diff --git a/Makefile b/Makefile
index cb4c9d7b..125d5dd3 100644
--- a/Makefile
+++ b/Makefile
@@ -57,6 +57,10 @@ all: picrin
 debug: CFLAGS += -O0 -g
 debug: picrin
 
+tiny-picrin: CFLAGS += -O0 -g -DPIC_USE_LIBRARY=0
+tiny-picrin: $(LIBPICRIN_OBJS) src/tiny-main.o
+	$(CC) $(CFLAGS) -o $@ $(LIBPICRIN_OBJS) src/tiny-main.o $(LDFLAGS)
+
 include $(sort $(wildcard contrib/*/nitro.mk))
 
 picrin: CFLAGS += $(CONTRIB_DEFS)
@@ -74,7 +78,7 @@ src/init_contrib.c:
 # 	$(CC) -shared $(CFLAGS) -o $@ $(LIBPICRIN_OBJS) $(LDFLAGS)
 
 lib/ext/boot.c: piclib/boot.scm piclib/library.scm
-	cat piclib/boot.scm piclib/library.scm | bin/picrin-bootstrap tools/mkboot.scm > lib/ext/boot.c
+	bin/picrin-bootstrap tools/mkboot.scm > lib/ext/boot.c
 
 $(LIBPICRIN_OBJS) $(PICRIN_OBJS) $(CONTRIB_OBJS): lib/include/picrin.h lib/include/picrin/*.h lib/khash.h lib/object.h lib/state.h lib/vm.h
 
