diff --git a/Makefile b/Makefile
index d5ae1e4f..175688ce 100644
--- a/Makefile
+++ b/Makefile
@@ -1,29 +1,65 @@
+# -*- makefile-gmake -*-
 
 .PHONY: all doc dist clean cleaner test install uninstall
 
 all: chibi-scheme
 
-PREFIX=/usr/local
+CC     ?= cc
+PREFIX ?= /usr/local
 BINDIR=$(PREFIX)/bin
 LIBDIR=$(PREFIX)/lib
-INCDIR=$(PREFIX)/include/chibi-scheme
-MODDIR=$(PREFIX)/share/chibi-scheme
+INCDIR=$(PREFIX)/include/chibi
+MODDIR=$(PREFIX)/share/chibi
 
-LDFLAGS=-lm #-lgc -L/opt/local/lib
+ifndef PLATFORM
+ifeq ($(shell uname),Darwin)
+PLATFORM=macosx
+else
+PLATFORM=unix
+endif
+endif
 
-CFLAGS=-Wall -O2 -g #-I/opt/local/include #-save-temps
+ifeq ($(PLATFORM),macosx)
+SO  = .dylib
+EXE =
+CLIBFLAGS = -dynamiclib
+else ifeq ($(PLATFORM),mingw)
+SO  = .dll
+EXE = .exe
+CLIBFLAGS = -fPIC shared
+else
+SO  = .so
+EXE =
+CLIBFLAGS = -fPIC -shared
+endif
 
-sexp.o: sexp.c gc.c sexp.h config.h Makefile
-	gcc -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+ifdef USE_BOEHM
+GCLDFLAGS := -lgc
+else
+GCLDFLAGS :=
+endif
 
-eval.o: eval.c debug.c opcodes.c eval.h sexp.h config.h Makefile
-	gcc -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+LDFLAGS  := $(LDFLAGS) -lm
+CPPFLAGS := $(CPPFLAGS) -Iinclude
+CFLAGS   := $(CFLAGS) -Wall -O2 -g
 
-main.o: main.c eval.c debug.c opcodes.c eval.h sexp.h config.h Makefile
-	gcc -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+sexp.o: sexp.c gc.c include/chibi/sexp.h include/chibi/config.h Makefile
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-chibi-scheme: main.o sexp.o
-	gcc $(CFLAGS) $(LDFLAGS) -o $@ $^
+eval.o: eval.c debug.c opcodes.c include/chibi/eval.h include/chibi/sexp.h include/chibi/config.h Makefile
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+
+main.o: main.c eval.c debug.c opcodes.c include/chibi/eval.h include/chibi/sexp.h include/chibi/config.h Makefile
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+
+libchibi-scheme$(SO): eval.o sexp.o
+	$(CC) -dynamiclib -o $@ $^
+
+chibi-scheme$(EXE): main.o libchibi-scheme$(SO)
+	$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ $< $(LDFLAGS) $(GCLDFLAGS) -L. -lchibi-scheme
+
+chibi-scheme-static$(EXE): main.o eval.o sexp.o
+	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS) $(GCLDFLAGS)
 
 clean:
 	rm -f *.o *.i *.s
diff --git a/eval.c b/eval.c
index e7515c46..50e9efb5 100644
--- a/eval.c
+++ b/eval.c
@@ -2,7 +2,7 @@
 /*  Copyright (c) 2009 Alex Shinn.  All rights reserved. */
 /*  BSD-style license: http://synthcode.com/license.txt  */
 
-#include "eval.h"
+#include "chibi/eval.h"
 
 /************************************************************************/
 
@@ -248,7 +248,7 @@ static sexp sexp_make_lit(sexp ctx, sexp value) {
 
 #define SEXP_STACK_SIZE (sexp_sizeof(stack)+sizeof(sexp)*INIT_STACK_SIZE)
 
-static sexp sexp_make_context(sexp ctx, sexp stack, sexp env) {
+sexp sexp_make_context(sexp ctx, sexp stack, sexp env) {
   sexp_gc_var(ctx, res, save_res);
   if (ctx) sexp_gc_preserve(ctx, res, save_res);
   res = sexp_alloc_type(ctx, context, SEXP_CONTEXT);
@@ -279,7 +279,7 @@ static sexp sexp_make_context(sexp ctx, sexp stack, sexp env) {
   return res;
 }
 
