diff --git a/python_tests/memo_test_types.py b/python_tests/memo_test_types.py
index 770d03f4..7769e3fa 100644
--- a/python_tests/memo_test_types.py
+++ b/python_tests/memo_test_types.py
@@ -1,3 +1,4 @@
+from dataclasses import dataclass
 import dbzero as db0
 from datetime import datetime
 
@@ -220,3 +221,13 @@ def __init__(self, type, processor_type, data = None, key = None, parent = None,
         self.child_tasks = []
         self.requirements = requirements        
         self.max_retry = None
+
+
+RANDOM_BYTES = b'DB0'*100000
+
+@db0.memo(no_default_tags=True)
+@dataclass
+class MemoBlob:
+    def __init__(self, size_bytes: int):
+        assert size_bytes <= len(RANDOM_BYTES)
+        self.data = RANDOM_BYTES[:size_bytes]
diff --git a/python_tests/test_issues_11.py b/python_tests/test_issues_11.py
new file mode 100644
index 00000000..ea67633c
--- /dev/null
+++ b/python_tests/test_issues_11.py
@@ -0,0 +1,25 @@
+import dbzero as db0
+import pytest
+from .conftest import DB0_DIR
+from datetime import datetime
+from .memo_test_types import MemoBlob
+import random
+
+
+@pytest.mark.stress_test
+@pytest.mark.parametrize("db0_slab_size", [{"slab_size": 64 << 20, "autocommit": False}], indirect=True)
+def test_wide_lock_badaddr_issue(db0_slab_size):
+    db0.set_cache_size(8 << 30)
+    all_blobs = db0.list()
+    append_count = 300289
+    # append large blobs to force wide locks
+    for count in range(append_count):
+        all_blobs.append(MemoBlob(24 << 10))
+        if count % 50000 == 0:
+            print("Commit...")
+            db0.commit()
+            print(f"Appended {count} blobs")
+    
+    # faulty operation
+    all_blobs.append(MemoBlob(24 << 10))
+            
\ No newline at end of file
diff --git a/src/dbzero/core/collections/SGB_Tree/SGB_CompressedLookupTree.hpp b/src/dbzero/core/collections/SGB_Tree/SGB_CompressedLookupTree.hpp
index 5feea5cc..8f487c55 100644
--- a/src/dbzero/core/collections/SGB_Tree/SGB_CompressedLookupTree.hpp
+++ b/src/dbzero/core/collections/SGB_Tree/SGB_CompressedLookupTree.hpp
@@ -144,7 +144,7 @@ DB0_PACKED_END
         typename ItemEqualType,
         typename CompressedItemEqualType,
         typename CapacityType = std::uint16_t, 
-        typename AddressType = std::uint32_t, 
+        typename AddressType = std::uint64_t,
         typename HeaderType = db0::o_null,
         typename TreeHeaderType = db0::o_null>
     class sgb_compressed_lookup_types
diff --git a/src/dbzero/core/collections/SGB_Tree/SGB_LookupTree.hpp b/src/dbzero/core/collections/SGB_Tree/SGB_LookupTree.hpp
index 4c3e4aaf..11734316 100644
--- a/src/dbzero/core/collections/SGB_Tree/SGB_LookupTree.hpp
+++ b/src/dbzero/core/collections/SGB_Tree/SGB_LookupTree.hpp
@@ -333,7 +333,7 @@ DB0_PACKED_END
         typename ItemCompType, 
         typename ItemEqualType,
         typename CapacityType = std::uint16_t, 
-        typename AddressType = std::uint32_t, 
+        typename AddressType = std::uint64_t,
         typename HeaderType = db0::o_null,
         typename TreeHeaderType = db0::o_null>
     class sgb_lookup_types
diff --git a/src/dbzero/core/collections/SGB_Tree/SGB_Tree.hpp b/src/dbzero/core/collections/SGB_Tree/SGB_Tree.hpp
index 70049dc3..012796f1 100644
--- a/src/dbzero/core/collections/SGB_Tree/SGB_Tree.hpp
+++ b/src/dbzero/core/collections/SGB_Tree/SGB_Tree.hpp
@@ -581,7 +581,7 @@ namespace db0
      * @tparam HeaderT optional fixed-size header to be associated with each node / block (default is none / null), helpful when implementing extensions
     */
     template <typename ItemT, typename ItemCompT = std::less<ItemT>, typename ItemEqualT = std::equal_to<ItemT>,
-        typename CapacityT = std::uint16_t, typename AddressT = std::uint32_t, typename HeaderT = o_null, typename TreeHeaderT = o_null>
+        typename CapacityT = std::uint16_t, typename AddressT = std::uint64_t, typename HeaderT = o_null, typename TreeHeaderT = o_null>
     class SGB_Tree: public SGB_TreeBase<sgb_types<ItemT, ItemCompT, ItemEqualT, CapacityT, AddressT, HeaderT, TreeHeaderT> >
     {
         using super_t = SGB_TreeBase<sgb_types<ItemT, ItemCompT, ItemEqualT, CapacityT, AddressT, HeaderT, TreeHeaderT> >;        
diff --git a/src/dbzero/core/memory/AlgoAllocator.cpp b/src/dbzero/core/memory/AlgoAllocator.cpp
index b7f6d2b3..b651c585 100644
--- a/src/dbzero/core/memory/AlgoAllocator.cpp
+++ b/src/dbzero/core/memory/AlgoAllocator.cpp
@@ -13,11 +13,11 @@ namespace db0
     {
     }
     
-    std::optional<Address> AlgoAllocator::tryAlloc(std::size_t size, std::uint32_t slot_num, 
+    std::optional<Address> AlgoAllocator::tryAlloc(std::size_t size, std::uint32_t slot_num,
         bool aligned, unsigned char)
     {
         assert(slot_num == 0);
-        assert(!aligned && "AlgoAllocator: aligned allocation not supported");    
+        assert(!aligned && "AlgoAllocator: aligned allocation not supported");
         assert(size == m_alloc_size && "AlgoAllocator: invalid alloc size requested");
         return m_address_pool_f(m_next_i++);
     }
@@ -63,7 +63,7 @@ namespace db0
     void AlgoAllocator::reset() {
         m_next_i = 0;
     }
-
+    
     Address AlgoAllocator::getRootAddress() const {
         return m_address_pool_f(0);
     }
diff --git a/src/dbzero/core/memory/MetaAllocator.cpp b/src/dbzero/core/memory/MetaAllocator.cpp
index 9b7482cc..9996c23e 100644
--- a/src/dbzero/core/memory/MetaAllocator.cpp
+++ b/src/dbzero/core/memory/MetaAllocator.cpp
@@ -753,7 +753,7 @@ namespace db0
     
     void MetaAllocator::formatPrefix(std::shared_ptr<Prefix> prefix, std::size_t page_size, std::size_t slab_size)
     {
-        // create the meta-header and the address 0x0
+        // create the meta-header at the address 0x0
         OneShotAllocator one_shot(Address::fromOffset(0), o_meta_header::sizeOf());
         Memspace memspace(Memspace::tag_from_reference(), prefix, one_shot);
         v_object<o_meta_header> meta_header(memspace, page_size, slab_size);