diff --git a/lib/ext/boot.c b/lib/ext/boot.c
index c6a9a70e..d9c46c10 100644
--- a/lib/ext/boot.c
+++ b/lib/ext/boot.c
@@ -164,104 +164,114 @@ static const char boot_rom[][80] = {
 " ,@body))))))) (define-macro letrec-syntax (lambda (form env) (let ((formal (car",
 " (cdr form))) (body (cdr (cdr form)))) `(let () ,@(map (lambda (x) `(,(the 'defi",
 "ne-syntax) ,(car x) ,(cadr x))) formal) ,@body)))) (define-macro let-syntax (lam",
-"bda (form env) `(,(the 'letrec-syntax) ,@(cdr form)))) (define (mangle name) (wh",
-"en (null? name) (error \"library name should be a list of at least one symbols\" n",
-"ame)) (define (->string n) (cond ((symbol? n) (let ((str (symbol->string n))) (s",
-"tring-for-each (lambda (c) (when (or (char=? c #\\.) (char=? c #\\:)) (error \"elem",
-"ents of library name may not contain '.' or ':'\" n))) str) str)) ((and (number? ",
-"n) (exact? n) (<= 0 n)) (number->string n)) (else (error \"symbol or non-negative",
-" integer is required\" n)))) (define (join strs delim) (let loop ((res (car strs)",
-") (strs (cdr strs))) (if (null? strs) res (loop (string-append res delim (car st",
-"rs)) (cdr strs))))) (if (symbol? name) name (string->symbol (join (map ->string ",
-"name) \".\")))) (define current-library (make-parameter '(picrin base) mangle)) (d",
-"efine *libraries* (make-dictionary)) (define (find-library name) (dictionary-has",
-"? *libraries* (mangle name))) (define (make-library name) (let ((name (mangle na",
-"me))) (let ((env (make-environment (string->symbol (string-append (symbol->strin",
-"g name) \":\")))) (exports (make-dictionary))) (set-identifier! 'define-library 'd",
-"efine-library env) (set-identifier! 'import 'import env) (set-identifier! 'expor",
-"t 'export env) (set-identifier! 'cond-expand 'cond-expand env) (dictionary-set! ",
-"*libraries* name `(,env unquote exports))))) (define (library-environment name) ",
-"(car (dictionary-ref *libraries* (mangle name)))) (define (library-exports name)",
-" (cdr (dictionary-ref *libraries* (mangle name)))) (define (library-import name ",
-"sym alias) (let ((uid (dictionary-ref (library-exports name) sym))) (let ((env (",
-"library-environment (current-library)))) (set-identifier! alias uid env)))) (def",
-"ine (library-export sym alias) (let ((env (library-environment (current-library)",
-")) (exports (library-exports (current-library)))) (dictionary-set! exports alias",
-" (find-identifier sym env)))) (define-macro define-library (lambda (form _) (let",
-" ((name (cadr form)) (body (cddr form))) (or (find-library name) (make-library n",
-"ame)) (parameterize ((current-library name)) (for-each (lambda (expr) (eval expr",
-" name)) body))))) (define-macro cond-expand (lambda (form _) (letrec ((test (lam",
-"bda (form) (or (eq? form 'else) (and (symbol? form) (memq form (features))) (and",
-" (pair? form) (case (car form) ((library) (find-library (cadr form))) ((not) (no",
-"t (test (cadr form)))) ((and) (let loop ((form (cdr form))) (or (null? form) (an",
-"d (test (car form)) (loop (cdr form)))))) ((or) (let loop ((form (cdr form))) (a",
-"nd (pair? form) (or (test (car form)) (loop (cdr form)))))) (else #f))))))) (let",
-" loop ((clauses (cdr form))) (if (null? clauses) #undefined (if (test (caar clau",
-"ses)) `(,the-begin ,@(cdar clauses)) (loop (cdr clauses)))))))) (define-macro im",
-"port (lambda (form _) (let ((caddr (lambda (x) (car (cdr (cdr x))))) (prefix (la",
-"mbda (prefix symbol) (string->symbol (string-append (symbol->string prefix) (sym",
-"bol->string symbol))))) (getlib (lambda (name) (if (find-library name) name (err",
-"or \"library not found\" name))))) (letrec ((extract (lambda (spec) (case (car spe",
-"c) ((only rename prefix except) (extract (cadr spec))) (else (getlib spec))))) (",
-"collect (lambda (spec) (case (car spec) ((only) (let ((alist (collect (cadr spec",
-")))) (map (lambda (var) (assq var alist)) (cddr spec)))) ((rename) (let ((alist ",
-"(collect (cadr spec))) (renames (map (lambda (x) `(,(car x) unquote (cadr x))) (",
-"cddr spec)))) (map (lambda (s) (or (assq (car s) renames) s)) alist))) ((prefix)",
-" (let ((alist (collect (cadr spec)))) (map (lambda (s) (cons (prefix (caddr spec",
-") (car s)) (cdr s))) alist))) ((except) (let ((alist (collect (cadr spec)))) (le",