-static sexp sexp_make_child_context(sexp context, sexp lambda) {
+sexp sexp_make_child_context(sexp context, sexp lambda) {
   sexp ctx = sexp_make_context(context,
                                sexp_context_stack(context),
                                sexp_context_env(context));
@@ -582,7 +582,7 @@ static sexp analyze_bind_syntax (sexp ls, sexp eval_ctx, sexp bind_ctx) {
            && sexp_nullp(sexp_cddar(ls)))) {
       res = sexp_compile_error(eval_ctx, "bad syntax binding", sexp_car(ls));
     } else {
-      proc = eval_in_context(eval_ctx, sexp_cadar(ls));
+      proc = sexp_eval(eval_ctx, sexp_cadar(ls));
       if (sexp_exceptionp(proc)) {
         res = proc;
         break;
@@ -697,9 +697,9 @@ static sexp analyze (sexp ctx, sexp object) {
           tmp = sexp_cons(ctx, sexp_macro_env(op), SEXP_NULL);
           tmp = sexp_cons(ctx, sexp_context_env(ctx), tmp);
           tmp = sexp_cons(ctx, x, tmp);
-          x = apply(sexp_make_child_context(ctx, sexp_context_lambda(ctx)),
-                    sexp_macro_proc(op),
-                    tmp);
+          x = sexp_apply(sexp_make_child_context(ctx, sexp_context_lambda(ctx)),
+                         sexp_macro_proc(op),
+                         tmp);
           /* if (in_repl_p) sexp_debug("     => ", x, ctx); */
           goto loop;
         } else if (sexp_opcodep(op)) {
@@ -1216,7 +1216,7 @@ static sexp_uint_t sexp_restore_stack(sexp saved, sexp *current) {
                                      goto call_error_handler;} \
                                 while (0)
 
-sexp vm (sexp ctx, sexp proc) {
+sexp sexp_vm (sexp ctx, sexp proc) {
   sexp bc = sexp_procedure_code(proc), cp = sexp_procedure_vars(proc);
   sexp env = sexp_context_env(ctx),
     *stack = sexp_stack_data(sexp_context_stack(ctx));
@@ -1414,7 +1414,7 @@ sexp vm (sexp ctx, sexp proc) {
     break;
   case OP_EVAL:
     sexp_context_top(ctx) = top;
-    _ARG1 = eval_in_context(ctx, _ARG1);
+    _ARG1 = sexp_eval(ctx, _ARG1);
     sexp_check_exception();
     break;
   case OP_JUMP_UNLESS:
@@ -1830,7 +1830,7 @@ static sexp sexp_close_port (sexp ctx, sexp port) {
   return SEXP_VOID;
 }
 
-static void sexp_warn_undefs (sexp from, sexp to, sexp out) {
+void sexp_warn_undefs (sexp from, sexp to, sexp out) {
   sexp x;
   for (x=from; sexp_pairp(x) && x!=to; x=sexp_cdr(x))
     if (sexp_cdar(x) == SEXP_UNDEF) {
@@ -1862,7 +1862,7 @@ sexp sexp_load (sexp ctx, sexp source, sexp env) {
     res = in;
   } else {
     while ((x=sexp_read(ctx, in)) != (sexp) SEXP_EOF) {
-      res = eval_in_context(ctx2, x);
+      res = sexp_eval(ctx2, x);
       if (sexp_exceptionp(res))
         break;
     }
@@ -2013,23 +2013,26 @@ static sexp sexp_make_null_env (sexp ctx, sexp version) {
 
