diff --git a/Makefile b/Makefile
index 1d8342b..40d2495 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,5 @@
 CC=gcc
-#CFLAGS=-Wall -pedantic -g -DUNIX_HOST
-CFLAGS=-Wall -pedantic -g -DSRV1_UNIX_HOST
+CFLAGS=-Wall -pedantic -g -DUNIX_HOST
 LIBS=-lm
 
 TARGET	= picoc
diff --git a/include.c b/include.c
index 42f83cd..68e763d 100644
--- a/include.c
+++ b/include.c
@@ -9,28 +9,46 @@ struct IncludeLibrary
     void (*SetupFunction)(void);
     struct LibraryFunction (*FuncList)[];
     const char *SetupCSource;
+    struct IncludeLibrary *NextLib;
 };
 
-struct IncludeLibrary IncludeLibInfo[] =
+struct IncludeLibrary *IncludeLibList = NULL;
+
+
+/* initialise the built-in include libraries */
+void IncludeInit()
 {
-    { "stdio.h", 
-        &StdioSetupFunc, 
-        &StdioFunctions, 
-        StdioDefs },
-    { "math.h", 
-        &MathSetupFunc, 
-        &MathFunctions, 
-        NULL },
-    { "string.h", 
-        &StringSetupFunc, 
-        &StringFunctions, 
-        NULL },
-    { "stdlib.h", 
-        &StdlibSetupFunc, 
-        &StdlibFunctions, 
-        NULL },
-    { NULL, NULL, NULL, NULL }
-};
+    IncludeRegister("stdio.h", &StdioSetupFunc, &StdioFunctions, StdioDefs);
+    IncludeRegister("math.h", &MathSetupFunc, &MathFunctions, NULL);
+    IncludeRegister("string.h", &StringSetupFunc, &StringFunctions, NULL);
+    IncludeRegister("stdlib.h", &StdlibSetupFunc, &StdlibFunctions, NULL);
+}
+
+/* clean up space used by the include system */
+void IncludeCleanup()
+{
+    struct IncludeLibrary *ThisInclude = IncludeLibList;
+    struct IncludeLibrary *NextInclude;
+    
+    while (ThisInclude != NULL)
+    {
+        NextInclude = ThisInclude->NextLib;
+        HeapFreeMem(ThisInclude);
+        ThisInclude = NextInclude;
+    }
+}
+
+/* register a new build-in include file */
+void IncludeRegister(const char *IncludeName, void (*SetupFunction)(void), struct LibraryFunction (*FuncList)[], const char *SetupCSource)
+{
+    struct IncludeLibrary *NewLib = HeapAllocMem(sizeof(struct IncludeLibrary));
+    NewLib->IncludeName = TableStrRegister(IncludeName);
+    NewLib->SetupFunction = SetupFunction;
+    NewLib->FuncList = FuncList;
+    NewLib->SetupCSource = SetupCSource;
+    NewLib->NextLib = IncludeLibList;
+    IncludeLibList = NewLib;
+}
 
 
 /* include one of a number of predefined libraries, or perhaps an actual file */
@@ -39,7 +57,7 @@ void IncludeFile(char *FileName)
     struct IncludeLibrary *LInclude;
     
     /* scan for the include file name to see if it's in our list of predefined includes */
-    for (LInclude = &IncludeLibInfo[0]; LInclude->IncludeName != NULL; LInclude++)
+    for (LInclude = IncludeLibList; LInclude != NULL; LInclude = LInclude->NextLib)
     {
         if (strcmp(LInclude->IncludeName, FileName) == 0)
         {
diff --git a/picoc.c b/picoc.c
index 07d6027..b71198d 100644
--- a/picoc.c
+++ b/picoc.c
@@ -9,18 +9,19 @@ void Initialise()
     VariableInit();
     LexInit();
     TypeInit();
+    IncludeInit();
 #ifdef BUILTIN_MINI_STDLIB
     LibraryInit(&GlobalTable, "c library", &CLibrary);
     CLibraryInit();
 #endif
     PlatformLibraryInit();
-    LibraryInit(&GlobalTable, "platform library", &PlatformLibrary);
 }
 
