diff --git a/Makefile b/Makefile
index 85c8b8f..b4f9d3c 100644
--- a/Makefile
+++ b/Makefile
@@ -11,8 +11,6 @@ TESTS := $(shell find unit-tests -name *.sh)
 INC_DIRS := $(shell find $(SRC_DIRS) -type d)
 INC_FLAGS := $(addprefix -I,$(INC_DIRS))
 
-TMP_DIR ?= ./tmp
-
 INDENT_FLAGS := -nbad -bap -nbc -br -brf -brs -c33 -cd33 -ncdb -ce -ci4 -cli4 \
 -d0 -di1 -nfc1 -i4 -ip0 -l75 -lp -npcs \
 -npsl -nsc -nsob -nss -nut -prs -l79 -ts2
@@ -43,7 +41,7 @@ test: $(TESTS) Makefile $(TARGET)
 
 .PHONY: clean
 clean:
-	$(RM) $(TARGET) $(OBJS) $(DEPS) $(SRC_DIRS)/*~ $(SRC_DIRS)/*/*~ $(TMP_DIR)/* *~ core
+	$(RM) $(TARGET) $(OBJS) $(DEPS) $(SRC_DIRS)/*~ $(SRC_DIRS)/*/*~ *~ core
 
 repl:
 	$(TARGET) -p 2> psse.log
diff --git a/src/arith/integer.c b/src/arith/integer.c
index 0e7cd6f..821b476 100644
--- a/src/arith/integer.c
+++ b/src/arith/integer.c
@@ -55,7 +55,7 @@ struct cons_pointer small_int_cache[SMALL_INT_LIMIT];
   * Low level integer arithmetic, do not use elsewhere.
   *
   * @param c a pointer to a cell, assumed to be an integer cell;
-  * @param op a character representing the operation: expected to be either
+  * @param op a character representing the operation: expectedto be either
   * '+' or '*'; behaviour with other values is undefined.
   * @param is_first_cell true if this is the first cell in a bignum
   * chain, else false.
@@ -128,8 +128,8 @@ struct cons_pointer make_integer( int64_t value, struct cons_pointer more ) {
 struct cons_pointer acquire_integer( int64_t value, struct cons_pointer more ) {
     struct cons_pointer result;
 
-    if ( !nilp( more) || value < 0 || value >= SMALL_INT_LIMIT) {
-        debug_print( L"acquire_integer passing to make_integer (outside small int range)\n", DEBUG_ALLOC );
+    if ( !nilp( more) || value >= SMALL_INT_LIMIT) {
+        debug_print( L"acquire_integer passing to make_integer (too large)\n", DEBUG_ALLOC );
         result = make_integer( value, more);
     } else {
         if ( !small_int_cache_initialised) {
@@ -239,7 +239,7 @@ struct cons_pointer add_integers( struct cons_pointer a,
         while ( !nilp( a ) || !nilp( b ) || carry != 0 ) {
             __int128_t av = cell_value( a, '+', is_first_cell );
             __int128_t bv = cell_value( b, '+', is_first_cell );
-            __int128_t rv = (av + bv) + carry;
+            __int128_t rv = av + bv + carry;
 
             debug_print( L"add_integers: av = ", DEBUG_ARITH );
             debug_print_128bit( av, DEBUG_ARITH );
@@ -251,22 +251,17 @@ struct cons_pointer add_integers( struct cons_pointer a,
             debug_print_128bit( rv, DEBUG_ARITH );
             debug_print( L"\n", DEBUG_ARITH );
 
-            if ( carry == 0 && ( rv >= 0 || rv < SMALL_INT_LIMIT)) {
-                result = acquire_integer( (int64_t)(rv & 0xffffffff), NIL);
-                break;
-            } else {
-                struct cons_pointer new = make_integer( 0, NIL );
-                carry = int128_to_integer( rv, cursor, new );
-                cursor = new;
+            struct cons_pointer new = make_integer( 0, NIL );
+            carry = int128_to_integer( rv, cursor, new );
+            cursor = new;
 
-                if ( nilp( result ) ) {
-                    result = cursor;
-                }
-
-                a = pointer2cell( a ).payload.integer.more;
-                b = pointer2cell( b ).payload.integer.more;
-                is_first_cell = false;
+            if ( nilp( result ) ) {
+                result = cursor;
             }
+
+            a = pointer2cell( a ).payload.integer.more;
+            b = pointer2cell( b ).payload.integer.more;
+            is_first_cell = false;
         }
     }
 
@@ -412,16 +407,10 @@ struct cons_pointer multiply_integers( struct cons_pointer a,
 struct cons_pointer integer_to_string_add_digit( int digit, int digits,
                                                  struct cons_pointer tail ) {
     wint_t character = btowc( hex_digits[digit] );
-    debug_printf( DEBUG_IO, L"integer_to_string_add_digit: digit is %d, digits is %d; returning: ", digit, digits);
-    struct cons_pointer r = ( digits % 3 == 0 ) ?
+    return ( digits % 3 == 0 ) ?
         make_string( L',', make_string( character,
                                         tail ) ) :
         make_string( character, tail );
-
-    debug_print_object( r, DEBUG_IO);
-    debug_println( DEBUG_IO);
-
-    return r;
 }
 
 /**
diff --git a/src/arith/ratio.c b/src/arith/ratio.c
index aa8e69f..f0095b1 100644
--- a/src/arith/ratio.c
+++ b/src/arith/ratio.c
@@ -45,17 +45,16 @@ int64_t least_common_multiple( int64_t m, int64_t n ) {
 
 struct cons_pointer simplify_ratio( struct cons_pointer pointer ) {
     struct cons_pointer result = pointer;
+    struct cons_space_object cell = pointer2cell( pointer );
+    struct cons_space_object dividend =
+        pointer2cell( cell.payload.ratio.dividend );
+    struct cons_space_object divisor =
+        pointer2cell( cell.payload.ratio.divisor );
 
-    if ( ratiop( pointer ) ) {
-        struct cons_space_object cell = pointer2cell( pointer );
-        struct cons_space_object dividend =
-            pointer2cell( cell.payload.ratio.dividend );
-        struct cons_space_object divisor =
-            pointer2cell( cell.payload.ratio.divisor );
-
-        if ( divisor.payload.integer.value == 1 ) {
-            result = pointer2cell( pointer ).payload.ratio.dividend;
-        } else {
+    if ( divisor.payload.integer.value == 1 ) {
+        result = pointer2cell( pointer ).payload.ratio.dividend;
+    } else {
+        if ( ratiop( pointer ) ) {
             int64_t ddrv = dividend.payload.integer.value,
                 drrv = divisor.payload.integer.value,
                 gcd = greatest_common_divisor( ddrv, drrv );
@@ -64,16 +63,13 @@ struct cons_pointer simplify_ratio( struct cons_pointer pointer ) {
                 if ( drrv / gcd == 1 ) {
                     result = acquire_integer( ddrv / gcd, NIL );
                 } else {
-                    debug_printf( DEBUG_ARITH, 
-                        L"simplify_ratio: %ld/%ld => %ld/%ld\n", ddrv, drrv, ddrv/gcd, drrv/gcd);
                     result =
                         make_ratio( acquire_integer( ddrv / gcd, NIL ),
                                     acquire_integer( drrv / gcd, NIL ) );
                 }
             }
         }
-    } 
-    // TODO: else throw exception?
+    }
 
     return result;
 
