diff --git a/contracts/FlowtyRaffles.cdc b/contracts/FlowtyRaffles.cdc
index a94dbc3..3cc978c 100644
--- a/contracts/FlowtyRaffles.cdc
+++ b/contracts/FlowtyRaffles.cdc
@@ -1,6 +1,6 @@
 import "MetadataViews"
 import "RandomBeaconHistory"
-// import "Xorshift128plus"
+import "Xorshift128plus"
 
 pub contract FlowtyRaffles {
     pub let ManagerStoragePath: StoragePath
@@ -343,22 +343,20 @@ pub contract FlowtyRaffles {
     // taken from
     // https://github.com/onflow/random-coin-toss/blob/4271cd571b7761af36b0f1037767171aeca18387/contracts/CoinToss.cdc#L95
     pub fun randUInt64(atBlockHeight: UInt64, salt: UInt64): UInt64 {
-        // // query the Random Beacon history core-contract - if `blockHeight` <= current block height, panic & revert
-        // let sourceOfRandomness = RandomBeaconHistory.sourceOfRandomness(atBlockHeight: atBlockHeight)
-        // assert(sourceOfRandomness.blockHeight == atBlockHeight, message: "RandomSource block height mismatch")
-
-        // // instantiate a PRG object, seeding a source of randomness with `salt` and returns a pseudo-random
-        // // generator object.
-        // let prg = Xorshift128plus.PRG(
-        //     sourceOfRandomness: sourceOfRandomness.value,
-        //     salt: salt.toBigEndianBytes()
-        // )
-
-        // return prg.nextUInt64()
-        // TODO: use commented-out implementation once we can test using the randomness beacon in the cadence testing framework
-        return revertibleRandom()
+        // query the Random Beacon history core-contract - if `blockHeight` <= current block height, panic & revert
+        let sourceOfRandomness = RandomBeaconHistory.sourceOfRandomnessAtBlockHeight(blockHeight: atBlockHeight)
+        assert(sourceOfRandomness.blockHeight == atBlockHeight, message: "RandomSource block height mismatch")
+
+        // instantiate a PRG object, seeding a source of randomness with `salt` and returns a pseudo-random
+        // generator object.
+        let prg = Xorshift128plus.PRG(
+            sourceOfRandomness: sourceOfRandomness.value,
+            salt: salt.toBigEndianBytes()
+        )
+
+        return prg.nextUInt64()
     }
-
+ 
     pub fun extractString(_ value: AnyStruct?): String? {
         if value == nil {
             return nil
diff --git a/contracts/standard/RandomBeaconHistory.cdc b/contracts/standard/RandomBeaconHistory.cdc
index 28d20ab..de2d272 100644
--- a/contracts/standard/RandomBeaconHistory.cdc
+++ b/contracts/standard/RandomBeaconHistory.cdc
@@ -85,22 +85,22 @@ access(all) contract RandomBeaconHistory {
     /// precedes or exceeds the recorded history. Note that a source of randomness for block n will not be accessible
     /// until block n+1.
     ///
-    /// @param atBlockHeight The block height at which to retrieve the source of randomness
+    /// @param blockHeight The block height at which to retrieve the source of randomness
     ///
     /// @return The source of randomness at the given block height as RandomSource struct
     ///
-    access(all) fun sourceOfRandomness(atBlockHeight: UInt64): RandomSource {
+    access(all) fun sourceOfRandomnessAtBlockHeight(blockHeight: UInt64): RandomSource {
         pre {
             self.lowestHeight != nil: "History has not yet been initialized"
-            atBlockHeight >= self.lowestHeight!: "Requested block height precedes recorded history"
-            atBlockHeight < getCurrentBlock().height: "Source of randomness not yet recorded"
+            blockHeight >= self.lowestHeight!: "Requested block height precedes recorded history"
+            blockHeight < getCurrentBlock().height: "Source of randomness not yet recorded"
         }
-        let index: UInt64 = atBlockHeight - self.lowestHeight!
+        let index = blockHeight - self.lowestHeight!
         assert(
             index >= 0 && index < UInt64(self.randomSourceHistory.length),
             message: "Problem finding random source history index"
         )
-        return RandomSource(blockHeight: atBlockHeight, value: self.randomSourceHistory[index])
+        return RandomSource(blockHeight: blockHeight, value: self.randomSourceHistory[index])
     }
 
     /// Retrieves a page from the history of random sources, ordered chronologically
@@ -111,7 +111,7 @@ access(all) contract RandomBeaconHistory {
     /// @return A RandomSourceHistoryPage containing RandomSource values in choronological order according to
     /// associated block height
     ///
-    access(all) view fun getRandomSourceHistoryPage(page: UInt64, perPage: UInt64): RandomSourceHistoryPage {
+    access(all) view fun getRandomSourceHistoryPage(_ page: UInt64, perPage: UInt64): RandomSourceHistoryPage {
         pre {
             self.lowestHeight != nil: "History has not yet been initialized"
         }
@@ -132,10 +132,11 @@ access(all) contract RandomBeaconHistory {
         }
 
         // Iterate over history and construct page RandomSource values
+        let lowestHeight = self.lowestHeight!
         for i, block in self.randomSourceHistory.slice(from: Int(startIndex), upTo: Int(endIndex)) {
             values.append(
                 RandomSource(
-                    blockHeight: self.lowestHeight! + startIndex + UInt64(i),
+                    blockHeight: lowestHeight + startIndex + UInt64(i),
                     value: self.randomSourceHistory[startIndex + UInt64(i)]
                 )
             )
diff --git a/test/FlowtyRaffles_tests.cdc b/test/FlowtyRaffles_tests.cdc
index d743019..79962ec 100644
--- a/test/FlowtyRaffles_tests.cdc
+++ b/test/FlowtyRaffles_tests.cdc
@@ -12,14 +12,15 @@ pub let Xorshift128plusContractAddress = Address(0x0000000000000008)
 pub let GenericRaffleSourceIdentifier = "A.0000000000000008.FlowtyRaffleSource.AnyStructRaffleSource"
 
 pub fun setup() {
-    var err = Test.deployContract(name: "FlowtyRaffles", path: "../contracts/FlowtyRaffles.cdc", arguments: [])
+    var err = Test.deployContract(name: "Xorshift128plus", path: "../contracts/standard/Xorshift128plus.cdc", arguments: [])
+    Test.expect(err, Test.beNil())
+
+    err = Test.deployContract(name: "FlowtyRaffles", path: "../contracts/FlowtyRaffles.cdc", arguments: [])
     Test.expect(err, Test.beNil())
 
     err = Test.deployContract(name: "FlowtyRaffleSource", path: "../contracts/FlowtyRaffleSource.cdc", arguments: [])
     Test.expect(err, Test.beNil())
 
-    // err = Test.deployContract(name: "Xorshift128plus", path: "../contracts/standard/Xorshift128plus.cdc", arguments: [])
-    // Test.expect(err, Test.beNil())
 }
 
 pub fun testSetupManager() {