-"t loop ((alist alist)) (if (null? alist) '() (if (memq (caar alist) (cddr spec))",
-" (loop (cdr alist)) (cons (car alist) (loop (cdr alist)))))))) (else (dictionary",
-"-map (lambda (x) (cons x x)) (library-exports (getlib spec)))))))) (letrec ((imp",
-"ort (lambda (spec) (let ((lib (extract spec)) (alist (collect spec))) (for-each ",
-"(lambda (slot) (library-import lib (cdr slot) (car slot))) alist))))) (for-each ",
-"import (cdr form))))))) (define-macro export (lambda (form _) (letrec ((collect ",
-"(lambda (spec) (cond ((symbol? spec) `(,spec unquote spec)) ((and (list? spec) (",
-"= (length spec) 3) (eq? (car spec) 'rename)) `(,(list-ref spec 1) unquote (list-",
-"ref spec 2))) (else (error \"malformed export\"))))) (export (lambda (spec) (let (",
-"(slot (collect spec))) (library-export (car slot) (cdr slot)))))) (for-each expo",
-"rt (cdr form))))) (let () (make-library '(picrin base)) (set-car! (dictionary-re",
-"f *libraries* (mangle '(picrin base))) default-environment) (let ((export-keywor",
-"ds (lambda (keywords) (let ((env (library-environment '(picrin base))) (exports ",
-"(library-exports '(picrin base)))) (for-each (lambda (keyword) (dictionary-set! ",
-"exports keyword keyword)) keywords))))) (export-keywords '(define lambda quote s",
-"et! if begin define-macro let let* letrec letrec* let-values let*-values define-",
-"values quasiquote unquote unquote-splicing and or cond case else => do when unle",
-"ss parameterize define-syntax syntax-quote syntax-unquote syntax-quasiquote synt",
-"ax-unquote-splicing let-syntax letrec-syntax syntax-error)) (export-keywords '(f",
-"eatures eq? eqv? equal? not boolean? boolean=? pair? cons car cdr null? set-car!",
-" set-cdr! caar cadr cdar cddr list? make-list list length append reverse list-ta",
-"il list-ref list-set! list-copy map for-each memq memv member assq assv assoc cu",
-"rrent-input-port current-output-port current-error-port port? input-port? output",
-"-port? port-open? close-port eof-object? eof-object read-u8 peek-u8 read-bytevec",
-"tor! write-u8 write-bytevector flush-output-port open-input-bytevector open-outp",
-"ut-bytevector get-output-bytevector number? exact? inexact? inexact exact = < > ",
-"<= >= + - * / number->string string->number procedure? apply symbol? symbol=? sy",
-"mbol->string string->symbol make-identifier identifier? identifier=? identifier-",
-"base identifier-environment vector? vector make-vector vector-length vector-ref ",
-"vector-set! vector-copy! vector-copy vector-append vector-fill! vector-map vecto",
-"r-for-each list->vector vector->list string->vector vector->string bytevector? b",
-"ytevector make-bytevector bytevector-length bytevector-u8-ref bytevector-u8-set!",
-" bytevector-copy! bytevector-copy bytevector-append bytevector->list list->bytev",
-"ector call-with-current-continuation call/cc values call-with-values char? char-",
-">integer integer->char char=? char<? char>? char<=? char>=? current-exception-ha",
-"ndlers with-exception-handler raise raise-continuable error error-object? error-",
-"object-message error-object-irritants error-object-type string? string make-stri",
-"ng string-length string-ref string-set! string-copy string-copy! string-fill! st",
-"ring-append string-map string-for-each list->string string->list string=? string",
-"<? string>? string<=? string>=? make-parameter with-dynamic-environment read mak",
-"e-dictionary dictionary? dictionary dictionary-has? dictionary-ref dictionary-se",
-"t! dictionary-delete! dictionary-size dictionary-map dictionary-for-each diction",
-"ary->alist alist->dictionary dictionary->plist plist->dictionary make-record rec",
-"ord? record-type record-datum default-environment make-environment find-identifi",
-"er set-identifier! eval make-ephemeron-table write write-simple write-shared dis",
-"play)) (export-keywords '(find-library make-library current-library))) (set! eva",
-"l (let ((e eval)) (lambda (expr . lib) (let ((lib (if (null? lib) (current-libra",
-"ry) (car lib)))) (e expr (library-environment lib)))))) (make-library '(picrin u",
-"ser)) (current-library '(picrin user))) ",
+"bda (form env) `(,(the 'letrec-syntax) ,@(cdr form)))) ",
+
 };
 
