBatch(dbContext, snapshot, b));
+        private IEnumerable<SnapshotBatchDe> GetSnapshotBatches(IEnumerable<string> rawRules) =>
+            rawRules.GetBatches(BatchSize).Select(b => new SnapshotBatchDe(dbContext, snapshot, b));
 
-        private static async Task SaveSnapshotBatches(IEnumerable<SnapshotDeBatch> snapshotBatches)
+        private static async Task SaveSnapshotBatches(IEnumerable<SnapshotBatchDe> snapshotBatches)
         {
             foreach (var snapshotBatch in snapshotBatches)
-                await snapshotBatch.SaveAsync();
+                await snapshotBatch.SaveSnapshotBatchAsync();
         }
 
         private async Task DedupSnapshotRules()
diff --git a/src/FilterLists.Services/Snapshot/SnapshotService.cs b/src/FilterLists.Services/Snapshot/SnapshotService.cs
index c53959a93..870d8ffe7 100644
--- a/src/FilterLists.Services/Snapshot/SnapshotService.cs
+++ b/src/FilterLists.Services/Snapshot/SnapshotService.cs
@@ -69,7 +69,7 @@ private IEnumerable<SnapshotDe> CreateSnapshots(IEnumerable<FilterListViewUrlDto
         private static async Task SaveSnapshots(IEnumerable<SnapshotDe> snapshots)
         {
             foreach (var snapshot in snapshots)
-                await snapshot.SaveAsync();
+                await snapshot.SaveSnapshotAsync();
         }
     }
 }
\ No newline at end of file