@@ -315,30 +311,23 @@ struct cons_pointer make_ratio( struct cons_pointer dividend,
     if ( integerp( dividend ) && integerp( divisor ) ) {
         inc_ref( dividend );
         inc_ref( divisor );
-        struct cons_pointer unsimplified = allocate_cell( RATIOTV );
-        struct cons_space_object *cell = &pointer2cell( unsimplified );
+        result = allocate_cell( RATIOTV );
+        struct cons_space_object *cell = &pointer2cell( result );
         cell->payload.ratio.dividend = dividend;
         cell->payload.ratio.divisor = divisor;
-
-        result = simplify_ratio( unsimplified);
-        if ( !eq( result, unsimplified)) { dec_ref( unsimplified); }
     } else {
         result =
             throw_exception( c_string_to_lisp_string
                              ( L"Dividend and divisor of a ratio must be integers" ),
                              NIL );
     }
-    // debug_print( L"make_ratio returning:\n", DEBUG_ARITH);
     debug_dump_object( result, DEBUG_ARITH );
 
     return result;
 }
 
 /**
- * True if a and be are identical rationals, else false.
- *
- * TODO: we need ways of checking whether rationals are equal
- * to floats and to integers.
+ * True if a and be are identical ratios, else false.
  */
 bool equal_ratio_ratio( struct cons_pointer a, struct cons_pointer b ) {
     bool result = false;
diff --git a/src/debug.c b/src/debug.c
index d139f8c..233e154 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -1,4 +1,4 @@
-/*
+/**
  * debug.c
  *
  * Better debug log messages.
@@ -25,17 +25,13 @@
 #include "io/print.h"
 
 /**
- * @brief the controlling flags for `debug_print`; set in `init.c`, q.v.
- *
- * Interpreted as a set o binary flags. The values are controlled by macros 
- * with names 'DEBUG_[A_Z]*' in `debug.h`, q.v.
+ * the controlling flags for `debug_print`; set in `init.c`, q.v.
  */
 int verbosity = 0;
 
 /**
- * @brief print this debug `message` to stderr, if `verbosity` matches `level`.
- *
- * `verbosity` is a set of flags, see debug_print.h; so you can
+ * print this debug `message` to stderr, if `verbosity` matches `level`.
+ * `verbosity is a set of flags, see debug_print.h; so you can
  * turn debugging on for only one part of the system.
  */
 void debug_print( wchar_t *message, int level ) {
@@ -48,11 +44,6 @@ void debug_print( wchar_t *message, int level ) {
 }
 
 /**
- * @brief print a 128 bit integer value to stderr, if `verbosity` matches `level`.
- *
- * `verbosity` is a set of flags, see debug_print.h; so you can
- * turn debugging on for only one part of the system.
- *
  * stolen from https://stackoverflow.com/questions/11656241/how-to-print-uint128-t-number-using-gcc
  */
 void debug_print_128bit( __int128_t n, int level ) {
@@ -77,9 +68,8 @@ void debug_print_128bit( __int128_t n, int level ) {
 }
 
 /**
- * @brief print a line feed to stderr, if `verbosity` matches `level`.
- *
- * `verbosity` is a set of flags, see debug_print.h; so you can
+ * print a line feed to stderr, if `verbosity` matches `level`.
+ * `verbosity is a set of flags, see debug_print.h; so you can
  * turn debugging on for only one part of the system.
  */
 void debug_println( int level ) {
@@ -93,10 +83,8 @@ void debug_println( int level ) {
 
 
 /**
- * @brief `wprintf` adapted for the debug logging system. 
- *
- * Print to stderr only if `verbosity` matches `level`. All other arguments
- * as for `wprintf`.
+ * `wprintf` adapted for the debug logging system. Print to stderr only
+ * `verbosity` matches `level`. All other arguments as for `wprintf`.
  */
 void debug_printf( int level, wchar_t *format, ... ) {
 #ifdef DEBUG
@@ -110,10 +98,8 @@ void debug_printf( int level, wchar_t *format, ... ) {
 }
 
 /**
- * @brief print the object indicated by this `pointer` to stderr, if `verbosity`
- * matches `level`.
- *
- * `verbosity` is a set of flags, see debug_print.h; so you can
+ * print the object indicated by this `pointer` to stderr, if `verbosity`
+ * matches `level`.`verbosity is a set of flags, see debug_print.h; so you can
  * turn debugging on for only one part of the system.
  */
 void debug_print_object( struct cons_pointer pointer, int level ) {
@@ -128,10 +114,7 @@ void debug_print_object( struct cons_pointer pointer, int level ) {
 }
 
 /**
- * @brief Like `dump_object`, q.v., but protected by the verbosity mechanism.
- *
- * `verbosity` is a set of flags, see debug_print.h; so you can
- * turn debugging on for only one part of the system.
+ * Like `dump_object`, q.v., but protected by the verbosity mechanism.
  */
 void debug_dump_object( struct cons_pointer pointer, int level ) {
 #ifdef DEBUG
diff --git a/src/debug.h b/src/debug.h
index 41c1618..babbaea 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -1,4 +1,4 @@
-/*
+/**
  * debug.h
  *
  * Better debug log messages.
@@ -13,67 +13,14 @@
 #ifndef __debug_print_h
 #define __debug_print_h
 
-/**
- * @brief Print messages debugging memory allocation. 
- *
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_ALLOC 1
-
-/**
- * @brief Print messages debugging arithmetic operations.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_ARITH 2
-
-/**
- * @brief Print messages debugging symbol binding.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_BIND 4
-
-/**
- * @brief Print messages debugging bootstrapping and teardown.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_BOOTSTRAP 8
-
-/**
- * @brief Print messages debugging evaluation.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_EVAL 16
-
-/**
- * @brief Print messages debugging input/output operations.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_IO 32
-
-/**
- * @brief Print messages debugging lambda functions (interpretation).
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_LAMBDA 64
-
-/**
- * @brief Print messages debugging the read eval print loop.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_REPL 128
-
-/**
- * @brief Print messages debugging stack operations.
- * 
- * Flag interpretation for the value of `verbosity`, defined in `debug.c`, q.v.
- */
 #define DEBUG_STACK 256
 
 extern int verbosity;
diff --git a/src/init.c b/src/init.c
index 7c4bdc3..17f8d36 100644
--- a/src/init.c
+++ b/src/init.c
@@ -65,25 +65,6 @@ struct cons_pointer check_exception( struct cons_pointer pointer, char * locatio
     return result;
 }
 
