diff --git a/include/avian/heap/heap.h b/include/avian/heap/heap.h
index e4e5ba929f..53dc343141 100644
--- a/include/avian/heap/heap.h
+++ b/include/avian/heap/heap.h
@@ -58,10 +58,10 @@ class Heap : public avian::util::Allocator {
                        unsigned footprint,
                        int pendingAllocation) = 0;
   virtual unsigned fixedFootprint(unsigned sizeInWords, bool objectMask) = 0;
-  virtual void* allocateFixed(avian::util::Allocator* allocator,
+  virtual void* allocateFixed(avian::util::Alloc* allocator,
                               unsigned sizeInWords,
                               bool objectMask) = 0;
-  virtual void* allocateImmortalFixed(avian::util::Allocator* allocator,
+  virtual void* allocateImmortalFixed(avian::util::Alloc* allocator,
                                       unsigned sizeInWords,
                                       bool objectMask) = 0;
   virtual void mark(void* p, unsigned offset, unsigned count) = 0;
diff --git a/include/avian/system/system.h b/include/avian/system/system.h
index 058d6d1fcd..304112dfe8 100644
--- a/include/avian/system/system.h
+++ b/include/avian/system/system.h
@@ -130,7 +130,7 @@ class System : public avian::util::Aborter {
   virtual Status load(Library**, const char* name) = 0;
   virtual char pathSeparator() = 0;
   virtual char fileSeparator() = 0;
-  virtual const char* toAbsolutePath(avian::util::Allocator* allocator,
+  virtual const char* toAbsolutePath(avian::util::AllocOnly* allocator,
                                      const char* name) = 0;
   virtual int64_t now() = 0;
   virtual void yield() = 0;
diff --git a/include/avian/util/allocator.h b/include/avian/util/allocator.h
index 8b5b1b9232..2e1fe30587 100644
--- a/include/avian/util/allocator.h
+++ b/include/avian/util/allocator.h
@@ -21,10 +21,14 @@ class AllocOnly {
   virtual void* allocate(size_t size) = 0;
 };
 
-class Allocator : public AllocOnly {
+class Alloc : public AllocOnly {
+ public:
+  virtual void free(const void* p, size_t size) = 0;
+};
+
+class Allocator : public Alloc {
  public:
   virtual void* tryAllocate(size_t size) = 0;
-  virtual void free(const void* p, size_t size) = 0;
 };
 
 }  // namespace util
diff --git a/include/avian/util/fixed-allocator.h b/include/avian/util/fixed-allocator.h
index 0d3898bcb1..220bd5b1db 100644
--- a/include/avian/util/fixed-allocator.h
+++ b/include/avian/util/fixed-allocator.h
@@ -20,7 +20,7 @@ namespace util {
 
 // An Allocator that allocates, bump-pointer style, out of a pre-defined chunk
 // of memory.
-class FixedAllocator : public Allocator {
+class FixedAllocator : public Alloc {
  public:
   FixedAllocator(Aborter* a, Slice<uint8_t> memory);
 
diff --git a/src/avian/append.h b/src/avian/append.h
index 22a8854d59..2a0be10151 100644
--- a/src/avian/append.h
+++ b/src/avian/append.h
@@ -16,7 +16,7 @@
 
 namespace vm {
 
-inline const char* append(avian::util::Allocator* allocator,
+inline const char* append(avian::util::AllocOnly* allocator,
                           const char* a,
                           const char* b,
                           const char* c)
@@ -31,7 +31,7 @@ inline const char* append(avian::util::Allocator* allocator,
   return p;
 }
 
-inline const char* append(avian::util::Allocator* allocator,
+inline const char* append(avian::util::AllocOnly* allocator,
                           const char* a,
                           const char* b)
 {
@@ -43,7 +43,7 @@ inline const char* append(avian::util::Allocator* allocator,
   return p;
 }
 
-inline const char* copy(avian::util::Allocator* allocator, const char* a)
+inline const char* copy(avian::util::AllocOnly* allocator, const char* a)
 {
   unsigned al = strlen(a);
   char* p = static_cast<char*>(allocator->allocate(al + 1));
diff --git a/src/avian/finder.h b/src/avian/finder.h
index cb37d2789b..fe0e34e888 100644
--- a/src/avian/finder.h
+++ b/src/avian/finder.h
@@ -16,7 +16,7 @@
 
 namespace avian {
 namespace util {
-class Allocator;
+class Alloc;
 }
 }
 
@@ -202,12 +202,12 @@ class Finder {
 };
 