 static sexp sexp_make_standard_env (sexp ctx, sexp version) {
   sexp_uint_t i;
-  sexp cell, sym;
+  sexp ctx2, cell, sym, perr_cell, err_cell;
   sexp_gc_var(ctx, e, s_e);
   sexp_gc_var(ctx, op, s_op);
+  sexp_gc_var(ctx, tmp, s_tmp);
+  sexp_gc_var(ctx, err_handler, s_err);
   sexp_gc_preserve(ctx, e, s_e);
   sexp_gc_preserve(ctx, op, s_op);
+  sexp_gc_preserve(ctx, tmp, s_tmp);
+  sexp_gc_preserve(ctx, err_handler, s_err);
   e = sexp_make_null_env(ctx, version);
   for (i=0; i<(sizeof(opcodes)/sizeof(opcodes[0])); i++) {
-    /* op = &opcodes[i]; */
     op = sexp_copy_opcode(ctx, &opcodes[i]);
     if (sexp_opcode_opt_param_p(op) && sexp_opcode_default(op)) {
-      /* op = sexp_copy_opcode(ctx, op); */
       sym = sexp_intern(ctx, (char*)sexp_opcode_default(op));
       cell = env_cell_create(ctx, e, sym, SEXP_VOID);
       sexp_opcode_default(op) = cell;
     }
     env_define(ctx, e, sexp_intern(ctx, sexp_opcode_name(op)), op);
   }
+  /* add io port and interaction env parameters */
   env_define(ctx, e, the_cur_in_symbol,
              sexp_make_input_port(ctx, stdin, SEXP_FALSE));
   env_define(ctx, e, the_cur_out_symbol,
@@ -2037,13 +2040,35 @@ static sexp sexp_make_standard_env (sexp ctx, sexp version) {
   env_define(ctx, e, the_cur_err_symbol,
              sexp_make_output_port(ctx, stderr, SEXP_FALSE));
   env_define(ctx, e, the_interaction_env_symbol, e);
+  /* add default exception handler */
+  err_cell = env_cell(e, the_cur_err_symbol);
+  perr_cell = env_cell(e, sexp_intern(ctx, "print-exception"));
+  ctx2 = sexp_make_context(ctx, sexp_context_stack(ctx), e);
+  sexp_context_tailp(ctx2) = 0;
+  if (err_cell && perr_cell && sexp_opcodep(sexp_cdr(perr_cell))) {
+    emit(ctx2, OP_GLOBAL_KNOWN_REF);
+    emit_word(ctx2, (sexp_uint_t)err_cell);
+    emit(ctx2, OP_LOCAL_REF);
+    emit_word(ctx2, 0);
+    emit(ctx2, OP_FCALL2);
+    emit_word(ctx2, (sexp_uint_t)sexp_opcode_data(sexp_cdr(perr_cell)));
+  }
+  emit_push(ctx2, SEXP_VOID);
+  emit(ctx2, OP_DONE);
+  tmp = sexp_make_vector(ctx2, 0, SEXP_VOID);
+  err_handler = sexp_make_procedure(ctx2,
+                                    sexp_make_integer(0),
+                                    sexp_make_integer(0),
+                                    finalize_bytecode(ctx2),
+                                    tmp);
+  env_define(ctx2, e, the_err_handler_symbol, err_handler);
   sexp_gc_release(ctx, e, s_e);
   return e;
 }
 
 /************************** eval interface ****************************/
 
-sexp apply (sexp ctx, sexp proc, sexp args) {
+sexp sexp_apply (sexp ctx, sexp proc, sexp args) {
   sexp ls, *stack = sexp_stack_data(sexp_context_stack(ctx));
   sexp_sint_t top = sexp_context_top(ctx), offset;
   offset = top + sexp_unbox_integer(sexp_length(ctx, args));
@@ -2055,10 +2080,10 @@ sexp apply (sexp ctx, sexp proc, sexp args) {
   stack[top++] = sexp_make_integer(sexp_bytecode_data(final_resumer));
   stack[top++] = sexp_make_vector(ctx, 0, SEXP_VOID);
   stack[top++] = sexp_make_integer(0);
-  return vm(ctx, proc);
+  return sexp_vm(ctx, proc);
 }
 
-sexp compile (sexp ctx, sexp x) {
+sexp sexp_compile (sexp ctx, sexp x) {
   sexp_gc_var(ctx, ast, s_ast);
   sexp_gc_var(ctx, ctx2, s_ctx2);
   sexp_gc_var(ctx, vec, s_vec);
@@ -2084,11 +2109,11 @@ sexp compile (sexp ctx, sexp x) {
   return res;
 }
 