+#if PIC_USE_LIBRARY
+static const char boot_library_rom[][80] = {
+"(define (mangle name) (when (null? name) (error \"library name should be a list o",
+"f at least one symbols\" name)) (define (->string n) (cond ((symbol? n) (let ((st",
+"r (symbol->string n))) (string-for-each (lambda (c) (when (or (char=? c #\\.) (ch",
+"ar=? c #\\:)) (error \"elements of library name may not contain '.' or ':'\" n))) s",
+"tr) str)) ((and (number? n) (exact? n) (<= 0 n)) (number->string n)) (else (erro",
+"r \"symbol or non-negative integer is required\" n)))) (define (join strs delim) (",
+"let loop ((res (car strs)) (strs (cdr strs))) (if (null? strs) res (loop (string",
+"-append res delim (car strs)) (cdr strs))))) (if (symbol? name) name (string->sy",
+"mbol (join (map ->string name) \".\")))) (define current-library (make-parameter '",
+"(picrin base) mangle)) (define *libraries* (make-dictionary)) (define (find-libr",
+"ary name) (dictionary-has? *libraries* (mangle name))) (define (make-library nam",
+"e) (let ((name (mangle name))) (let ((env (make-environment (string->symbol (str",
+"ing-append (symbol->string name) \":\")))) (exports (make-dictionary))) (set-ident",
+"ifier! 'define-library 'define-library env) (set-identifier! 'import 'import env",
+") (set-identifier! 'export 'export env) (set-identifier! 'cond-expand 'cond-expa",
+"nd env) (dictionary-set! *libraries* name `(,env unquote exports))))) (define (l",
+"ibrary-environment name) (car (dictionary-ref *libraries* (mangle name)))) (defi",
+"ne (library-exports name) (cdr (dictionary-ref *libraries* (mangle name)))) (def",
+"ine (library-import name sym alias) (let ((uid (dictionary-ref (library-exports ",
+"name) sym))) (let ((env (library-environment (current-library)))) (set-identifie",
+"r! alias uid env)))) (define (library-export sym alias) (let ((env (library-envi",
+"ronment (current-library))) (exports (library-exports (current-library)))) (dict",
+"ionary-set! exports alias (find-identifier sym env)))) (define-macro define-libr",
+"ary (lambda (form _) (let ((name (cadr form)) (body (cddr form))) (or (find-libr",
+"ary name) (make-library name)) (parameterize ((current-library name)) (for-each ",
+"(lambda (expr) (eval expr name)) body))))) (define-macro cond-expand (lambda (fo",
+"rm _) (letrec ((test (lambda (form) (or (eq? form 'else) (and (symbol? form) (me",
+"mq form (features))) (and (pair? form) (case (car form) ((library) (find-library",
+" (cadr form))) ((not) (not (test (cadr form)))) ((and) (let loop ((form (cdr for",
+"m))) (or (null? form) (and (test (car form)) (loop (cdr form)))))) ((or) (let lo",
+"op ((form (cdr form))) (and (pair? form) (or (test (car form)) (loop (cdr form))",
+")))) (else #f))))))) (let loop ((clauses (cdr form))) (if (null? clauses) #undef",
+"ined (if (test (caar clauses)) `(,the-begin ,@(cdar clauses)) (loop (cdr clauses",
+")))))))) (define-macro import (lambda (form _) (let ((caddr (lambda (x) (car (cd",
+"r (cdr x))))) (prefix (lambda (prefix symbol) (string->symbol (string-append (sy",
+"mbol->string prefix) (symbol->string symbol))))) (getlib (lambda (name) (if (fin",
+"d-library name) name (error \"library not found\" name))))) (letrec ((extract (lam",
+"bda (spec) (case (car spec) ((only rename prefix except) (extract (cadr spec))) ",
+"(else (getlib spec))))) (collect (lambda (spec) (case (car spec) ((only) (let ((",
+"alist (collect (cadr spec)))) (map (lambda (var) (assq var alist)) (cddr spec)))",
+") ((rename) (let ((alist (collect (cadr spec))) (renames (map (lambda (x) `(,(ca",
+"r x) unquote (cadr x))) (cddr spec)))) (map (lambda (s) (or (assq (car s) rename",
+"s) s)) alist))) ((prefix) (let ((alist (collect (cadr spec)))) (map (lambda (s) ",
+"(cons (prefix (caddr spec) (car s)) (cdr s))) alist))) ((except) (let ((alist (c",
+"ollect (cadr spec)))) (let loop ((alist alist)) (if (null? alist) '() (if (memq ",
+"(caar alist) (cddr spec)) (loop (cdr alist)) (cons (car alist) (loop (cdr alist)",
+"))))))) (else (dictionary-map (lambda (x) (cons x x)) (library-exports (getlib s",
+"pec)))))))) (letrec ((import (lambda (spec) (let ((lib (extract spec)) (alist (c",