-struct cons_pointer init_name_symbol = NIL;
-struct cons_pointer init_primitive_symbol = NIL;
-
-void maybe_bind_init_symbols() {
-    if ( nilp( init_name_symbol)) {
-        init_name_symbol = c_string_to_lisp_keyword( L"name" );
-    }
-    if ( nilp( init_primitive_symbol)) {
-        init_primitive_symbol = c_string_to_lisp_keyword( L"primitive" );
-    }
-    if ( nilp( privileged_symbol_nil)) {
-        privileged_symbol_nil = c_string_to_lisp_symbol( L"nil");
-    }
-}
-
-void free_init_symbols() {
-    dec_ref( init_name_symbol);
-    dec_ref( init_primitive_symbol);
-}
 
 /**
  * Bind this compiled `executable` function, as a Lisp function, to
@@ -92,75 +73,45 @@ void free_init_symbols() {
  * the name on the source pointer. Would make stack frames potentially
  * more readable and aid debugging generally.
  */
-struct cons_pointer bind_function( wchar_t *name, struct cons_pointer ( *executable )
+void bind_function( wchar_t *name, struct cons_pointer ( *executable )
                      ( struct stack_frame *,
                        struct cons_pointer, struct cons_pointer ) ) {
     struct cons_pointer n = c_string_to_lisp_symbol( name );
     struct cons_pointer meta =
-        make_cons( make_cons( init_primitive_symbol, TRUE ),
-                   make_cons( make_cons( init_name_symbol, n ),
+        make_cons( make_cons( c_string_to_lisp_keyword( L"primitive" ), TRUE ),
+                   make_cons( make_cons( c_string_to_lisp_keyword( L"name" ),
+                                         n ),
                               NIL ) );
 
-    struct cons_pointer r = check_exception( 
-        deep_bind( n, make_function( meta, executable ) ),
+    check_exception( deep_bind( n, make_function( meta, executable ) ),
                     "bind_function");
-    
-    dec_ref( n);
-
-    return r;
 }
 
 /**
  * Bind this compiled `executable` function, as a Lisp special form, to
  * this `name` in the `oblist`.
  */
-struct cons_pointer bind_special( wchar_t *name, struct cons_pointer ( *executable )
+void bind_special( wchar_t *name, struct cons_pointer ( *executable )
                     ( struct stack_frame *,
                       struct cons_pointer, struct cons_pointer ) ) {
     struct cons_pointer n = c_string_to_lisp_symbol( name );
-
     struct cons_pointer meta =
-        make_cons( make_cons( init_primitive_symbol, TRUE ),
-                   make_cons( make_cons( init_name_symbol, n), NIL ) );
+        make_cons( make_cons( c_string_to_lisp_keyword( L"primitive" ), TRUE ),
+                   make_cons( make_cons( c_string_to_lisp_keyword( L"name" ),
+                                         n ),
+                              NIL ) );
 
-    struct cons_pointer r = 
-        check_exception(deep_bind( n, make_special( meta, executable ) ),
+    check_exception(deep_bind( n, make_special( meta, executable ) ),
                     "bind_special");
-    
-    dec_ref( n);
-
-    return r;
-}
-
-/**
- * Bind this `value` to this `symbol` in the `oblist`.
- */
-struct cons_pointer 
-bind_symbol_value( struct cons_pointer symbol, struct cons_pointer value, bool lock) {
-    struct cons_pointer r = check_exception( 
-        deep_bind( symbol, value ),
-            "bind_symbol_value");
-
-    if ( lock && !exceptionp( r)){
-        struct cons_space_object * cell = & pointer2cell( r);
-
-        cell->count = UINT32_MAX;
-    }
-
-    return r;
 }
 
 /**
  * Bind this `value` to this `name` in the `oblist`.
  */
-struct cons_pointer bind_value( wchar_t *name, struct cons_pointer value, bool lock ) {
-    struct cons_pointer p = c_string_to_lisp_symbol( name );
-
-    struct cons_pointer r = bind_symbol_value( p, value, lock);
-
-    dec_ref( p);
-
-    return r;
+struct cons_pointer bind_value( wchar_t *name, struct cons_pointer value ) {
+    return check_exception( 
+        deep_bind( c_string_to_lisp_symbol( name ), value ),
+            "bind_value");
 }
 
 void print_banner(  ) {
@@ -236,15 +187,21 @@ int main( int argc, char *argv[] ) {
         }
     }
 
-    initialise_cons_pages();
-
-    maybe_bind_init_symbols();
-
-
     if ( show_prompt ) {
         print_banner(  );
     }
 
+    initialise_cons_pages(  );
+
+//     TODO: oblist-as-hashmap (which is what we ultimately need) is failing hooribly.
+//     What actually goes wrong is: 
+//     1. the hashmap is created; 
+//     2. everything bound in init seems to get initialised properly;
+//     3. the REPL starts up;
+//     4. Anything typed into the REPL (except ctrl-D) results in immediate segfault.
+//     5. If ctrl-D is the first thing typed into the REPL, shutdown proceeds normally.
+//     Hypothesis: binding stuff into a hashmap oblist either isn't happening or 
+//      is wrking ok, but retrieving from a hashmap oblist is failing.
     debug_print( L"About to initialise oblist\n", DEBUG_BOOTSTRAP );
 
     oblist = make_hashmap( 32, NIL, TRUE );
@@ -254,8 +211,8 @@ int main( int argc, char *argv[] ) {
     /*
      * privileged variables (keywords)
      */
-    bind_symbol_value( privileged_symbol_nil, NIL, true);
-    bind_value( L"t", TRUE, true );
+    bind_value( L"nil", NIL );
+    bind_value( L"t", TRUE );
 
     /*
      * standard input, output, error and sink streams
@@ -276,7 +233,7 @@ int main( int argc, char *argv[] ) {
                                                 ( L"url" ),
                                                 c_string_to_lisp_string
                                                 ( L"system:standard input" ) ),
-                                                NIL ) ), false );
+                                                NIL ) ) );
     lisp_io_out = bind_value( C_IO_OUT,
                 make_write_stream( file_to_url_file( stdout ),
                                    make_cons( make_cons
@@ -284,26 +241,26 @@ int main( int argc, char *argv[] ) {
                                                 ( L"url" ),
                                                 c_string_to_lisp_string
                                                 ( L"system:standard output]" ) ),
-                                              NIL ) ), false);
+                                              NIL ) ) );
     bind_value( L"*log*", make_write_stream( file_to_url_file( stderr ),
                                              make_cons( make_cons
                                                         ( c_string_to_lisp_keyword
                                                           ( L"url" ),
                                                           c_string_to_lisp_string
                                                           ( L"system:standard log" ) ),
-                                                        NIL ) ), false );
+                                                        NIL ) ) );
     bind_value( L"*sink*", make_write_stream( sink,
                                               make_cons( make_cons
                                                          ( c_string_to_lisp_keyword
                                                            ( L"url" ),
                                                            c_string_to_lisp_string
                                                            ( L"system:standard sink" ) ),
-                                                         NIL ) ), false );
+                                                         NIL ) ) );
     /*
      * the default prompt
      */
     prompt_name = bind_value( L"*prompt*",
-                show_prompt ? c_string_to_lisp_symbol( L":: " ) : NIL, false );
+                show_prompt ? c_string_to_lisp_symbol( L":: " ) : NIL );
     /*
      * primitive function operations
      */
@@ -370,15 +327,13 @@ int main( int argc, char *argv[] ) {
 
     repl( show_prompt );
 
