diff --git a/src/client.rs b/src/client.rs
index a14dce7da..81e2b640f 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -381,7 +381,7 @@ where
                     connected_at,
                 ),
                 HelloResponse { uaid: None, .. } => {
-                    return Err("Already connected elsewhere".into())
+                    return Err("Already connected elsewhere".into());
                 }
             }
         };
@@ -845,8 +845,12 @@ where
             }) => {
                 debug!("Got a register command";
                        "channel_id" => &channel_id_str);
-                let channel_id =
-                    Uuid::parse_str(&channel_id_str).chain_err(|| "Invalid channelID")?;
+                let channel_id = Uuid::parse_str(&channel_id_str).chain_err(|| {
+                    ErrorKind::InvalidClientMessage(format!(
+                        "Invalid channelID: {}",
+                        channel_id_str
+                    ))
+                })?;
                 if channel_id.to_hyphenated().to_string() != channel_id_str {
                     return Err(ErrorKind::InvalidClientMessage(format!(
                         "Invalid UUID format, not lower-case/dashed: {}",
diff --git a/src/db/commands.rs b/src/db/commands.rs
index fabef4460..25e6bdac9 100644
--- a/src/db/commands.rs
+++ b/src/db/commands.rs
@@ -9,9 +9,10 @@ use chrono::Utc;
 use futures::{future, Future};
 use futures_backoff::retry_if;
 use rusoto_dynamodb::{
-    AttributeValue, DeleteItemError, DeleteItemInput, DeleteItemOutput, DynamoDb, GetItemError,
-    GetItemInput, GetItemOutput, ListTablesInput, ListTablesOutput, PutItemError, PutItemInput,
-    PutItemOutput, QueryError, QueryInput, UpdateItemError, UpdateItemInput, UpdateItemOutput,
+    AttributeValue, BatchWriteItemError, DeleteItemError, DeleteItemInput, DeleteItemOutput,
+    DynamoDb, GetItemError, GetItemInput, GetItemOutput, ListTablesInput, ListTablesOutput,
+    PutItemError, PutItemInput, PutItemOutput, QueryError, QueryInput, UpdateItemError,
+    UpdateItemInput, UpdateItemOutput,
 };
 use serde_dynamodb;
 
@@ -24,7 +25,7 @@ use crate::util::timing::sec_since_epoch;
 
 macro_rules! retryable_error {
     ($name:ident, $type:ty, $property:ident) => {
-        fn $name(err: &$type) -> bool {
+        pub fn $name(err: &$type) -> bool {
             match err {
                 $property::InternalServerError(_) | $property::ProvisionedThroughputExceeded(_) => {
                     true
@@ -35,6 +36,11 @@ macro_rules! retryable_error {
     };
 }
 
+retryable_error!(
+    retryable_batchwriteitem_error,
+    BatchWriteItemError,
+    BatchWriteItemError
+);
 retryable_error!(retryable_query_error, QueryError, QueryError);
 retryable_error!(retryable_delete_error, DeleteItemError, DeleteItemError);
 retryable_error!(retryable_getitem_error, GetItemError, GetItemError);
diff --git a/src/db/mod.rs b/src/db/mod.rs
index 7ece7f447..dcfdd3ceb 100644
--- a/src/db/mod.rs
+++ b/src/db/mod.rs
@@ -6,13 +6,11 @@ use uuid::Uuid;
 use cadence::StatsdClient;
 use futures::{future, Future};
 use futures_backoff::retry_if;
-use matches::matches;
 use rusoto_core::{HttpClient, Region};
 use rusoto_credential::StaticProvider;
 use rusoto_dynamodb::{
-    AttributeValue, BatchWriteItemError, BatchWriteItemInput, DeleteItemError, DeleteItemInput,
-    DynamoDb, DynamoDbClient, PutRequest, UpdateItemError, UpdateItemInput, UpdateItemOutput,
-    WriteRequest,
+    AttributeValue, BatchWriteItemInput, DeleteItemInput, DynamoDb, DynamoDbClient, PutRequest,
+    UpdateItemInput, UpdateItemOutput, WriteRequest,
 };
 use serde_dynamodb;
 
@@ -27,7 +25,10 @@ use crate::protocol::Notification;
 use crate::server::{Server, ServerOptions};
 use crate::util::timing::sec_since_epoch;
 
-use self::commands::FetchMessageResponse;
+use self::commands::{
+    retryable_batchwriteitem_error, retryable_delete_error, retryable_updateitem_error,
+    FetchMessageResponse,
+};
 use self::models::{DynamoDbNotification, DynamoDbUser};
 
 const MAX_EXPIRY: u64 = 2_592_000;
@@ -130,9 +131,7 @@ impl DynamoStorage {
 
         retry_if(
             move || ddb.update_item(update_input.clone()),
-            |err: &UpdateItemError| {
-                matches!(err, &UpdateItemError::ProvisionedThroughputExceeded(_))
-            },
+            retryable_updateitem_error,
         )
         .chain_err(|| "Error incrementing storage")
     }
@@ -208,7 +207,7 @@ impl DynamoStorage {
                 return Box::new(future::ok(RegisterResponse::Error {
                     error_msg: "Failed to generate endpoint".to_string(),
                     status: 400,
-                }))
+                }));
             }
         };
         let mut chids = HashSet::new();
@@ -295,9 +294,7 @@ impl DynamoStorage {
 
         retry_if(
             move || ddb.batch_write_item(batch_input.clone()),
-            |err: &BatchWriteItemError| {
-                matches!(err, &BatchWriteItemError::ProvisionedThroughputExceeded(_))
-            },
+            retryable_batchwriteitem_error,
         )
         .and_then(|_| future::ok(()))
         .map_err(|err| {
@@ -331,9 +328,7 @@ impl DynamoStorage {
 
         retry_if(
             move || ddb.delete_item(delete_input.clone()),
-            |err: &DeleteItemError| {
-                matches!(err, &DeleteItemError::ProvisionedThroughputExceeded(_))
-            },
+            retryable_delete_error,
         )
         .and_then(|_| future::ok(()))
         .chain_err(|| "Error deleting notification")
diff --git a/src/server/mod.rs b/src/server/mod.rs
index e45d48f0e..f7a117d04 100644
--- a/src/server/mod.rs
+++ b/src/server/mod.rs
@@ -896,7 +896,9 @@ where
                 }
 
                 Message::Binary(_) => {
-                    return Err(ErrorKind::InvalidClientMessage("binary content".to_string()).into())
+                    return Err(
+                        ErrorKind::InvalidClientMessage("binary content".to_string()).into(),
+                    );
                 }
 
                 // sending a pong is already managed by lower layers, just go to