 /* free memory */
 void Cleanup()
 {
     PlatformCleanup();
+    IncludeCleanup();
     ParseCleanup();
     LexCleanup();
     VariableCleanup();
diff --git a/picoc.h b/picoc.h
index cabeba8..0d6b90e 100644
--- a/picoc.h
+++ b/picoc.h
@@ -291,7 +291,6 @@ extern struct ValueType *VoidPtrType;
 extern char *StrEmpty;
 extern struct PointerValue NULLPointer;
 extern struct LibraryFunction CLibrary[];
-extern struct LibraryFunction PlatformLibrary[];
 extern IOFILE *CStdOut;
 
 /* table.c */
@@ -410,6 +409,9 @@ void Initialise();
 void Cleanup();
 
 /* include.c */
+void IncludeInit();
+void IncludeCleanup();
+void IncludeRegister(const char *IncludeName, void (*SetupFunction)(void), struct LibraryFunction (*FuncList)[], const char *SetupCSource);
 void IncludeFile(char *Filename);
 
 /* stdio.c */
diff --git a/platform/library_ffox.c b/platform/library_ffox.c
index 0b39f55..15465a9 100644
--- a/platform/library_ffox.c
+++ b/platform/library_ffox.c
@@ -1,12 +1,13 @@
 #include "../picoc.h"
 
-void PlatformLibraryInit()
-{
-}
-
 /* list of all library functions and their prototypes */
 struct LibraryFunction PlatformLibrary[] =
 {
     { NULL,         NULL }
 };
 
+void PlatformLibraryInit()
+{
+    LibraryInit(&GlobalTable, "platform library", &PlatformLibrary);
+}
+
diff --git a/platform/library_srv1.c b/platform/library_srv1.c
index 3cfd42b..6b6f7ed 100644
--- a/platform/library_srv1.c
+++ b/platform/library_srv1.c
@@ -4,10 +4,11 @@ static int Blobcnt, Blobx1, Blobx2, Bloby1, Bloby2, Iy1, Iy2, Iu1, Iu2, Iv1, Iv2
 static int GPSlat, GPSlon, GPSalt, GPSfix, GPSsat, GPSutc, Elcount, Ercount;
 static int ScanVect[16], NNVect[NUM_OUTPUT];
 
-void PlatformLibraryInit()
-{
-    struct ValueType *IntArrayType;
-    
+struct ValueType *IntArrayType;
+ 
+
+void SRV1SetupFunc()
+{    
     IntArrayType = TypeGetMatching(NULL, &IntType, TypeArray, 16, StrEmpty);
     VariableDefinePlatformVar(NULL, "scanvect", IntArrayType, (union AnyValue *)&ScanVect, FALSE);
     VariableDefinePlatformVar(NULL, "neuron", IntArrayType, (union AnyValue *)&NNVect, FALSE);
@@ -733,8 +734,14 @@ void Cerrormsg (struct ParseState *Parser, struct Value *ReturnValue, struct Val
     LibPrintf(Parser, ReturnValue, Param, NumArgs);
 }
 
-/* list of all library functions and their prototypes */
+/* nothing here because we don't add any functions until srv1.h is #included */
 struct LibraryFunction PlatformLibrary[] =
+{
+    { NULL,         NULL }
+};
+
+/* list of all library functions included with srv1.h */
+struct LibraryFunction SRV1Functions[] =
 {
     { Csignal,      "int signal();" },
     { Cinput,       "int input();" },
@@ -796,3 +803,7 @@ struct LibraryFunction PlatformLibrary[] =
     { NULL,         NULL }
 };
 