+    debug_print( L"Freeing oblist\n", DEBUG_BOOTSTRAP );
+    dec_ref( oblist );
     debug_dump_object( oblist, DEBUG_BOOTSTRAP );
     if ( dump_at_end ) {
         dump_pages( file_to_url_file( stdout ) );
     }
 
-    debug_print( L"Freeing oblist\n", DEBUG_BOOTSTRAP );
-    dec_ref( oblist );
-    free_init_symbols();
-
     summarise_allocation(  );
     curl_global_cleanup(  );
     return ( 0 );
diff --git a/src/io/io.c b/src/io/io.c
index 66c51c2..2db9492 100644
--- a/src/io/io.c
+++ b/src/io/io.c
@@ -413,8 +413,12 @@ struct cons_pointer get_default_stream( bool inputp, struct cons_pointer env ) {
     struct cons_pointer stream_name =
          inputp ? lisp_io_in : lisp_io_out;
 
+    inc_ref( stream_name );
+
     result = c_assoc( stream_name, env );
 
+    dec_ref( stream_name );
+
     return result;
 }
 
@@ -426,7 +430,7 @@ struct cons_pointer get_default_stream( bool inputp, struct cons_pointer env ) {
  * to append, or error if the URL is faulty or indicates an unavailable
  * resource.
  *
- * * (open url)
+ * * (read-char stream)
  *
  * @param frame my stack_frame.
  * @param frame_pointer a pointer to my stack_frame.
@@ -520,8 +524,6 @@ lisp_read_char( struct stack_frame *frame, struct cons_pointer frame_pointer,
  * Function: return a string representing all characters from the stream
  * indicated by arg 0; further arguments are ignored.
  *
- * TODO: it should be possible to optionally pass a string URL to this function,
- *
  * * (slurp stream)
  *
  * @param frame my stack_frame.
diff --git a/src/io/print.c b/src/io/print.c
index deea087..f4aab9f 100644
--- a/src/io/print.c
+++ b/src/io/print.c
@@ -170,9 +170,13 @@ struct cons_pointer print( URL_FILE * output, struct cons_pointer pointer ) {
             url_fputwc( L'>', output );
             break;
         case INTEGERTV:
-            struct cons_pointer s = integer_to_string( pointer, 10 );
-            print_string_contents( output, s );
-            dec_ref( s );
+            if ( nilp( cell.payload.integer.more)) {
+                url_fwprintf( output, L"%ld", cell.payload.integer.value);
+            } else {
+                struct cons_pointer s = integer_to_string( pointer, 10 );
+                print_string_contents( output, s );
+                dec_ref( s );
+            }
             break;
         case KEYTV:
             url_fputws( L":", output );
diff --git a/src/memory/consspaceobject.c b/src/memory/consspaceobject.c
index 5a234da..8a8ed2a 100644
--- a/src/memory/consspaceobject.c
+++ b/src/memory/consspaceobject.c
@@ -80,7 +80,7 @@ struct cons_pointer inc_ref( struct cons_pointer pointer ) {
 struct cons_pointer dec_ref( struct cons_pointer pointer ) {
   struct cons_space_object *cell = &pointer2cell( pointer );
 
-  if ( cell->count > 0 && cell->count != UINT32_MAX) {
+  if ( cell->count > 0 ) {
     cell->count--;
 
     if ( cell->count == 0 ) {
@@ -307,6 +307,10 @@ struct cons_pointer make_string_like_thing( wint_t c, struct cons_pointer tail,
 
     cell->payload.string.character = c;
     cell->payload.string.cdr = tail;
+    /* \todo There's a problem here. Sometimes the offsets on
+     * strings are quite massively off. Fix is probably
+     * cell->payload.string.cdr = tail */
+    //cell->payload.string.cdr.offset = tail.offset;
 
     cell->payload.string.hash = calculate_hash( c, tail );
   } else {
diff --git a/src/memory/hashmap.c b/src/memory/hashmap.c
index d268bd9..15b5550 100644
--- a/src/memory/hashmap.c
+++ b/src/memory/hashmap.c
@@ -94,6 +94,9 @@ struct cons_pointer lisp_make_hashmap( struct stack_frame *frame,
         }
     }
 
+    // TODO: I am not sure this is right! We do not inc_ref a string when
+    // we make it.
+    inc_ref(result);
     return result;
 }
 
@@ -115,6 +118,9 @@ struct cons_pointer lisp_hashmap_put( struct stack_frame *frame,
 
     struct cons_pointer result = hashmap_put( mapp, key, val );
     struct cons_space_object *cell = &pointer2cell( result);
+    // if (cell->count <= 1) {
+    //     inc_ref( result); // TODO: I DO NOT BELIEVE this is the right place! 
+    // }
     return result;
 
     // TODO: else clone and return clone.
diff --git a/src/ops/intern.c b/src/ops/intern.c
index d2be616..3fb38d3 100644
--- a/src/ops/intern.c
+++ b/src/ops/intern.c
@@ -36,7 +36,7 @@
 // #include "print.h"
 
 /**
- * @brief The global object list/or, to put it differently, the root namespace.
+ * The global object list/or, to put it differently, the root namespace.
  * What is added to this during system setup is 'global', that is,
  * visible to all sessions/threads. What is added during a session/thread is local to
  * that session/thread (because shallow binding). There must be some way for a user to
@@ -47,12 +47,6 @@
  */
 struct cons_pointer oblist = NIL;
 
-/**
- * @brief the symbol `NIL`, which is special!
- * 
- */
-struct cons_pointer privileged_symbol_nil = NIL;
-
 /**
  * Return a hash value for the structure indicated by `ptr` such that if
  * `x`,`y` are two separate structures whose print representation is the same
@@ -169,6 +163,7 @@ struct cons_pointer hashmap_keys( struct cons_pointer mapp ) {
                   !nilp( c ); c = c_cdr( c ) ) {
                 result = make_cons( c_car( c_car( c ) ), result );
             }
+
         }
     }
 
@@ -265,8 +260,6 @@ struct cons_pointer clone_hashmap( struct cons_pointer ptr ) {
     return result;
 }
 
-// (keys set let quote read equal *out* *log* oblist cons source cond close meta mapcar negative? open subtract eval nλ *in* *sink* cdr set! reverse slurp try assoc eq add list time car t *prompt* absolute append apply divide exception get-hash hashmap inspect metadata multiply print put! put-all! read-char repl throw type + * - / = lambda λ nlambda progn)
-
 /**
  * Implementation of interned? in C. The final implementation if interned? will
  * deal with stores which can be association lists or hashtables or hybrids of
@@ -301,8 +294,6 @@ internedp( struct cons_pointer key, struct cons_pointer store ) {
         //     }
         if (!nilp( c_assoc( key, store))) {
             result = key;
-        } else if ( equal( key, privileged_symbol_nil)) {
-            result = privileged_symbol_nil;
         }
     } else {
         debug_print( L"`", DEBUG_BIND );
diff --git a/src/ops/intern.h b/src/ops/intern.h
index abc6f91..6be9cbc 100644
--- a/src/ops/intern.h
+++ b/src/ops/intern.h
@@ -20,8 +20,6 @@
 #ifndef __intern_h
 #define __intern_h
 
