diff --git a/src/env.c b/src/env.c
index 590f0af..7ccb3b8 100644
--- a/src/env.c
+++ b/src/env.c
@@ -142,6 +142,40 @@ void deleteEnv(struct Environment *e)
     e->objects = NULL;
 }
 
+const char *codes[] = {
+    // Exponentiate a^b
+    "(def exp (fn (a b) "
+      "(if (= b 0)"
+        "1"
+        "(* a (exp a (- b 1)))"
+      ")"
+    "))",
+
+    // Square a
+    "(def sq (fn (a) (exp a 2)))",
+
+    // Cube a
+    "(def cube (fn (a) (exp a 3)))",
+
+    // Return the larger of the two
+    "(def max (fn (a b) (if (> a b) a b)))",
+
+    // Return the smaller of the two
+    "(def min (fn (a b) (if (< a b) a b)))",
+
+    // Arbitrary recursion tester
+    "(def ad (fn (a) (if (> a 10) a (ad (* 10 a) ))))",
+
+    // A demo tip calculator
+    "(def spent (fn (a) \
+      (cat \"Tip: $\" \"\" \"\" (/ a 5) \".\" \
+        (/ (* 100 (% a 5)) 5) \
+      ) \
+     ))",
+
+    NULL
+};
+
 struct Environment defaultEnv()
 {
     struct Environment e;
@@ -161,14 +195,10 @@ struct Environment defaultEnv()
     addFunc("len", &len, &e);
     addFunc("cat", &catObjects, &e);
 
-    parseEval("(def max (fn (a b) (if (> a b) a b)))", &e);
-    parseEval("(def min (fn (a b) (if (< a b) a b)))", &e);
-    parseEval("(def ad (fn (a) (if (> a 10) a (ad (* 10 a) ))))", &e);
-    parseEval("(def spent (fn (a) \
-                (cat \"Tip: $\" \"\" \"\" (/ a 5) \".\" \
-                  (/ (* 100 (% a 5)) 5) \
-                ) \
-               ))", &e);
+    int i = 0;
+    while(codes[i]) {
+        parseEval(codes[i++], &e);
+    }
 
     return e;
 }
diff --git a/src/object.h b/src/object.h
index 1b3a78d..86bd048 100644
--- a/src/object.h
+++ b/src/object.h
@@ -32,7 +32,9 @@ enum errorCode {
     DID_NOT_FIND_SYMBOL,
     BAD_TYPE,
     UNEXPECTED_FORM,
-    LISTS_NOT_SAME_SIZE
+    LISTS_NOT_SAME_SIZE,
+    SYMBOLS_CANT_START_WITH_DIGITS,
+    UNSUPPORTED_NUMBER_TYPE
 };
 
 //#ifdef STANDALONE
@@ -50,7 +52,9 @@ static const char *errorText[] = {
     "DID_NOT_FIND_SYMBOL",
     "BAD_TYPE",
     "UNEXPECTED_FORM",
-    "LISTS_NOT_SAME_SIZE"
+    "LISTS_NOT_SAME_SIZE",
+    "SYMBOLS_CANT_START_WITH_DIGITS",
+    "UNSUPPORTED_NUMBER_TYPE"
 };
 //#endif
 
diff --git a/src/pebblisp.c b/src/pebblisp.c
index 5e0391d..2f7d7b7 100644
--- a/src/pebblisp.c
+++ b/src/pebblisp.c
@@ -9,9 +9,9 @@
 #define printf(...) APP_LOG(APP_LOG_LEVEL_DEBUG, __VA_ARGS__)
 #endif
 
-Object evalDefArgs(const Object *arg_forms, struct Environment *env)
+Object evalDefArgs(const Object *argForms, struct Environment *env)
 {
-    const Object *newSymbol = arg_forms;
+    const Object *newSymbol = argForms;
     const char *name = newSymbol->name;
 
     const Object newValue = eval(newSymbol->forward, env);
@@ -21,26 +21,26 @@ Object evalDefArgs(const Object *arg_forms, struct Environment *env)
     return *newSymbol;
 }
 
-Object evalIfArgs(const Object *arg_forms, struct Environment *env)
+Object evalIfArgs(const Object *argForms, struct Environment *env)
 {
-    return eval(arg_forms, env).number? 
-            eval(arg_forms->forward, env) : 
-            eval(arg_forms->forward->forward, env);
+    return eval(argForms, env).number?
+            eval(argForms->forward, env) :
+            eval(argForms->forward->forward, env);
 }
 