+"ollect spec))) (for-each (lambda (slot) (library-import lib (cdr slot) (car slot",
+"))) alist))))) (for-each import (cdr form))))))) (define-macro export (lambda (f",
+"orm _) (letrec ((collect (lambda (spec) (cond ((symbol? spec) `(,spec unquote sp",
+"ec)) ((and (list? spec) (= (length spec) 3) (eq? (car spec) 'rename)) `(,(list-r",
+"ef spec 1) unquote (list-ref spec 2))) (else (error \"malformed export\"))))) (exp",
+"ort (lambda (spec) (let ((slot (collect spec))) (library-export (car slot) (cdr ",
+"slot)))))) (for-each export (cdr form))))) (let () (make-library '(picrin base))",
+" (set-car! (dictionary-ref *libraries* (mangle '(picrin base))) default-environm",
+"ent) (let ((export-keywords (lambda (keywords) (let ((env (library-environment '",
+"(picrin base))) (exports (library-exports '(picrin base)))) (for-each (lambda (k",
+"eyword) (dictionary-set! exports keyword keyword)) keywords))))) (export-keyword",
+"s '(define lambda quote set! if begin define-macro let let* letrec letrec* let-v",
+"alues let*-values define-values quasiquote unquote unquote-splicing and or cond ",
+"case else => do when unless parameterize define-syntax syntax-quote syntax-unquo",
+"te syntax-quasiquote syntax-unquote-splicing let-syntax letrec-syntax syntax-err",
+"or)) (export-keywords '(features eq? eqv? equal? not boolean? boolean=? pair? co",
+"ns car cdr null? set-car! set-cdr! caar cadr cdar cddr list? make-list list leng",
+"th append reverse list-tail list-ref list-set! list-copy map for-each memq memv ",
+"member assq assv assoc current-input-port current-output-port current-error-port",
+" port? input-port? output-port? port-open? close-port eof-object? eof-object rea",
+"d-u8 peek-u8 read-bytevector! write-u8 write-bytevector flush-output-port open-i",
+"nput-bytevector open-output-bytevector get-output-bytevector number? exact? inex",
+"act? inexact exact = < > <= >= + - * / number->string string->number procedure? ",
+"apply symbol? symbol=? symbol->string string->symbol make-identifier identifier?",
+" identifier=? identifier-base identifier-environment vector? vector make-vector ",
+"vector-length vector-ref vector-set! vector-copy! vector-copy vector-append vect",
+"or-fill! vector-map vector-for-each list->vector vector->list string->vector vec",
+"tor->string bytevector? bytevector make-bytevector bytevector-length bytevector-",
+"u8-ref bytevector-u8-set! bytevector-copy! bytevector-copy bytevector-append byt",
+"evector->list list->bytevector call-with-current-continuation call/cc values cal",
+"l-with-values char? char->integer integer->char char=? char<? char>? char<=? cha",
+"r>=? current-exception-handlers with-exception-handler raise raise-continuable e",
+"rror error-object? error-object-message error-object-irritants error-object-type",
+" string? string make-string string-length string-ref string-set! string-copy str",
+"ing-copy! string-fill! string-append string-map string-for-each list->string str",
+"ing->list string=? string<? string>? string<=? string>=? make-parameter with-dyn",
+"amic-environment read make-dictionary dictionary? dictionary dictionary-has? dic",
+"tionary-ref dictionary-set! dictionary-delete! dictionary-size dictionary-map di",
+"ctionary-for-each dictionary->alist alist->dictionary dictionary->plist plist->d",
+"ictionary make-record record? record-type record-datum default-environment make-",
+"environment find-identifier set-identifier! eval make-ephemeron-table write writ",
+"e-simple write-shared display)) (export-keywords '(find-library make-library cur",
+"rent-library))) (set! eval (let ((e eval)) (lambda (expr . lib) (let ((lib (if (",
+"null? lib) (current-library) (car lib)))) (e expr (library-environment lib))))))",
+" (make-library '(picrin user)) (current-library '(picrin user))) ",
+
+};
+#endif
+
 void
 pic_boot(pic_state *pic)
 {
   pic_load_cstr(pic, &boot_rom[0][0]);
+#if PIC_USE_LIBRARY
+  pic_load_cstr(pic, &boot_library_rom[0][0]);
+#endif
 }
diff --git a/lib/ext/lib.c b/lib/ext/lib.c
index 3f646c26..824c5772 100644
--- a/lib/ext/lib.c
+++ b/lib/ext/lib.c
@@ -5,6 +5,8 @@
 #include "picrin.h"
 #include "picrin/extra.h"
 