-extern struct cons_pointer privileged_symbol_nil;
-
 extern struct cons_pointer oblist;
 
 uint32_t get_hash( struct cons_pointer ptr );
diff --git a/src/ops/lispops.c b/src/ops/lispops.c
index c0765cd..2f549e4 100644
--- a/src/ops/lispops.c
+++ b/src/ops/lispops.c
@@ -1273,6 +1273,8 @@ struct cons_pointer lisp_repl( struct stack_frame *frame,
     struct cons_pointer old_oblist = oblist;
     struct cons_pointer new_env = env;
     
+    inc_ref( env );
+
     if (truep(frame->arg[0])) {
         new_env = set( prompt_name, frame->arg[0], new_env);
     }
@@ -1336,6 +1338,7 @@ struct cons_pointer lisp_repl( struct stack_frame *frame,
 
         expr = lisp_read( get_stack_frame( frame_pointer ), frame_pointer,
                           new_env );
+        inc_ref( expr );
 
         if ( exceptionp( expr )
              && url_feof( pointer2cell( input ).payload.stream.stream ) ) {
@@ -1353,7 +1356,7 @@ struct cons_pointer lisp_repl( struct stack_frame *frame,
     dec_ref( input );
     dec_ref( output );
     dec_ref( prompt_name );
-    dec_ref( new_env);
+    dec_ref( env );
 
     debug_printf(DEBUG_REPL, L"Leaving inner repl\n");
     
diff --git a/unit-tests/add.sh b/unit-tests/add.sh
index ca6f2a8..2802c3a 100755
--- a/unit-tests/add.sh
+++ b/unit-tests/add.sh
@@ -1,92 +1,79 @@
 #!/bin/bash
 
-result=0;
-
-echo -n "$0: Add two small integers... "
-
 expected='5'
-actual=`echo "(add 2 3)" | target/psse 2>/dev/null | sed -r '/^\s*$/d' | tail -1`
+actual=`echo "(add 2 3)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Add float to integer... "
-
 expected='5.5'
-actual=`echo "(add 2.5 3)" | target/psse 2>/dev/null | sed -r '/^\s*$/d' | tail -1`
+actual=`echo "(add 2.5 3)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
+    exit 0
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Add two rationals... "
-
 expected='1/4'
-actual=`echo "(+ 3/14 1/28)" | target/psse 2>/dev/null | sed -r '/^\s*$/d' | tail -1`
+actual=`echo "(+ 3/14 1/28)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Add an integer to a rational... "
-
 # (+ integer ratio) should be ratio
 expected='25/4'
-actual=`echo "(+ 6 1/4)" | target/psse  2>/dev/null | sed -r '/^\s*$/d' | tail -1`
+actual=`echo "(+ 6 1/4)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Add a rational to an integer... "
-
 # (+ ratio integer) should be ratio
 expected='25/4'
-actual=`echo "(+ 1/4 6)" | target/psse 2>/dev/null | sed -r '/^\s*$/d' | tail -1`
+actual=`echo "(+ 1/4 6)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Add a real to a rational... "
-
 # (+ real ratio) should be real
 # for this test, trailing zeros can be ignored
 expected='6.25'
 actual=`echo "(+ 6.000000001 1/4)" |\
   target/psse 2> /dev/null |\
-  sed -r '/^\s*$/d' |\
-  sed 's/0*$//' 
+  sed 's/0*$//' |\
+  head -2 |\
+  tail -1`
 
 outcome=`echo "sqrt((${expected} - ${actual})^2) < 0.0000001" | bc`
 
-if [ "${outcome}" -eq "1" ]
+if [ "${outcome}" = "1" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc `
+    exit 1
 fi
 
-exit ${result}
diff --git a/unit-tests/append.sh b/unit-tests/append.sh
index 972aa04..0f6fb30 100755
--- a/unit-tests/append.sh
+++ b/unit-tests/append.sh
@@ -1,44 +1,24 @@
 #!/bin/bash
 
-return=0;
-
-echo -n "$0: Append two lists... "
-
 expected='(a b c d e f)'
-actual=`echo "(append '(a b c) '(d e f))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(append '(a b c) '(d e f))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Append two strings... "
-
 expected='"hellodere"'
-actual=`echo '(append "hello" "dere")' | target/psse 2>/dev/null | tail -1`
+actual=`echo '(append "hello" "dere")' | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: Append keyword to string should error... "
-
-expected='Exception:'
-actual=`echo '(append "hello" :dere)' | target/psse 2>/dev/null | sed -r '/^\s*$/d' | awk '{print $1}'`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-else
-    echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
-fi
-
-exit ${return}
\ No newline at end of file
diff --git a/unit-tests/apply.sh b/unit-tests/apply.sh
index aa8171a..811fdae 100755
--- a/unit-tests/apply.sh
+++ b/unit-tests/apply.sh
@@ -1,29 +1,13 @@
 #!/bin/bash
 
-result=1
-
-echo -n "$0: Apply function to one argument... "
 expected='1'
-actual=`echo "(apply 'add '(1))"| target/psse 2>/dev/null | tail -1`
+actual=`echo "(apply 'add '(1))"| target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
+    exit 0
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    exit 1
 fi
-
-echo -n "$0: Apply function to multiple arguments... "
-expected='3'
-actual=`echo "(apply 'add '(1 2))"| target/psse 2>/dev/null | tail -1`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-else
-    echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
-fi
-
-exit ${result}
diff --git a/unit-tests/bignum-add.sh b/unit-tests/bignum-add.sh
index aa0aef4..293e1e5 100755
--- a/unit-tests/bignum-add.sh
+++ b/unit-tests/bignum-add.sh
@@ -9,7 +9,7 @@ a=1152921504606846975
 b=1
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1`
@@ -20,17 +20,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
-echo -n "$0: checking no bignum was created: "
-grep -v 'BIGNUM!' tmp/psse.log > /dev/null
+echo -n "checking no bignum was created: "
+grep -v 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -40,7 +40,7 @@ a='1152921504606846976'
 b=1
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -52,17 +52,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 
@@ -73,7 +73,7 @@ a='1152921504606846977'
 b=1
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -85,17 +85,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -106,7 +106,7 @@ a=1
 b=1152921504606846977
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -118,17 +118,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
-echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+echo -n "checking a bignum was created: "
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 
@@ -139,7 +139,7 @@ a=1152921504606846977
 c=`echo "$a + $a" | bc`
 echo -n "$0 => adding $a to $a: "
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -150,7 +150,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -160,7 +160,7 @@ a=1152921504606846977
 c=`echo "$a * 5" | bc`
 echo -n "$0 => adding $a, $a $a, $a, $a: "
 expected='t'
-output=`echo "(= (+ $a $a $a $a $a) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $a $a $a $a) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -171,7 +171,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 
@@ -183,7 +183,7 @@ a=10000000000000000000
 b=10000000000000000000
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -195,17 +195,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 
@@ -216,7 +216,7 @@ a=1
 b=1329227995784915872903807060280344576
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -228,17 +228,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 
@@ -250,7 +250,7 @@ a=1
 b=3064991081731777716716694054300618367237478244367204352
 c=`echo "$a + $b" | bc`
 expected='t'
-output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>tmp/psse.log`
+output=`echo "(= (+ $a $b) $c)" | target/psse -v 2 2>psse.log`
 
