diff --git a/GlassVPN/PacketTunnelProvider.swift b/GlassVPN/PacketTunnelProvider.swift
index b584ee8..e8288c3 100644
--- a/GlassVPN/PacketTunnelProvider.swift
+++ b/GlassVPN/PacketTunnelProvider.swift
@@ -1,7 +1,5 @@
 import NetworkExtension
 
-fileprivate var db: SQLiteDatabase!
-fileprivate var pStmt: OpaquePointer!
 fileprivate var filterDomains: [String]!
 fileprivate var filterOptions: [(block: Bool, ignore: Bool)]!
 
@@ -9,7 +7,7 @@ fileprivate var filterOptions: [(block: Bool, ignore: Bool)]!
 // MARK: Backward DNS Binary Tree Lookup
 
 fileprivate func reloadDomainFilter() {
-	let tmp = db.loadFilters()?.map({
+	let tmp = AppDB?.loadFilters()?.map({
 		(String($0.reversed()), $1)
 	}).sorted(by: { $0.0 < $1.0 }) ?? []
 	filterDomains = tmp.map { $0.0 }
@@ -35,6 +33,18 @@ fileprivate func filterIndex(for domain: String) -> Int {
 	return -1
 }
 
+private let queue = DispatchQueue.init(label: "PSIGlassDNSQueue", qos: .userInteractive, target: .main)
+
+private func logAsync(_ domain: String, blocked: Bool) {
+	queue.async {
+		do {
+			try AppDB?.logWrite(domain, blocked: blocked)
+		} catch {
+			DDLogWarn("Couldn't write: \(error)")
+		}
+	}
+}
+
 
 // MARK: ObserverFactory
 
@@ -52,11 +62,11 @@ class LDObserverFactory: ObserverFactory {
 				let i = filterIndex(for: session.host)
 				if i >= 0 {
 					let (block, ignore) = filterOptions[i]
-					if !ignore { try? db.logWrite(pStmt, session.host, blocked: block) }
+					if !ignore { logAsync(session.host, blocked: block) }
 					if block { socket.forceDisconnect() }
 				} else {
 					// TODO: disable filter during recordings
-					try? db.logWrite(pStmt, session.host)
+					logAsync(session.host, blocked: false)
 				}
 			default:
 				break
@@ -76,9 +86,7 @@ class PacketTunnelProvider: NEPacketTunnelProvider {
 	
 	override func startTunnel(options: [String : NSObject]?, completionHandler: @escaping (Error?) -> Void) {
 		do {
-			db = try SQLiteDatabase.open()
-			db.initCommonScheme()
-			pStmt = try db.logWritePrepare()
+			try SQLiteDatabase.open().initCommonScheme()
 		} catch {
 			completionHandler(error)
 			return
@@ -135,9 +143,6 @@ class PacketTunnelProvider: NEPacketTunnelProvider {
 		ObserverFactory.currentFactory = nil
 		proxyServer.stop()
 		proxyServer = nil
-		db.prepared(finalize: pStmt)
-		pStmt = nil
-		db = nil
 		filterDomains = nil
 		filterOptions = nil
 		completionHandler()
diff --git a/main/DB/DBCommon.swift b/main/DB/DBCommon.swift
index 38e939a..0bb9244 100644
--- a/main/DB/DBCommon.swift
+++ b/main/DB/DBCommon.swift
@@ -25,16 +25,22 @@ extension CreateTable {
 }
 
 extension SQLiteDatabase {
+//	/// `INSERT INTO cache (dns, opt) VALUES (?, ?);`
+//	func logWritePrepare() throws -> OpaquePointer {
+//		try prepare(sql: "INSERT INTO cache (dns, opt) VALUES (?, ?);")
+//	}
+//	/// `prep` must exist and be initialized with `logWritePrepare()`
+//	func logWrite(_ pStmt: OpaquePointer!, _ domain: String, blocked: Bool = false) throws {
+//		guard let prep = pStmt else {
+//			return
+//		}
+//		try prepared(run: prep, bind: [BindText(domain), BindInt32(blocked ? 1 : 0)])
+//	}
 	/// `INSERT INTO cache (dns, opt) VALUES (?, ?);`
-	func logWritePrepare() throws -> OpaquePointer {
-		try prepare(sql: "INSERT INTO cache (dns, opt) VALUES (?, ?);")
-	}
-	/// `prep` must exist and be initialized with `logWritePrepare()`
-	func logWrite(_ pStmt: OpaquePointer!, _ domain: String, blocked: Bool = false) throws {
-		guard let prep = pStmt else {
-			return
-		}
-		try prepared(run: prep, bind: [BindText(domain), BindInt32(blocked ? 1 : 0)])
+	func logWrite(_ domain: String, blocked: Bool = false) throws {
+		try self.run(sql: "INSERT INTO cache (dns, opt) VALUES (?, ?);",
+			bind: [BindText(domain), BindInt32(blocked ? 1 : 0)])
+		{ try ifStep($0, SQLITE_DONE) }
 	}
 }
 