-sexp eval_in_context (sexp ctx, sexp obj) {
+sexp sexp_eval (sexp ctx, sexp obj) {
   sexp res;
   sexp_gc_var(ctx, thunk, s_thunk);
   sexp_gc_preserve(ctx, thunk, s_thunk);
-  thunk = compile(ctx, obj);
+  thunk = sexp_compile(ctx, obj);
   if (sexp_exceptionp(thunk)) {
     sexp_print_exception(ctx, thunk,
                          env_global_ref(sexp_context_env(ctx),
@@ -2096,19 +2121,23 @@ sexp eval_in_context (sexp ctx, sexp obj) {
                                         SEXP_FALSE));
     res = thunk;
   } else {
-    res = apply(ctx, thunk, SEXP_NULL);
+    res = sexp_apply(ctx, thunk, SEXP_NULL);
   }
   sexp_gc_release(ctx, thunk, s_thunk);
   return res;
 }
 
-sexp eval (sexp obj, sexp env) {
-  sexp ctx = sexp_make_context(NULL, NULL, NULL);
-  sexp_context_env(ctx) = env;
-  return eval_in_context(ctx, obj);
+sexp sexp_eval_string (sexp ctx, char *str) {
+  sexp res;
+  sexp_gc_var(ctx, obj, s_obj);
+  sexp_gc_preserve(ctx, obj, s_obj);
+  obj = sexp_read_from_string(ctx, str);
+  res = sexp_eval(ctx, obj);
+  sexp_gc_release(ctx, obj, s_obj);
+  return res;
 }
 
-void scheme_init () {
+void sexp_scheme_init () {
   sexp ctx;
   if (! scheme_initialized_p) {
     scheme_initialized_p = 1;
diff --git a/gc.c b/gc.c
index f881ecd6..37444e04 100644
--- a/gc.c
+++ b/gc.c
@@ -2,7 +2,7 @@
 /*  Copyright (c) 2009 Alex Shinn.  All rights reserved. */
 /*  BSD-style license: http://synthcode.com/license.txt  */
 
-#include "sexp.h"
+#include "chibi/sexp.h"
 
 #define SEXP_INITIAL_HEAP_SIZE (2*1024*1024)
 #define SEXP_MAXIMUM_HEAP_SIZE 0
diff --git a/config.h b/include/chibi/config.h
similarity index 93%
rename from config.h
rename to include/chibi/config.h
index bb14e68b..07b993eb 100644
--- a/config.h
+++ b/include/chibi/config.h
@@ -14,7 +14,7 @@
 /* uncomment this if you only want fixnum support */
 /* #define USE_FLONUMS 0 */
 
-/* uncomment this if you want immediate flonums (experimental) */
+/* uncomment this if you want immediate flonums */
 /* #define USE_IMMEDIATE_FLONUMS 1 */
 
 /* uncomment this if you don't need extended math operations */
@@ -32,8 +32,8 @@
 /* uncomment this to disable string ports */
 /* #define USE_STRING_STREAMS 0 */
 
-/* uncomment this to disable stack checks */
-/* #define USE_CHECK_STACK 0 */
+/* uncomment this to enable stack overflow checks */
+/* #define USE_CHECK_STACK 1 */
 
 /* uncomment this to enable debugging utilities */
 /* #define USE_DEBUG 1 */
@@ -101,6 +101,6 @@
 #endif
 
 #ifndef USE_CHECK_STACK
-#define USE_CHECK_STACK 1
+#define USE_CHECK_STACK 0
 #endif
 
diff --git a/eval.h b/include/chibi/eval.h
similarity index 84%
rename from eval.h
rename to include/chibi/eval.h
index ee870110..65fc66a1 100644
--- a/eval.h
+++ b/include/chibi/eval.h
@@ -14,8 +14,6 @@
 
 #define sexp_init_file "init.scm"
 
-#define sexp_debug(msg, obj, ctx) (sexp_write_string(msg,env_global_ref(sexp_context_env(ctx), the_cur_err_symbol, SEXP_FALSE)), sexp_write(obj, env_global_ref(sexp_context_env(ctx), the_cur_err_symbol, SEXP_FALSE)), sexp_write_char('\n',env_global_ref(sexp_context_env(ctx), the_cur_err_symbol, SEXP_FALSE)))
-
 /* procedure types */
 typedef sexp (*sexp_proc0) ();
 typedef sexp (*sexp_proc1) (sexp);
@@ -130,9 +128,13 @@ enum opcode_names {
 