 actual=`echo $output |\
   tail -1 |\
@@ -262,17 +262,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 echo -n "$0 => checking a bignum was created: "
-grep 'BIGNUM!' tmp/psse.log > /dev/null
+grep 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    return=`echo "${return} + 1" | bc`
+    return=1
 fi
 
 exit ${return}
\ No newline at end of file
diff --git a/unit-tests/bignum-subtract.sh b/unit-tests/bignum-subtract.sh
index 814d901..19c673f 100755
--- a/unit-tests/bignum-subtract.sh
+++ b/unit-tests/bignum-subtract.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-result=0
+return=0
 
 #####################################################################
 # subtract a smallnum from a smallnum to produce a smallnum
@@ -20,17 +20,17 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
-echo -n "$0 => checking no bignum was created: "
+echo -n "checking no bignum was created: "
 grep -v 'BIGNUM!' psse.log > /dev/null
 if [ $? -eq "0" ]
 then
     echo "OK"
 else
     echo "Fail"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -51,7 +51,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -71,7 +71,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
 
@@ -93,7 +93,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
 #####################################################################
@@ -113,7 +113,7 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    return=1
 fi
 
-exit ${result}
\ No newline at end of file
+exit ${return}
\ No newline at end of file
diff --git a/unit-tests/complex-list.sh b/unit-tests/complex-list.sh
index 6a6307b..3e84d79 100755
--- a/unit-tests/complex-list.sh
+++ b/unit-tests/complex-list.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='(1 2 3 ("Fred") nil 77,354)'
-actual=`echo "'(1 2 3 (\"Fred\") () 77354)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "'(1 2 3 (\"Fred\") () 77354)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/cond.sh b/unit-tests/cond.sh
index 86f0e9f..69952c9 100755
--- a/unit-tests/cond.sh
+++ b/unit-tests/cond.sh
@@ -2,30 +2,26 @@
 
 result=0
 
-echo -n "$0: cond with one clause... "
-
 expected='5'
-actual=`echo "(cond ((equal 2 2) 5))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(cond ((equal 2 2) 5))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
   echo "OK"
 else
   echo "Fail: expected '${expected}', got '${actual}'"
-  result=`echo "${result} + 1" | bc`
+  result=1
 fi
 
-echo -n "$0: cond with two clauses... "
-
 expected='"should"'
-actual=`echo "(cond ((equal 2 3) \"shouldn't\")(t \"should\"))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(cond ((equal 2 3) \"shouldn't\")(t \"should\"))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
  else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
\ No newline at end of file
diff --git a/unit-tests/let.sh b/unit-tests/let.sh
index 037a96a..a4ab77f 100755
--- a/unit-tests/let.sh
+++ b/unit-tests/let.sh
@@ -2,28 +2,26 @@
 
 result=0
 
-echo -n "$0: let with two bindings, one form in body..."
 expected='11'
-actual=`echo "(let ((a . 5)(b . 6)) (+ a b))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(let ((a . 5)(b . 6)) (+ a b))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '$expected', got '$actual'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: let with two bindings, two forms in body..."
 expected='1'
-actual=`echo "(let ((a . 5)(b . 6)) (+ a b) (- b a))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(let ((a . 5)(b . 6)) (+ a b) (- b a))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '$expected', got '$actual'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
\ No newline at end of file
diff --git a/unit-tests/list-test,sh b/unit-tests/list-test,sh
new file mode 100644
index 0000000..12fdd60
--- /dev/null
+++ b/unit-tests/list-test,sh
@@ -0,0 +1,42 @@
+#!/bin/bash
+
+result=0
+
+expected="(0 1 2 3 4 5 6 7 8 9 a b c d e f)"
+
+actual=`echo "(list 0 1 2 3 4 5 6 7 8 9 'a 'b 'c 'd 'e 'f)" | target/psse | tail -1`
+
+if [ "${expected}" = "${actual}" ]
+then
+    echo "OK"
+else
+    echo "Fail: expected '$expected', got '$actual'"
+    result=1
+fi
+
+expected="(0 1 2 3 4)"
+
+actual=`echo "(list 0 1 2 3 4)" | target/psse | tail -1`
+
+if [ "${expected}" = "${actual}" ]
+then
+    echo "OK"
+else
+    echo "Fail: expected '$expected', got '$actual'"
+    result=1
+fi
+
+expected="(0 1 2 3 4 5 6 7)"
+
+actual=`echo "(list 0 1 2 3 4 5 6 7)" | target/psse | tail -1`
+
+if [ "${expected}" = "${actual}" ]
+then
+    echo "OK"
+    exit 0
+else
+    echo "Fail: expected '$expected', got '$actual'"
+    result=1
+fi
+
+exit ${result}
\ No newline at end of file
diff --git a/unit-tests/list-test.sh b/unit-tests/list-test.sh
deleted file mode 100644
index ef94631..0000000
--- a/unit-tests/list-test.sh
+++ /dev/null
@@ -1,47 +0,0 @@
-#!/bin/bash
-
-result=0
-
-echo -n "$0: flat list with 16 elements... "
-expected="(0 1 2 3 4 5 6 7 8 9 a b c d e f)"
-
-actual=`echo "(list 0 1 2 3 4 5 6 7 8 9 'a 'b 'c 'd 'e 'f)" |\
-    target/psse 2>/dev/null |\
-    tail -1`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-else
-    echo "Fail: expected '$expected', got '$actual'"
-    result=`echo "${result} + 1" | bc`
-fi
-
-echo -n "$0: flat list with 5 elements... "
-expected="(0 1 2 3 4)"
-
-actual=`echo "(list 0 1 2 3 4)" | target/psse 2>/dev/null | tail -1`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-else
-    echo "Fail: expected '$expected', got '$actual'"
-    result=`echo "${result} + 1" | bc`
-fi
-
-echo -n "$0: flat list with 8 elements... "
-expected="(0 1 2 3 4 5 6 7)"
-
-actual=`echo "(list 0 1 2 3 4 5 6 7)" | target/psse 2>/dev/null | tail -1`
-
-if [ "${expected}" = "${actual}" ]
-then
-    echo "OK"
-    exit 0
-else
-    echo "Fail: expected '$expected', got '$actual'"
-    result=`echo "${result} + 1" | bc`
-fi
-
-exit ${result}
\ No newline at end of file
diff --git a/unit-tests/many-args.sh b/unit-tests/many-args.sh
index bbbb6e8..449f7d8 100755
--- a/unit-tests/many-args.sh
+++ b/unit-tests/many-args.sh
@@ -1,30 +1,28 @@
 #!/bin/bash
 