-Object evalLambdaArgs(const Object *arg_forms)
+Object evalLambdaArgs(const Object *argForms)
 {
                          // params               // body
-    return constructLambda(arg_forms, arg_forms? arg_forms->forward : NULL);
+    return constructLambda(argForms, argForms? argForms->forward : NULL);
 }
 
-Object evalMapArgs(const Object *arg_forms, struct Environment *env)
+Object evalMapArgs(const Object *argForms, struct Environment *env)
 {
-    if(!arg_forms)
+    if(!argForms)
         return errorObject(NULL_MAP_ARGS);
     
-    const Object lambda = eval(arg_forms, env);
-    const Object *inputList = arg_forms->forward;
+    const Object lambda = eval(argForms, env);
+    const Object *inputList = argForms->forward;
 
     if(lambda.type != TYPE_LAMBDA || inputList->type != TYPE_LIST)
         return errorObject(BAD_TYPE);
@@ -114,12 +114,11 @@ Object eval(const Object *obj, struct Environment *env)
             Object *first_form = obj->list;
 
             { // Try to eval built-ins
-                const Object built_in =
+                const Object builtIn =
                         evalBuiltIns(first_form, first_form->forward, env);
                 
-                // deleteList(obj); // Decreases indirectly lost memory, but fails on Pebble
-                if(built_in.type != TYPE_ERROR) {
-                    return built_in;
+                if(builtIn.type != TYPE_ERROR) {
+                    return builtIn;
                 }
             }
 
@@ -138,7 +137,6 @@ Object eval(const Object *obj, struct Environment *env)
                     cleanObject(&rest[i]);
                 }
 
-                // deleteList(obj); // Decreases indirectly lost memory, but fails on Pebble
                 return func_eval;
 
             } else if (first_eval.type == TYPE_LAMBDA) {
@@ -242,7 +240,7 @@ Object basicOp(const Object *obj1, const Object *obj2, const char op,
         }
         return newList;
 
-    } else { // 2 lists
+    } else { // 2 lists with the op applied to matching indices of both lists
         if(listLength(obj1) == listLength(obj2)) {
             Object newList = listObject();
             FOR_POINTERS_IN_LISTS(obj1, obj2) {
@@ -327,20 +325,32 @@ Result readSeq(struct Slice *tokens)
     }
 }
 
-Object parseAtom(struct Slice *s)
+Object parseDecimal(struct Slice *s)
 {
-    if(isDigit(s->text[0])) {
         int num = 0;
         for(int i = 0; i < s->length; i++) {
+            if(!isDigit(s->text[i])) {
+                return errorObject(SYMBOLS_CANT_START_WITH_DIGITS);
+            }
             num *= 10;
             num += s->text[i] - '0';
         }
         return numberObject(num);
+}
 
-    } else if (s->text[0] == 'T' && s->length == 1) {
+Object parseAtom(struct Slice *s)
+{
+    if(isDigit(s->text[0])) {
+        if(s->text[0] != '0' || s->length == 1)
+            return parseDecimal(s);
+        else {
+            return errorObject(UNSUPPORTED_NUMBER_TYPE);
+        }
+
+    } else if (s->length == 1 && (s->text[0] == 'T' || s->text[0] == 't')) {
         return boolObject(1);
 
-    } else if (s->text[0] == 'F' && s->length == 1) {
+    } else if (s->length == 1 && (s->text[0] == 'F' || s->text[0] == 'f')) {
         return boolObject(0);
 
     } else if (s->text[0] == '"') {
diff --git a/src/tests.sh b/src/tests.sh
index ac7d019..7871e87 100755
--- a/src/tests.sh
+++ b/src/tests.sh
@@ -82,10 +82,14 @@ check "CatNums" "(cat \"There are \" (+ 2 3) \" kitties\")" "There are 5 kitties
 check "ImplicitCat" "(+ \"There are \" (* 5 4) \" bonks\")" "There are 20 bonks"
 # Not recommended
 check "CatAssocLeft" "(+ 10 20 \" rascals\")" "30 rascals"
-echo""
+echo ""
 check "EvalElems" "((* 10 10) 7)" "( 100 7 )"
 check "Duplicate" "(def dupe (fn (a) (a a a))) (dupe (*10 10))" "( 100 100 100 )"
-echo""
+echo ""
+check "Squaring" "(sq 9876)" "97535376"
+check "Cubing" "(cube 81)" "531441"
+check "Exponent" "(exp 9 9)" "387420489"
+echo ""
 
 if [ "$FAILS" -ne "0" ]; then
         echo "$FAILS Tests Failed"