@@ -52,10 +58,10 @@ extension CreateTable {
 }
 
 struct FilterOptions: OptionSet {
-    let rawValue: Int32
+	let rawValue: Int32
 	static let none    = FilterOptions([])
-    static let blocked = FilterOptions(rawValue: 1 << 0)
-    static let ignored = FilterOptions(rawValue: 1 << 1)
+	static let blocked = FilterOptions(rawValue: 1 << 0)
+	static let ignored = FilterOptions(rawValue: 1 << 1)
 	static let any     = FilterOptions(rawValue: 0b11)
 }
 
diff --git a/main/DB/DBCore.swift b/main/DB/DBCore.swift
index a4ad215..8332033 100644
--- a/main/DB/DBCore.swift
+++ b/main/DB/DBCore.swift
@@ -35,7 +35,7 @@ class SQLiteDatabase {
 	}
 	
 	deinit {
-		sqlite3_close(dbPointer)
+		sqlite3_close_v2(dbPointer)
 	}
 	
 	static func destroyDatabase(path: String = URL.internalDB().relativePath) {
@@ -47,15 +47,10 @@ class SQLiteDatabase {
 	
 	static func open(path: String = URL.internalDB().relativePath) throws -> SQLiteDatabase {
 		var db: OpaquePointer?
-		//sqlite3_open_v2(path, &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_SHAREDCACHE, nil)
-		if sqlite3_open(path, &db) == SQLITE_OK {
+		if sqlite3_open_v2(path, &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE | SQLITE_OPEN_FULLMUTEX, nil) == SQLITE_OK {
 			return SQLiteDatabase(dbPointer: db)
 		} else {
-			defer {
-				if db != nil {
-					sqlite3_close(db)
-				}
-			}
+			defer { sqlite3_close_v2(db) }
 			if let errorPointer = sqlite3_errmsg(db) {
 				let message = String(cString: errorPointer)
 				throw SQLiteError.OpenDatabase(message: message)
@@ -222,6 +217,7 @@ extension SQLiteDatabase {
 	func prepare(sql: String) throws -> OpaquePointer {
 		var pStmt: OpaquePointer?
 		guard sqlite3_prepare_v2(dbPointer, sql, -1, &pStmt, nil) == SQLITE_OK, let S = pStmt else {
+			sqlite3_finalize(pStmt)
 			throw SQLiteError.Prepare(message: errorMessage)
 		}
 		return S
diff --git a/main/Data Source/TestDataSource.swift b/main/Data Source/TestDataSource.swift
index bcfd84f..cf2f6b4 100644
--- a/main/Data Source/TestDataSource.swift	
+++ b/main/Data Source/TestDataSource.swift	
@@ -2,25 +2,22 @@ import Foundation
 
 #if IOS_SIMULATOR
 
-private let db = AppDB!
-private var pStmt: OpaquePointer?
-
 class TestDataSource {
 	
 	static func load() {
 		QLog.Debug("SQLite path: \(URL.internalDB())")
 		
+		let db = AppDB!
 		let deleted = db.dnsLogsDelete("test.com", strict: false)
 		try? db.run(sql: "DELETE FROM cache;")
 		QLog.Debug("Deleting \(deleted) rows matching 'test.com' (+ \(db.numberOfChanges) in cache)")
 		
 		QLog.Debug("Writing 33 test logs")
-		pStmt = try! db.logWritePrepare()
-		try? db.logWrite(pStmt, "keeptest.com", blocked: false)
-		for _ in 1...4 { try? db.logWrite(pStmt, "test.com", blocked: false) }
-		for _ in 1...7 { try? db.logWrite(pStmt, "i.test.com", blocked: false) }
-		for i in 1...8 { try? db.logWrite(pStmt, "b.test.com", blocked: i>5) }
-		for i in 1...13 { try? db.logWrite(pStmt, "bi.test.com", blocked: i%2==0) }
+		try? db.logWrite("keeptest.com", blocked: false)
+		for _ in 1...4 { try? db.logWrite("test.com", blocked: false) }
+		for _ in 1...7 { try? db.logWrite("i.test.com", blocked: false) }
+		for i in 1...8 { try? db.logWrite("b.test.com", blocked: i>5) }
+		for i in 1...13 { try? db.logWrite("bi.test.com", blocked: i%2==0) }
 		
 		db.dnsLogsPersist()
 		
@@ -36,7 +33,7 @@ class TestDataSource {
 	
 	@objc static func insertRandom() {
 		//QLog.Debug("Inserting 1 periodic log entry")
-		try? db.logWrite(pStmt, "\(arc4random() % 5).count.test.com", blocked: true)
+		try? AppDB?.logWrite("\(arc4random() % 5).count.test.com", blocked: true)
 	}
 }
 #endif