 AVIAN_EXPORT Finder* makeFinder(System* s,
-                                avian::util::Allocator* a,
+                                avian::util::Alloc* a,
                                 const char* path,
                                 const char* bootLibrary);
 
 Finder* makeFinder(System* s,
-                   avian::util::Allocator* a,
+                   avian::util::Alloc* a,
                    const uint8_t* jarData,
                    unsigned jarLength);
 
diff --git a/src/avian/machine.h b/src/avian/machine.h
index c4ec3360fa..36f65ee868 100644
--- a/src/avian/machine.h
+++ b/src/avian/machine.h
@@ -1596,7 +1596,7 @@ inline bool ensure(Thread* t, unsigned sizeInBytes)
 object allocate2(Thread* t, unsigned sizeInBytes, bool objectMask);
 
 object allocate3(Thread* t,
-                 Allocator* allocator,
+                 Alloc* allocator,
                  Machine::AllocationType type,
                  unsigned sizeInBytes,
                  bool objectMask);
diff --git a/src/compile.cpp b/src/compile.cpp
index ead6942a1e..bd5234db04 100644
--- a/src/compile.cpp
+++ b/src/compile.cpp
@@ -1264,7 +1264,7 @@ class Context {
   TraceElement* traceLog;
   Slice<uint16_t> visitTable;
   Slice<uintptr_t> rootTable;
-  Allocator* executableAllocator;
+  Alloc* executableAllocator;
   void* executableStart;
   unsigned executableSize;
   unsigned objectPoolCount;
diff --git a/src/finder.cpp b/src/finder.cpp
index 28ea5bd14d..59479a2534 100644
--- a/src/finder.cpp
+++ b/src/finder.cpp
@@ -56,7 +56,7 @@ class DirectoryElement : public Element {
  public:
   class Iterator : public Element::Iterator {
    public:
-    Iterator(System* s, Allocator* allocator, const char* name, unsigned skip)
+    Iterator(System* s, Alloc* allocator, const char* name, unsigned skip)
         : s(s),
           allocator(allocator),
           name(name),
@@ -113,7 +113,7 @@ class DirectoryElement : public Element {
     }
 
     System* s;
-    Allocator* allocator;
+    Alloc* allocator;
     const char* name;
     unsigned skip;
     System::Directory* directory;
@@ -121,7 +121,7 @@ class DirectoryElement : public Element {
     Iterator* it;
   };
 
-  DirectoryElement(System* s, Allocator* allocator, const char* name)
+  DirectoryElement(System* s, Alloc* allocator, const char* name)
       : s(s),
         allocator(allocator),
         originalName(name),
@@ -188,7 +188,7 @@ class DirectoryElement : public Element {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   const char* originalName;
   const char* name;
   const char* urlPrefix_;
@@ -198,7 +198,7 @@ class DirectoryElement : public Element {
 class PointerRegion : public System::Region {
  public:
   PointerRegion(System* s,
-                Allocator* allocator,
+                Alloc* allocator,
                 const uint8_t* start,
                 size_t length,
                 bool freePointer = false)
@@ -229,7 +229,7 @@ class PointerRegion : public System::Region {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   const uint8_t* start_;
   size_t length_;
   bool freePointer;
@@ -237,7 +237,7 @@ class PointerRegion : public System::Region {
 
 class DataRegion : public System::Region {
  public:
-  DataRegion(System* s, Allocator* allocator, size_t length)
+  DataRegion(System* s, Alloc* allocator, size_t length)
       : s(s), allocator(allocator), length_(length)
   {
   }
@@ -258,7 +258,7 @@ class DataRegion : public System::Region {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   size_t length_;
   uint8_t data[0];
 };
@@ -277,7 +277,7 @@ class JarIndex {
     const uint8_t* entry;
   };
 
-  JarIndex(System* s, Allocator* allocator, unsigned capacity)
+  JarIndex(System* s, Alloc* allocator, unsigned capacity)
       : s(s),
         allocator(allocator),
         capacity(capacity),
@@ -288,14 +288,14 @@ class JarIndex {
     memset(table, 0, sizeof(List<Entry>*) * capacity);
   }
 
-  static JarIndex* make(System* s, Allocator* allocator, unsigned capacity)
+  static JarIndex* make(System* s, Alloc* allocator, unsigned capacity)
   {
     return new (allocator->allocate(sizeof(JarIndex)
                                     + (sizeof(List<Entry>*) * capacity)))
         JarIndex(s, allocator, capacity);
   }
 
-  static JarIndex* open(System* s, Allocator* allocator, System::Region* region)
+  static JarIndex* open(System* s, Alloc* allocator, System::Region* region)
   {
     JarIndex* index = make(s, allocator, 32);
 