-result=0
-
-echo -n "$0: plus with fifteen arguments... "
+result=1
 
 expected="120"
-actual=`echo "(+ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(+ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: check that all the args are actually being evaluated... "
+# check that all the args are actually being evaluated...
 expected="120"
-actual=`echo "(+ (+ 0 1) (+ 0 2) (+ 0 3) (+ 0 4) (+ 0 5) (+ 0 6) (+ 0 7) (+ 0 8) (+ 0 9) (+ 0 10) (+ 0 11) (+ 0 12) (+ 0 13) (+ 0 14 ) (+ 0 15))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(+ (+ 0 1) (+ 0 2) (+ 0 3) (+ 0 4) (+ 0 5) (+ 0 6) (+ 0 7) (+ 0 8) (+ 0 9) (+ 0 10) (+ 0 11) (+ 0 12) (+ 0 13) (+ 0 14 ) (+ 0 15))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-exit ${result}
+return ${result}
diff --git a/unit-tests/map.sh b/unit-tests/map.sh
index 0e698f0..90857ef 100755
--- a/unit-tests/map.sh
+++ b/unit-tests/map.sh
@@ -5,9 +5,9 @@ result=0
 #####################################################################
 # Create an empty map using map notation
 expected='{}'
-actual=`echo "$expected" | target/psse 2>/dev/null | tail -1`
+actual=`echo "$expected" | target/psse | tail -1`
 
-echo -n "$0: Empty map using compact map notation... "
+echo -n "Empty map using compact map notation: "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
@@ -19,7 +19,7 @@ fi
 #####################################################################
 # Create an empty map using make-map
 expected='{}'
-actual=`echo "(hashmap)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(hashmap)" | target/psse | tail -1`
 
 echo -n "Empty map using (make-map): "
 if [ "${expected}" = "${actual}" ]
@@ -35,9 +35,9 @@ fi
 # significant at this stage, but in the long term should be sorted
 # alphanumerically
 expected='{:one 1, :two 2, :three 3}'
-actual=`echo "{:one 1 :two 2 :three 3}" | target/psse 2>/dev/null | tail -1`
+actual=`echo "{:one 1 :two 2 :three 3}" | target/psse | tail -1`
 
-echo -n "$0: Map using map notation... "
+echo -n "Map using map notation: "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
@@ -51,10 +51,9 @@ fi
 # significant at this stage, but in the long term should be sorted
 # alphanumerically
 expected='{:one 1, :two 2, :three 3}'
-actual=`echo "(hashmap nil nil '((:one . 1)(:two . 2)(:three . 3)))" |\
-    target/psse 2>/dev/null | tail -1`
+actual=`echo "(hashmap nil nil '((:one . 1)(:two . 2)(:three . 3)))" | target/psse | tail -1`
 
-echo -n "$0: Map using (hashmap) with arguments... "
+echo -n "Map using (hashmap): "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
@@ -66,9 +65,9 @@ fi
 #####################################################################
 # Keyword in function position
 expected='2'
-actual=`echo "(:two {:one 1 :two 2 :three 3})" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(:two {:one 1 :two 2 :three 3})" | target/psse | tail -1`
 
-echo -n "$0: Keyword in function position... "
+echo -n "Keyword in function position: "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
@@ -81,9 +80,9 @@ fi
 #####################################################################
 # Map in function position
 expected='2'
-actual=`echo "({:one 1 :two 2 :three 3} :two)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "({:one 1 :two 2 :three 3} :two)" | target/psse | tail -1`
 
-echo -n "$0: Map in function position... "
+echo -n "Map in function position: "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
diff --git a/unit-tests/multiply.sh b/unit-tests/multiply.sh
index 1e2da1f..aeac7e8 100755
--- a/unit-tests/multiply.sh
+++ b/unit-tests/multiply.sh
@@ -2,30 +2,26 @@
 
 result=0
 
-echo -n "$0: multiply two integers... "
-
 expected='6'
-actual=`echo "(multiply 2 3)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(multiply 2 3)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: multiply a real by an integer... "
-
 expected='7.5'
-actual=`echo "(multiply 2.5 3)" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(multiply 2.5 3)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
\ No newline at end of file
diff --git a/unit-tests/nil.sh b/unit-tests/nil.sh
index c15f0b1..fcbf530 100755
--- a/unit-tests/nil.sh
+++ b/unit-tests/nil.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected=nil
-actual=`echo 'nil' | target/psse 2>/dev/null | tail -1`
+actual=`echo 'nil' | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/path-notation.sh b/unit-tests/path-notation.sh
index cbb9dea..70610b0 100755
--- a/unit-tests/path-notation.sh
+++ b/unit-tests/path-notation.sh
@@ -4,9 +4,8 @@ result=0
 
 #####################################################################
 # Create a path from root using compact path notation
-echo -n "$0: Create a path from root using compact path notation... "
 expected='(-> oblist :users :simon :functions (quote assoc))'
-actual=`echo "'/:users:simon:functions/assoc" | target/psse 2>&1 | tail -1`
+actual=`echo "'/:users:simon:functions/assoc" | target/psse | tail -1`
 
 echo -n "Path from root (oblist) using compact notation: "
 if [ "${expected}" = "${actual}" ]
@@ -14,21 +13,21 @@ then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 #####################################################################
 # Create a path from the current session using compact path notation
-echo -n "$0: Create a path from the current session using compact path notation... "
 expected='(-> session :input-stream)'
-actual=`echo "'$:input-stream" | target/psse 2>/dev/null | tail -1`
+actual=`echo "'$:input-stream" | target/psse | tail -1`
 
+echo -n "Path from current session using compact notation: "
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
diff --git a/unit-tests/progn.sh b/unit-tests/progn.sh
index ea6cf7b..b9b44eb 100755
--- a/unit-tests/progn.sh
+++ b/unit-tests/progn.sh
@@ -2,28 +2,26 @@
 
 result=0
 
-echo -n "$0: progn with one form... "
 expected='5'
-actual=`echo "(progn (add 2 3))" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(progn (add 2 3))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: progn with two forms... "
 expected='"foo"'
-actual=`echo "(progn (add 2.5 3) \"foo\")" | target/psse 2>/dev/null | tail -1`
+actual=`echo "(progn (add 2.5 3) \"foo\")" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
diff --git a/unit-tests/quote.sh b/unit-tests/quote.sh
index d98e215..78d4ce5 100755
--- a/unit-tests/quote.sh
+++ b/unit-tests/quote.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='Fred'
-actual=`echo "'Fred" | target/psse 2>&1 | tail -1`
+actual=`echo "'Fred" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/quoted-list.sh b/unit-tests/quoted-list.sh
index ade7b2a..f69cd75 100755
--- a/unit-tests/quoted-list.sh
+++ b/unit-tests/quoted-list.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='(123 (4 (5 nil)) Fred)'
-actual=`echo "'(123 (4 (5 ())) Fred)" | target/psse 2>&1 | tail -1`
+actual=`echo "'(123 (4 (5 ())) Fred)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/ratio-addition.sh b/unit-tests/ratio-addition.sh
index 5e5bc7e..ba93c5d 100755
--- a/unit-tests/ratio-addition.sh
+++ b/unit-tests/ratio-addition.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='1/4'
-actual=`echo "(+ 3/14 1/28)" | target/psse 2>&1 | tail -1`
+actual=`echo "(+ 3/14 1/28)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/reverse.sh b/unit-tests/reverse.sh
index a0eb01c..bbc3216 100755
--- a/unit-tests/reverse.sh
+++ b/unit-tests/reverse.sh
@@ -2,33 +2,30 @@
 