+#if PIC_USE_LIBRARY
+
 void
 pic_deflibrary(pic_state *pic, const char *lib)
 {
@@ -38,3 +40,5 @@ pic_export(pic_state *pic, int n, ...)
   va_end(ap);
   pic_leave(pic, ai);
 }
+
+#endif
diff --git a/lib/include/picconf.h b/lib/include/picconf.h
index 9faed22f..33e2d804 100644
--- a/lib/include/picconf.h
+++ b/lib/include/picconf.h
@@ -10,6 +10,7 @@
 
 /** enable specific features */
 /* #define PIC_USE_WRITE 1 */
+/* #define PIC_USE_LIBRARY 1 */
 
 /** essential external functions */
 /* #define PIC_JMPBUF jmp_buf */
diff --git a/lib/include/picrin/extra.h b/lib/include/picrin/extra.h
index 3e38c451..e0a15212 100644
--- a/lib/include/picrin/extra.h
+++ b/lib/include/picrin/extra.h
@@ -29,9 +29,11 @@ pic_value pic_fopen(pic_state *, FILE *, const char *mode);
  * library
  */
 
+#if PIC_USE_LIBRARY
 void pic_deflibrary(pic_state *, const char *lib);
 void pic_in_library(pic_state *, const char *lib);
 void pic_export(pic_state *, int n, ...);
+#endif
 
 
 /* for debug */
diff --git a/lib/include/picrin/setup.h b/lib/include/picrin/setup.h
index 5e0ff189..c3c8f826 100644
--- a/lib/include/picrin/setup.h
+++ b/lib/include/picrin/setup.h
@@ -16,6 +16,10 @@
 # define PIC_USE_WRITE 1
 #endif
 
+#ifndef PIC_USE_LIBRARY
+# define PIC_USE_LIBRARY 1
+#endif
+
 #ifndef PIC_JMPBUF
 # include <setjmp.h>
 # define PIC_JMPBUF jmp_buf
diff --git a/src/tiny-main.c b/src/tiny-main.c
new file mode 100644
index 00000000..253af54e
--- /dev/null
+++ b/src/tiny-main.c
@@ -0,0 +1,39 @@
+/**
+ * See Copyright Notice in picrin.h
+ */
+
+#include "picrin.h"
+#include "picrin/extra.h"
+
+int
+main()
+{
+  pic_state *pic;
+  pic_value e, form;
+  int status;
+
+  pic = pic_open(pic_default_allocf, NULL);
+
+  pic_try {
+    while (1) {
+      size_t ai = pic_enter(pic);
+      pic_printf(pic, "> ");
+      form = pic_read(pic, pic_stdin(pic));
+      if (pic_eof_p(pic, form)) {
+        break;
+      }
+      pic_printf(pic, "~s\n", pic_funcall(pic, "eval", 1, form));
+      pic_leave(pic, ai);
+    }
+
+    status = 0;
+  }
+  pic_catch(e) {
+    pic_print_error(pic, pic_stderr(pic), e);
+    status = 1;
+  }
+
+  pic_close(pic);
+
+  return status;
+}
diff --git a/tools/mkboot.scm b/tools/mkboot.scm
index dc4a6a9a..37a6e9aa 100644
--- a/tools/mkboot.scm
+++ b/tools/mkboot.scm
@@ -1,52 +1,63 @@
 (import (scheme base)
         (scheme read)
-        (scheme write))
+        (scheme write)
+        (scheme file))
 