+void PlatformLibraryInit()
+{
+    IncludeRegister("srv1.h", &SRV1SetupFunc, &SRV1Functions, NULL);
+}
diff --git a/platform/library_surveyor.c b/platform/library_surveyor.c
index 3cfd42b..3eb273a 100644
--- a/platform/library_surveyor.c
+++ b/platform/library_surveyor.c
@@ -4,34 +4,6 @@ static int Blobcnt, Blobx1, Blobx2, Bloby1, Bloby2, Iy1, Iy2, Iu1, Iu2, Iv1, Iv2
 static int GPSlat, GPSlon, GPSalt, GPSfix, GPSsat, GPSutc, Elcount, Ercount;
 static int ScanVect[16], NNVect[NUM_OUTPUT];
 
-void PlatformLibraryInit()
-{
-    struct ValueType *IntArrayType;
-    
-    IntArrayType = TypeGetMatching(NULL, &IntType, TypeArray, 16, StrEmpty);
-    VariableDefinePlatformVar(NULL, "scanvect", IntArrayType, (union AnyValue *)&ScanVect, FALSE);
-    VariableDefinePlatformVar(NULL, "neuron", IntArrayType, (union AnyValue *)&NNVect, FALSE);
-    VariableDefinePlatformVar(NULL, "blobcnt", &IntType, (union AnyValue *)&Blobcnt, FALSE);
-    VariableDefinePlatformVar(NULL, "blobx1", &IntType, (union AnyValue *)&Blobx1, FALSE);
-    VariableDefinePlatformVar(NULL, "blobx2", &IntType, (union AnyValue *)&Blobx2, FALSE);
-    VariableDefinePlatformVar(NULL, "bloby1", &IntType, (union AnyValue *)&Bloby1, FALSE);
-    VariableDefinePlatformVar(NULL, "bloby2", &IntType, (union AnyValue *)&Bloby2, FALSE);
-    VariableDefinePlatformVar(NULL, "lcount", &IntType, (union AnyValue *)&Elcount, FALSE);
-    VariableDefinePlatformVar(NULL, "rcount", &IntType, (union AnyValue *)&Ercount, FALSE);
-    VariableDefinePlatformVar(NULL, "y1", &IntType, (union AnyValue *)&Iy1, FALSE);
-    VariableDefinePlatformVar(NULL, "y2", &IntType, (union AnyValue *)&Iy2, FALSE);
-    VariableDefinePlatformVar(NULL, "u1", &IntType, (union AnyValue *)&Iu1, FALSE);
-    VariableDefinePlatformVar(NULL, "u2", &IntType, (union AnyValue *)&Iu2, FALSE);
-    VariableDefinePlatformVar(NULL, "v1", &IntType, (union AnyValue *)&Iv1, FALSE);
-    VariableDefinePlatformVar(NULL, "v2", &IntType, (union AnyValue *)&Iv2, FALSE);
-    VariableDefinePlatformVar(NULL, "gpslat", &IntType, (union AnyValue *)&GPSlat, FALSE);
-    VariableDefinePlatformVar(NULL, "gpslon", &IntType, (union AnyValue *)&GPSlon, FALSE);
-    VariableDefinePlatformVar(NULL, "gpsalt", &IntType, (union AnyValue *)&GPSalt, FALSE);
-    VariableDefinePlatformVar(NULL, "gpsfix", &IntType, (union AnyValue *)&GPSfix, FALSE);
-    VariableDefinePlatformVar(NULL, "gpssat", &IntType, (union AnyValue *)&GPSsat, FALSE);
-    VariableDefinePlatformVar(NULL, "gpsutc", &IntType, (union AnyValue *)&GPSutc, FALSE);
-}
-
 void Csignal(struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs)  // check for kbhit, return t or nil
 {
     if (getsignal())
@@ -796,3 +768,33 @@ struct LibraryFunction PlatformLibrary[] =
     { NULL,         NULL }
 };
 
