diff --git a/runtime/src/accounts_index.rs b/runtime/src/accounts_index.rs
index 79bdfebec9..7a182537a0 100644
--- a/runtime/src/accounts_index.rs
+++ b/runtime/src/accounts_index.rs
@@ -45,7 +45,7 @@ pub type SlotSlice<'s, T> = &'s [(Slot, T)];
 pub type RefCount = u64;
 pub type AccountMap<V> = InMemAccountsIndex<V>;
 
-type AccountMapEntry<T> = Arc<AccountMapEntryInner<T>>;
+pub(crate) type AccountMapEntry<T> = Arc<AccountMapEntryInner<T>>;
 
 pub trait IsCached: 'static + Clone + Debug + PartialEq + ZeroLamport + Copy + Default {
     fn is_cached(&self) -> bool;
@@ -756,7 +756,7 @@ pub trait ZeroLamport {
     fn is_zero_lamport(&self) -> bool;
 }
 
-type MapType<T> = AccountMap<AccountMapEntry<T>>;
+type MapType<T> = AccountMap<T>;
 type LockMapType<T> = Vec<RwLock<MapType<T>>>;
 type LockMapTypeSlice<T> = [RwLock<MapType<T>>];
 type AccountMapsWriteLock<'a, T> = RwLockWriteGuard<'a, MapType<T>>;
diff --git a/runtime/src/in_mem_accounts_index.rs b/runtime/src/in_mem_accounts_index.rs
index c2d359029f..8227d7c891 100644
--- a/runtime/src/in_mem_accounts_index.rs
+++ b/runtime/src/in_mem_accounts_index.rs
@@ -1,3 +1,4 @@
+use crate::accounts_index::{AccountMapEntry, IsCached};
 use solana_sdk::pubkey::Pubkey;
 use std::collections::{
     hash_map::{Entry, Iter, Keys},
@@ -9,31 +10,31 @@ type K = Pubkey;
 
 // one instance of this represents one bin of the accounts index.
 #[derive(Debug, Default)]
-pub struct InMemAccountsIndex<V> {
+pub struct InMemAccountsIndex<V: IsCached> {
     // backing store
-    map: HashMap<Pubkey, V>,
+    map: HashMap<Pubkey, AccountMapEntry<V>>,
 }
 
-impl<V> InMemAccountsIndex<V> {
+impl<V: IsCached> InMemAccountsIndex<V> {
     pub fn new() -> Self {
         Self {
             map: HashMap::new(),
         }
     }
 
-    pub fn entry(&mut self, pubkey: Pubkey) -> Entry<K, V> {
+    pub fn entry(&mut self, pubkey: Pubkey) -> Entry<K, AccountMapEntry<V>> {
         self.map.entry(pubkey)
     }
 
-    pub fn iter(&self) -> Iter<K, V> {
+    pub fn iter(&self) -> Iter<K, AccountMapEntry<V>> {
         self.map.iter()
     }
 
-    pub fn keys(&self) -> Keys<K, V> {
+    pub fn keys(&self) -> Keys<K, AccountMapEntry<V>> {
         self.map.keys()
     }
 
-    pub fn get(&self, key: &K) -> Option<&V> {
+    pub fn get(&self, key: &K) -> Option<&AccountMapEntry<V>> {
         self.map.get(key)
     }