@@ -438,7 +438,7 @@ class JarIndex {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   unsigned capacity;
   unsigned position;
 
@@ -450,7 +450,7 @@ class JarElement : public Element {
  public:
   class Iterator : public Element::Iterator {
    public:
-    Iterator(System* s, Allocator* allocator, JarIndex* index)
+    Iterator(System* s, Alloc* allocator, JarIndex* index)
         : s(s), allocator(allocator), index(index), position(0)
     {
     }
@@ -472,13 +472,13 @@ class JarElement : public Element {
     }
 
     System* s;
-    Allocator* allocator;
+    Alloc* allocator;
     JarIndex* index;
     unsigned position;
   };
 
   JarElement(System* s,
-             Allocator* allocator,
+             Alloc* allocator,
              const char* name,
              bool canonicalizePath = true)
       : s(s),
@@ -495,7 +495,7 @@ class JarElement : public Element {
   }
 
   JarElement(System* s,
-             Allocator* allocator,
+             Alloc* allocator,
              const uint8_t* jarData,
              unsigned jarLength)
       : s(s),
@@ -599,7 +599,7 @@ class JarElement : public Element {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   const char* originalName;
   const char* name;
   const char* urlPrefix_;
@@ -611,7 +611,7 @@ class JarElement : public Element {
 class BuiltinElement : public JarElement {
  public:
   BuiltinElement(System* s,
-                 Allocator* allocator,
+                 Alloc* allocator,
                  const char* name,
                  const char* libraryName)
       : JarElement(s, allocator, name, false),
@@ -711,7 +711,7 @@ unsigned baseName(const char* name, char fileSeparator)
 void add(System* s,
          Element** first,
          Element** last,
-         Allocator* allocator,
+         Alloc* allocator,
          const char* name,
          unsigned nameLength,
          const char* bootLibrary);
@@ -719,7 +719,7 @@ void add(System* s,
 void addTokens(System* s,
                Element** first,
                Element** last,
-               Allocator* allocator,
+               Alloc* allocator,
                const char* jarName,
                unsigned jarNameBase,
                const char* tokens,
@@ -756,7 +756,7 @@ bool continuationLine(const uint8_t* base,
 void addJar(System* s,
             Element** first,
             Element** last,
-            Allocator* allocator,
+            Alloc* allocator,
             const char* name,
             const char* bootLibrary)
 {
@@ -852,7 +852,7 @@ void addJar(System* s,
 void add(System* s,
          Element** first,
          Element** last,
-         Allocator* allocator,
+         Alloc* allocator,
          const char* token,
          unsigned tokenLength,
          const char* bootLibrary)
@@ -904,7 +904,7 @@ void add(System* s,
 }
 
 Element* parsePath(System* s,
-                   Allocator* allocator,
+                   Alloc* allocator,
                    const char* path,
                    const char* bootLibrary)
 {
@@ -921,7 +921,7 @@ Element* parsePath(System* s,
 
 class MyIterator : public Finder::IteratorImp {
  public:
-  MyIterator(System* s, Allocator* allocator, Element* path)
+  MyIterator(System* s, Alloc* allocator, Element* path)
       : s(s),
         allocator(allocator),
         e(path ? path->next : 0),
@@ -956,7 +956,7 @@ class MyIterator : public Finder::IteratorImp {
   }
 
   System* s;
-  Allocator* allocator;
+  Alloc* allocator;
   Element* e;
   Element::Iterator* it;
 };
@@ -964,7 +964,7 @@ class MyIterator : public Finder::IteratorImp {
 class MyFinder : public Finder {
  public:
   MyFinder(System* system,
-           Allocator* allocator,
+           Alloc* allocator,
            const char* path,
            const char* bootLibrary)
       : system(system),
@@ -975,7 +975,7 @@ class MyFinder : public Finder {
   }
 
   MyFinder(System* system,
-           Allocator* allocator,
+           Alloc* allocator,
            const uint8_t* jarData,
            unsigned jarLength)
       : system(system),
@@ -1071,7 +1071,7 @@ class MyFinder : public Finder {
   }
 
   System* system;
-  Allocator* allocator;
+  Alloc* allocator;
   Element* path_;
   const char* pathString;
 };
@@ -1081,7 +1081,7 @@ class MyFinder : public Finder {
 namespace vm {
 
 AVIAN_EXPORT Finder* makeFinder(System* s,
-                                Allocator* a,
+                                Alloc* a,
                                 const char* path,
                                 const char* bootLibrary)
 {
@@ -1089,7 +1089,7 @@ AVIAN_EXPORT Finder* makeFinder(System* s,
 }
 