 /**************************** prototypes ******************************/
 
-sexp apply(sexp proc, sexp args, sexp context);
-sexp eval_in_context(sexp expr, sexp context);
-sexp eval(sexp expr, sexp env);
+SEXP_API void sexp_scheme_init();
+SEXP_API sexp sexp_apply(sexp context, sexp proc, sexp args);
+SEXP_API sexp sexp_eval(sexp context, sexp obj);
+SEXP_API sexp sexp_eval_string(sexp context, char *str);
+SEXP_API sexp sexp_load(sexp context, sexp expr, sexp env);
+SEXP_API sexp sexp_make_context(sexp context, sexp stack, sexp env);
+SEXP_API void sexp_warn_undefs (sexp from, sexp to, sexp out);
 
 #endif /* ! SEXP_EVAL_H */
 
diff --git a/sexp.h b/include/chibi/sexp.h
similarity index 89%
rename from sexp.h
rename to include/chibi/sexp.h
index 94f6c68b..c4979f02 100644
--- a/sexp.h
+++ b/include/chibi/sexp.h
@@ -16,6 +16,10 @@
 #include <sys/types.h>
 #include <math.h>
 
+#ifndef SEXP_API
+#define SEXP_API extern
+#endif
+
 /* tagging system
  *   bits end in  00:  pointer
  *                01:  fixnum
@@ -511,43 +515,43 @@ sexp sexp_make_flonum(sexp ctx, double f);
 #define sexp_scanf(p, ...) (fscanf(sexp_port_stream(p), __VA_ARGS__))
 #define sexp_flush(p) (fflush(sexp_port_stream(p)))
 