-(define (with-output-to-string thunk)
-  (let ((port (open-output-string)))
-    (parameterize ((current-output-port port))
-      (thunk)
-      (let ((s (get-output-string port)))
-        (close-port port)
-        s))))
+(define (generate-rom filename)
 
-(define exprs
-  (let loop ((acc '()))
-    (let ((e (read)))
-      (if (eof-object? e)
+  (define (with-output-to-string thunk)
+    (let ((port (open-output-string)))
+      (parameterize ((current-output-port port))
+        (thunk)
+        (let ((s (get-output-string port)))
+          (close-port port)
+          s))))
+
+  (define exprs
+    (with-input-from-file filename
+      (lambda ()
+        (let loop ((acc '()))
+          (let ((e (read)))
+            (if (eof-object? e)
+                (reverse acc)
+                (loop (cons e acc))))))))
+
+  (define text
+    (with-output-to-string
+      (lambda ()
+        (for-each
+         (lambda (e)
+           (write e)
+           (write-string " "))
+         exprs))))
+
+  (define (escape-string s)
+    (with-output-to-string
+      (lambda ()
+        (string-for-each
+         (lambda (c)
+           (case c
+             ((#\\) (write-string "\\\\"))
+             ((#\") (write-string "\\\""))
+             ((#\newline) (write-string "\\n"))
+             (else (write-char c))))
+         s))))
+
+  (define (group-string i s)
+    (let loop ((t s) (n (string-length s)) (acc '()))
+      (if (= n 0)
           (reverse acc)
-          (loop (cons e acc))))))
+          (if (< n i)
+              (loop "" 0 (cons t acc))
+              (loop (string-copy t i) (- n i) (cons (string-copy t 0 i) acc))))))
 
-(define text
-  (with-output-to-string
-    (lambda ()
-      (for-each
-       (lambda (e)
-         (write e)
-         (write-string " "))
-       exprs))))
+  (define lines (map escape-string (group-string 80 text)))
 
-(define (escape-string s)
-  (with-output-to-string
-    (lambda ()
-      (string-for-each
-       (lambda (c)
-         (case c
-           ((#\\) (write-string "\\\\"))
-           ((#\") (write-string "\\\""))
-           ((#\newline) (write-string "\\n"))
-           (else (write-char c))))
-       s))))
+  (let loop ((lines lines) (acc ""))
+       (if (null? lines)
+           acc
+           (loop (cdr lines) (string-append acc "\"" (car lines) "\",\n")))))
 
-(define (group-string i s)
-  (let loop ((t s) (n (string-length s)) (acc '()))
-    (if (= n 0)
-        (reverse acc)
-        (if (< n i)
-            (loop "" 0 (cons t acc))
-            (loop (string-copy t i) (- n i) (cons (string-copy t 0 i) acc))))))
-
-(define lines (map escape-string (group-string 80 text)))
 
 (for-each
  (lambda (s) (display s) (newline))
@@ -54,15 +65,21 @@
    "#include \"picrin/extra.h\""
    ""
    "static const char boot_rom[][80] = {"
-   ,@(let loop ((lines lines) (acc '()))
-       (if (null? lines)
-           (reverse acc)
-           (loop (cdr lines) (cons (string-append "\"" (car lines) "\",") acc))))
+   ,(generate-rom "piclib/boot.scm")
    "};"
    ""
+   "#if PIC_USE_LIBRARY"
+   "static const char boot_library_rom[][80] = {"
+   ,(generate-rom "piclib/library.scm")
+   "};"
+   "#endif"
+   ""
    "void"
    "pic_boot(pic_state *pic)"
    "{"
    "  pic_load_cstr(pic, &boot_rom[0][0]);"
+   "#if PIC_USE_LIBRARY"
+   "  pic_load_cstr(pic, &boot_library_rom[0][0]);"
+   "#endif"
    "}"))