+void PlatformLibraryInit()
+{
+    struct ValueType *IntArrayType;
+    
+    IntArrayType = TypeGetMatching(NULL, &IntType, TypeArray, 16, StrEmpty);
+    VariableDefinePlatformVar(NULL, "scanvect", IntArrayType, (union AnyValue *)&ScanVect, FALSE);
+    VariableDefinePlatformVar(NULL, "neuron", IntArrayType, (union AnyValue *)&NNVect, FALSE);
+    VariableDefinePlatformVar(NULL, "blobcnt", &IntType, (union AnyValue *)&Blobcnt, FALSE);
+    VariableDefinePlatformVar(NULL, "blobx1", &IntType, (union AnyValue *)&Blobx1, FALSE);
+    VariableDefinePlatformVar(NULL, "blobx2", &IntType, (union AnyValue *)&Blobx2, FALSE);
+    VariableDefinePlatformVar(NULL, "bloby1", &IntType, (union AnyValue *)&Bloby1, FALSE);
+    VariableDefinePlatformVar(NULL, "bloby2", &IntType, (union AnyValue *)&Bloby2, FALSE);
+    VariableDefinePlatformVar(NULL, "lcount", &IntType, (union AnyValue *)&Elcount, FALSE);
+    VariableDefinePlatformVar(NULL, "rcount", &IntType, (union AnyValue *)&Ercount, FALSE);
+    VariableDefinePlatformVar(NULL, "y1", &IntType, (union AnyValue *)&Iy1, FALSE);
+    VariableDefinePlatformVar(NULL, "y2", &IntType, (union AnyValue *)&Iy2, FALSE);
+    VariableDefinePlatformVar(NULL, "u1", &IntType, (union AnyValue *)&Iu1, FALSE);
+    VariableDefinePlatformVar(NULL, "u2", &IntType, (union AnyValue *)&Iu2, FALSE);
+    VariableDefinePlatformVar(NULL, "v1", &IntType, (union AnyValue *)&Iv1, FALSE);
+    VariableDefinePlatformVar(NULL, "v2", &IntType, (union AnyValue *)&Iv2, FALSE);
+    VariableDefinePlatformVar(NULL, "gpslat", &IntType, (union AnyValue *)&GPSlat, FALSE);
+    VariableDefinePlatformVar(NULL, "gpslon", &IntType, (union AnyValue *)&GPSlon, FALSE);
+    VariableDefinePlatformVar(NULL, "gpsalt", &IntType, (union AnyValue *)&GPSalt, FALSE);
+    VariableDefinePlatformVar(NULL, "gpsfix", &IntType, (union AnyValue *)&GPSfix, FALSE);
+    VariableDefinePlatformVar(NULL, "gpssat", &IntType, (union AnyValue *)&GPSsat, FALSE);
+    VariableDefinePlatformVar(NULL, "gpsutc", &IntType, (union AnyValue *)&GPSutc, FALSE);
+
+    LibraryInit(&GlobalTable, "platform library", &PlatformLibrary);
+}
+
diff --git a/platform/library_unix.c b/platform/library_unix.c
index fce00d3..a2df558 100644
--- a/platform/library_unix.c
+++ b/platform/library_unix.c
@@ -1,7 +1,7 @@
 #include "../picoc.h"
 
-void PlatformLibraryInit()
-{
+void UnixSetupFunc()
+{    
 }
 
 void Ctest (struct ParseState *Parser, struct Value *ReturnValue, struct Value **Param, int NumArgs) 
@@ -16,10 +16,14 @@ void Clineno (struct ParseState *Parser, struct Value *ReturnValue, struct Value
 }
 
 /* list of all library functions and their prototypes */
-struct LibraryFunction PlatformLibrary[] =
+struct LibraryFunction UnixFunctions[] =
 {
     { Ctest,        "void test(int);" },
     { Clineno,      "int lineno();" },
     { NULL,         NULL }
 };
 
+void PlatformLibraryInit()
+{
+    IncludeRegister("picoc_unix.h", &UnixSetupFunc, &UnixFunctions, NULL);
+}