-sexp sexp_alloc_tagged(sexp ctx, size_t size, sexp_uint_t tag);
-sexp sexp_cons(sexp ctx, sexp head, sexp tail);
-sexp sexp_list2(sexp ctx, sexp a, sexp b);
-sexp sexp_equalp (sexp ctx, sexp a, sexp b);
-sexp sexp_listp(sexp ctx, sexp obj);
-sexp sexp_reverse(sexp ctx, sexp ls);
-sexp sexp_nreverse(sexp ctx, sexp ls);
-sexp sexp_append2(sexp ctx, sexp a, sexp b);
-sexp sexp_memq(sexp ctx, sexp x, sexp ls);
-sexp sexp_assq(sexp ctx, sexp x, sexp ls);
-sexp sexp_length(sexp ctx, sexp ls);
-sexp sexp_c_string(sexp ctx, char *str, sexp_sint_t slen);
-sexp sexp_make_string(sexp ctx, sexp len, sexp ch);
-sexp sexp_substring (sexp ctx, sexp str, sexp start, sexp end);
-sexp sexp_intern(sexp ctx, char *str);
-sexp sexp_string_to_symbol(sexp ctx, sexp str);
-sexp sexp_make_vector(sexp ctx, sexp len, sexp dflt);
-sexp sexp_list_to_vector(sexp ctx, sexp ls);
-sexp sexp_vector(sexp ctx, int count, ...);
-void sexp_write(sexp obj, sexp out);
-sexp sexp_read_string(sexp ctx, sexp in);
-sexp sexp_read_symbol(sexp ctx, sexp in, int init, int internp);
-sexp sexp_read_number(sexp ctx, sexp in, int base);
-sexp sexp_read_raw(sexp ctx, sexp in);
-sexp sexp_read(sexp ctx, sexp in);
-sexp sexp_read_from_string(sexp ctx, char *str);
-sexp sexp_make_input_port(sexp ctx, FILE* in, sexp name);
-sexp sexp_make_output_port(sexp ctx, FILE* out, sexp name);
-sexp sexp_make_input_string_port(sexp ctx, sexp str);
-sexp sexp_make_output_string_port(sexp ctx);
-sexp sexp_get_output_string(sexp ctx, sexp port);
-sexp sexp_make_exception(sexp ctx, sexp kind, sexp message, sexp irritants, sexp procedure, sexp file, sexp line);
-sexp sexp_user_exception (sexp ctx, sexp self, char *message, sexp obj);
-sexp sexp_type_exception (sexp ctx, char *message, sexp obj);
-sexp sexp_range_exception (sexp ctx, sexp obj, sexp start, sexp end);
-sexp sexp_print_exception(sexp ctx, sexp exn, sexp out);
-void sexp_init();
+SEXP_API sexp sexp_alloc_tagged(sexp ctx, size_t size, sexp_uint_t tag);
+SEXP_API sexp sexp_cons(sexp ctx, sexp head, sexp tail);
+SEXP_API sexp sexp_list2(sexp ctx, sexp a, sexp b);
+SEXP_API sexp sexp_equalp (sexp ctx, sexp a, sexp b);
+SEXP_API sexp sexp_listp(sexp ctx, sexp obj);
+SEXP_API sexp sexp_reverse(sexp ctx, sexp ls);
+SEXP_API sexp sexp_nreverse(sexp ctx, sexp ls);
+SEXP_API sexp sexp_append2(sexp ctx, sexp a, sexp b);
+SEXP_API sexp sexp_memq(sexp ctx, sexp x, sexp ls);
+SEXP_API sexp sexp_assq(sexp ctx, sexp x, sexp ls);
+SEXP_API sexp sexp_length(sexp ctx, sexp ls);
+SEXP_API sexp sexp_c_string(sexp ctx, char *str, sexp_sint_t slen);
+SEXP_API sexp sexp_make_string(sexp ctx, sexp len, sexp ch);
+SEXP_API sexp sexp_substring (sexp ctx, sexp str, sexp start, sexp end);
+SEXP_API sexp sexp_intern(sexp ctx, char *str);
+SEXP_API sexp sexp_string_to_symbol(sexp ctx, sexp str);
+SEXP_API sexp sexp_make_vector(sexp ctx, sexp len, sexp dflt);
+SEXP_API sexp sexp_list_to_vector(sexp ctx, sexp ls);
+SEXP_API sexp sexp_vector(sexp ctx, int count, ...);
+SEXP_API void sexp_write(sexp obj, sexp out);
+SEXP_API sexp sexp_read_string(sexp ctx, sexp in);
+SEXP_API sexp sexp_read_symbol(sexp ctx, sexp in, int init, int internp);
+SEXP_API sexp sexp_read_number(sexp ctx, sexp in, int base);
+SEXP_API sexp sexp_read_raw(sexp ctx, sexp in);
+SEXP_API sexp sexp_read(sexp ctx, sexp in);
+SEXP_API sexp sexp_read_from_string(sexp ctx, char *str);
+SEXP_API sexp sexp_make_input_port(sexp ctx, FILE* in, sexp name);
+SEXP_API sexp sexp_make_output_port(sexp ctx, FILE* out, sexp name);
+SEXP_API sexp sexp_make_input_string_port(sexp ctx, sexp str);
+SEXP_API sexp sexp_make_output_string_port(sexp ctx);
+SEXP_API sexp sexp_get_output_string(sexp ctx, sexp port);
+SEXP_API sexp sexp_make_exception(sexp ctx, sexp kind, sexp message, sexp irritants, sexp procedure, sexp file, sexp line);
+SEXP_API sexp sexp_user_exception (sexp ctx, sexp self, char *message, sexp obj);
+SEXP_API sexp sexp_type_exception (sexp ctx, char *message, sexp obj);
+SEXP_API sexp sexp_range_exception (sexp ctx, sexp obj, sexp start, sexp end);
+SEXP_API sexp sexp_print_exception(sexp ctx, sexp exn, sexp out);
+SEXP_API void sexp_init();
 
 #endif /* ! SEXP_H */
 
diff --git a/main.c b/main.c
index 66a6b85b..1beb9889 100644
--- a/main.c
+++ b/main.c
@@ -1,5 +1,8 @@
+/* main.c -- chibi-scheme command-line app using        */
+/* Copyright (c) 2009 Alex Shinn.  All rights reserved. */
+/* BSD-style license: http://synthcode.com/license.txt  */
 