 Finder* makeFinder(System* s,
-                   Allocator* a,
+                   Alloc* a,
                    const uint8_t* jarData,
                    unsigned jarLength)
 {
diff --git a/src/heap/heap.cpp b/src/heap/heap.cpp
index dfd6eb855a..c4b8ff35a7 100644
--- a/src/heap/heap.cpp
+++ b/src/heap/heap.cpp
@@ -1994,7 +1994,7 @@ class MyHeap : public Heap {
     return Fixie::totalSize(sizeInWords, objectMask);
   }
 
-  void* allocateFixed(Allocator* allocator,
+  void* allocateFixed(Alloc* allocator,
                       unsigned sizeInWords,
                       bool objectMask,
                       Fixie** handle,
@@ -2011,7 +2011,7 @@ class MyHeap : public Heap {
         ->body();
   }
 
-  virtual void* allocateFixed(Allocator* allocator,
+  virtual void* allocateFixed(Alloc* allocator,
                               unsigned sizeInWords,
                               bool objectMask)
   {
@@ -2019,7 +2019,7 @@ class MyHeap : public Heap {
         allocator, sizeInWords, objectMask, &(c.fixies), false);
   }
 
-  virtual void* allocateImmortalFixed(Allocator* allocator,
+  virtual void* allocateImmortalFixed(Alloc* allocator,
                                       unsigned sizeInWords,
                                       bool objectMask)
   {
diff --git a/src/machine.cpp b/src/machine.cpp
index f8e312ebc2..519d7ff01f 100644
--- a/src/machine.cpp
+++ b/src/machine.cpp
@@ -4175,7 +4175,7 @@ object allocate2(Thread* t, unsigned sizeInBytes, bool objectMask)
 }
 
 object allocate3(Thread* t,
-                 Allocator* allocator,
+                 Alloc* allocator,
                  Machine::AllocationType type,
                  unsigned sizeInBytes,
                  bool objectMask)
diff --git a/src/main.cpp b/src/main.cpp
index 4471879ae8..fdfd52d864 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -62,20 +62,15 @@ const char* mainClass(const char* jar)
 
   System* system = makeSystem();
 
-  class MyAllocator : public avian::util::Allocator {
+  class MyAllocator : public avian::util::Alloc {
    public:
     MyAllocator(System* s) : s(s)
     {
     }
 
-    virtual void* tryAllocate(size_t size)
-    {
-      return s->tryAllocate(size);
-    }
-
     virtual void* allocate(size_t size)
     {
-      void* p = tryAllocate(size);
+      void* p = s->tryAllocate(size);
       if (p == 0) {
         abort(s);
       }
diff --git a/src/system/posix.cpp b/src/system/posix.cpp
index cf77851414..9dd2c7c016 100644
--- a/src/system/posix.cpp
+++ b/src/system/posix.cpp
@@ -856,7 +856,7 @@ class MySystem : public System {
     return SO_SUFFIX;
   }
 
-  virtual const char* toAbsolutePath(Allocator* allocator, const char* name)
+  virtual const char* toAbsolutePath(AllocOnly* allocator, const char* name)
   {
     if (name[0] == '/') {
       return copy(allocator, name);
diff --git a/src/system/windows.cpp b/src/system/windows.cpp
index b713da966e..54fa952321 100644
--- a/src/system/windows.cpp
+++ b/src/system/windows.cpp
@@ -893,7 +893,7 @@ class MySystem : public System {
     return SO_SUFFIX;
   }
 
-  virtual const char* toAbsolutePath(avian::util::Allocator* allocator,
+  virtual const char* toAbsolutePath(avian::util::AllocOnly* allocator,
                                      const char* name)
   {
 #if !defined(WINAPI_FAMILY) || WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
diff --git a/src/tools/type-generator/main.cpp b/src/tools/type-generator/main.cpp
index b9bb30c84e..ccb2464650 100644
--- a/src/tools/type-generator/main.cpp
+++ b/src/tools/type-generator/main.cpp
@@ -1630,20 +1630,15 @@ int main(int ac, char** av)
 
   System* system = makeSystem();
 
-  class MyAllocator : public avian::util::Allocator {
+  class MyAllocator : public avian::util::Alloc {
    public:
     MyAllocator(System* s) : s(s)
     {
     }
 
-    virtual void* tryAllocate(size_t size)
-    {
-      return s->tryAllocate(size);
-    }
-
     virtual void* allocate(size_t size)
     {
-      void* p = tryAllocate(size);
+      void* p = s->tryAllocate(size);
       if (p == 0) {
         abort(s);
       }