 result=0
 
-echo -n "$0: reverse a string... "
 expected='"god yzal eht revo depmuj xof nworb kciuq ehT"'
-actual=`echo '(reverse "The quick brown fox jumped over the lazy dog")' | target/psse 2>&1 | tail -1`
+actual=`echo '(reverse "The quick brown fox jumped over the lazy dog")' | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: reverse a list... "
 expected='(1,024 512 256 128 64 32 16 8 4 2)'
-actual=`echo "(reverse '(2 4 8 16 32 64 128 256 512 1024))" | target/psse 2>&1 | tail -1`
+actual=`echo "(reverse '(2 4 8 16 32 64 128 256 512 1024))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: reverse a symbol... "
 expected='esrever'
-actual=`echo "(reverse 'reverse)" | target/psse 2>&1 | tail -1`
+actual=`echo "(reverse 'reverse)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
@@ -36,8 +33,8 @@ then
     exit 0
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-exit ${result}
+echo ${result}
 
diff --git a/unit-tests/simple-list.sh b/unit-tests/simple-list.sh
index 6fb7e5d..daf3db2 100755
--- a/unit-tests/simple-list.sh
+++ b/unit-tests/simple-list.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected="(1 2 3)"
-actual=`echo "'(1 2 3)" | target/psse 2>&1 | tail -1`
+actual=`echo "'(1 2 3)" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/slurp.sh b/unit-tests/slurp.sh
index 1b0b888..700df15 100755
--- a/unit-tests/slurp.sh
+++ b/unit-tests/slurp.sh
@@ -1,9 +1,9 @@
 #!/bin/bash
 
-tmp=tmp/hi.$$
+tmp=hi.$$
 echo "Hello, there." > ${tmp}
 expected='"Hello, there.'
-actual=`echo "(slurp (open \"${tmp}\"))" | target/psse 2>&1 | tail -2 | head -1`
+actual=`echo "(slurp (open \"${tmp}\"))" | target/psse | tail -2 | head -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/string-cons.sh b/unit-tests/string-cons.sh
index 918dbc6..ad6e3d2 100755
--- a/unit-tests/string-cons.sh
+++ b/unit-tests/string-cons.sh
@@ -2,28 +2,28 @@
 
 result=0
 
-echo -n "$0: We should be able to cons a single character string onto the front of a string... "
+# We should be able to cons a single character string onto the front of a string
 expected='"Test"'
-actual=`echo '(cons "T" "est")' | target/psse 2>/dev/null | tail -1`
+actual=`echo '(cons "T" "est")' | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
-echo -n "$0: But if the first argument has more than one character, we should get a dotted pair... "
+# But if the first argument has more than one character, we should get a dotted pair
 expected='("Test" . "pass")'
-actual=`echo '(cons "Test" "pass")' | target/psse 2>&1 | tail -1`
+actual=`echo '(cons "Test" "pass")' | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    result=`echo "${result} + 1" | bc`
+    result=1
 fi
 
 exit ${result}
diff --git a/unit-tests/string-with-spaces.sh b/unit-tests/string-with-spaces.sh
index 6a424fb..0f0f6d0 100755
--- a/unit-tests/string-with-spaces.sh
+++ b/unit-tests/string-with-spaces.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='"Strings should be able to include spaces (and other stuff)!"'
-actual=`echo ${expected} | target/psse 2>&1 | tail -1`
+actual=`echo ${expected} | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/try.sh b/unit-tests/try.sh
index 43e35ad..a6d529c 100755
--- a/unit-tests/try.sh
+++ b/unit-tests/try.sh
@@ -1,54 +1,45 @@
 #!/bin/bash
 
-result=0
-
-echo -n "$0: if the body of a try errors, the last form in the catch block is returned... "
 expected=':foo'
-actual=`echo "(try ((+ 2 (/ 1 'a))) (:foo))" | target/psse 2>&1 | tail -1`
+actual=`echo "(try ((+ 2 (/ 1 'a))) (:foo))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: if the body of a try errors, the last form in the catch block is evaluated... "
-
 expected='4'
-actual=`echo "(try ((+ 2 (/ 1 'a))) ((+ 2 2)))" | target/psse 2>&1 | tail -1`
+actual=`echo "(try ((+ 2 (/ 1 'a))) ((+ 2 2)))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: body and catch block can optionally be marked with keywords... "
 expected='8'
-actual=`echo "(try (:body (+ 2 (/ 1 'a))) (:catch (* 2 2 2)))" | target/psse 2>&1 | tail -1`
+actual=`echo "(try (:body (+ 2 (/ 1 'a))) (:catch (* 2 2 2)))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
 
-echo -n "$0: the exception is bound to the symbol \`*exception*\` in the catch environment... "
-expected='Exception: "Cannot divide: not a number"'
-actual=`echo "(try (:body (+ 2 (/ 1 'a))) (:catch *exception*))" | target/psse 2>&1 | grep Exception`
+expected=''
+actual=`echo "(try (:body (+ 2 (/ 1 'a))) (:catch *exception*))" | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
     echo "OK"
 else
     echo "Fail: expected '${expected}', got '${actual}'"
-    return=`echo "${return} + 1" | bc`
+    exit 1
 fi
-
-exit ${result}
diff --git a/unit-tests/varargs.sh b/unit-tests/varargs.sh
index 45ff627..27bac3e 100755
--- a/unit-tests/varargs.sh
+++ b/unit-tests/varargs.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='(1 2 3 4 5 6 7 8 9 10)'
-actual=`echo "(set! list (lambda l l))(list 1 2 3 4 5 6 7 8 9 10)" | target/psse 2>&1 | tail -1`
+actual=`echo "(set! list (lambda l l))(list 1 2 3 4 5 6 7 8 9 10)" |target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then
diff --git a/unit-tests/wide-character.sh b/unit-tests/wide-character.sh
index 57dced6..d56544e 100755
--- a/unit-tests/wide-character.sh
+++ b/unit-tests/wide-character.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 expected='"λάμ(β)δα"'
-actual=`echo $expected | target/psse 2>&1 | tail -1`
+actual=`echo $expected | target/psse | tail -1`
 
 if [ "${expected}" = "${actual}" ]
 then