-#include "eval.c"
+#include "chibi/eval.h"
 
 void repl (sexp ctx) {
   sexp tmp, res, env, in, out, err;
@@ -7,9 +10,9 @@ void repl (sexp ctx) {
   sexp_gc_preserve(ctx, obj, s_obj);
   env = sexp_context_env(ctx);
   sexp_context_tracep(ctx) = 1;
-  in = env_global_ref(env, the_cur_in_symbol, SEXP_FALSE);
-  out = env_global_ref(env, the_cur_out_symbol, SEXP_FALSE);
-  err = env_global_ref(env, the_cur_err_symbol, SEXP_FALSE);
+  in = sexp_eval_string(ctx, "(current-input-port)");
+  out = sexp_eval_string(ctx, "(current-output-port)");
+  err = sexp_eval_string(ctx, "(current-error-port)");
   while (1) {
     sexp_write_string("> ", out);
     sexp_flush(out);
@@ -21,7 +24,7 @@ void repl (sexp ctx) {
     } else {
       tmp = sexp_env_bindings(env);
       sexp_context_top(ctx) = 0;
-      res = eval_in_context(ctx, obj);
+      res = sexp_eval(ctx, obj);
 #if USE_WARN_UNDEFS
       sexp_warn_undefs(sexp_env_bindings(env), tmp, err);
 #endif
@@ -35,34 +38,14 @@ void repl (sexp ctx) {
 }
 
 void run_main (int argc, char **argv) {
-  sexp env, out=NULL, res, ctx, perr_cell, err_cell, err_handler;
+  sexp env, out=NULL, res, ctx;
   sexp_uint_t i, quit=0, init_loaded=0;
   sexp_gc_var(ctx, str, s_str);
 
   ctx = sexp_make_context(NULL, NULL, NULL);
   sexp_gc_preserve(ctx, str, s_str);
   env = sexp_context_env(ctx);
-  env_define(ctx, env, the_interaction_env_symbol, env);
-  out = env_global_ref(env, the_cur_out_symbol, SEXP_FALSE);
-  err_cell = env_cell(env, the_cur_err_symbol);
-  perr_cell = env_cell(env, sexp_intern(ctx, "print-exception"));
-  sexp_context_tailp(ctx) = 0;
-  if (err_cell && perr_cell && sexp_opcodep(sexp_cdr(perr_cell))) {
-    emit(ctx, OP_GLOBAL_KNOWN_REF);
-    emit_word(ctx, (sexp_uint_t)err_cell);
-    emit(ctx, OP_LOCAL_REF);
-    emit_word(ctx, 0);
-    emit(ctx, OP_FCALL2);
-    emit_word(ctx, (sexp_uint_t)sexp_opcode_data(sexp_cdr(perr_cell)));
-  }
-  emit_push(ctx, SEXP_VOID);
-  emit(ctx, OP_DONE);
-  err_handler = sexp_make_procedure(ctx,
-                                    sexp_make_integer(0),
-                                    sexp_make_integer(0),
-                                    finalize_bytecode(ctx),
-                                    sexp_make_vector(ctx, 0, SEXP_VOID));
-  env_define(ctx, env, the_err_handler_symbol, err_handler);
+  out = sexp_eval_string(ctx, "(current-output-port)");
 
   /* parse options */
   for (i=1; i < argc && argv[i][0] == '-'; i++) {
@@ -74,7 +57,7 @@ void run_main (int argc, char **argv) {
         sexp_load(ctx, str=sexp_c_string(ctx, sexp_init_file, -1), env);
       res = sexp_read_from_string(ctx, argv[i+1]);
       if (! sexp_exceptionp(res))
-        res = eval_in_context(ctx, res);
+        res = sexp_eval(ctx, res);
       if (sexp_exceptionp(res)) {
         sexp_print_exception(ctx, res, out);
       } else if (argv[i][1] == 'p') {
@@ -112,7 +95,7 @@ void run_main (int argc, char **argv) {
 }
 
 int main (int argc, char **argv) {
-  scheme_init();
+  sexp_scheme_init();
   run_main(argc, argv);
   return 0;
 }
diff --git a/sexp.c b/sexp.c
index ed8071ae..775f64c8 100644
--- a/sexp.c
+++ b/sexp.c
@@ -2,7 +2,8 @@
 /*  Copyright (c) 2009 Alex Shinn.  All rights reserved. */
 /*  BSD-style license: http://synthcode.com/license.txt  */
 
-#include "sexp.h"
+#define SEXP_API
+#include "chibi/sexp.h"
 
 /* optional huffman-compressed immediate symbols */
 #if USE_HUFF_SYMS