diff --git a/bbnurse b/bbnurse
index 3da8cff..07078a9 100755
--- a/bbnurse
+++ b/bbnurse
@@ -1,7 +1,7 @@
 #!/bin/bash
 # -*- coding: utf-8 mode: sh -*- vim:sw=4:sts=4:et:ai:si:sta:fenc=utf-8
-#source /etc/nulib.sh || exit 1
-source "$(dirname -- "$0")/vendor/nulib/php/load.sh" || exit 1
+source /etc/nulib.sh || exit 1
+#source "$(dirname -- "$0")/vendor/nulib/php/load.sh" || exit 1
 
 function copy_nurse() {
     :
@@ -20,9 +20,16 @@ function copy_mature() {
         setx src=abspath "$src"
         [ "${src#$MYDIR/src/}" != "$src" ] || die "la source doit être dans nur-sery/src/"
         src="${src#$MYDIR/src/}"
-        path="${src%/*}"
-        filename="${src##*/}"
+        if [[ "$src" == */* ]]; then
+            path="${src%/*}"
+            filename="${src##*/}"
+        else
+            path=
+            filename="$src"
+        fi
         class="${filename%.php}"
+        srcdir="$MYDIR/src"
+        src="$srcdir/$src"
     elif [ -d "$src" ]; then
         # répertoire de package
         setx src=abspath "$src"
@@ -48,14 +55,13 @@ function copy_mature() {
         destpackage='nulib'
     fi
 
-    local dest="${1:-.}"; shift
-    setx dest=abspath "$dest"
-    if [[ "$dest" == */nulib ]]; then
+    setx Dest=abspath "$Dest"
+    if [[ "$Dest" == */nulib ]]; then
         libname=nulib
-        libdir="$dest"
-    elif [[ "$dest" == */nulib/* ]]; then
+        libdir="$Dest"
+    elif [[ "$Dest" == */nulib/* ]]; then
         libname=nulib
-        libdir="${dest%%/nulib/*}/nulib"
+        libdir="${Dest%%/nulib/*}/nulib"
     else
         die "seul la maturation vers nulib est supporté"
     fi
@@ -75,7 +81,12 @@ function copy_mature() {
 
         if [ -n "$class" ]; then
             # Maturation d'un seul fichier
-            die "TODO"
+            etitle "Maturation de $srcpackage vers $destpackage"
+            srcname="${src#$srcdir/}"
+            dest="$destdir/$srcname"
+            estep "$srcname"
+            mkdirof "$dest"
+            sed "s|${nurserypackage//\\/\\\\}|${nulibpackage//\\/\\\\}|g" <"$src" >"$dest"
         else
             # Maturation de toute un package
             etitle "Maturation de $srcpackage vers $destpackage"
@@ -84,7 +95,7 @@ function copy_mature() {
             for src in "${srcs[@]}"; do
                 srcname="${src#$srcdir/}"
                 dest="$destdir/$srcname"
-                estep "${src#$srcdir/}"
+                estep "$srcname"
                 mkdirof "$dest"
                 sed "s|${nurserypackage//\\/\\\\}|${nulibpackage//\\/\\\\}|g" <"$src" >"$dest"
             done
@@ -113,14 +124,17 @@ function update_mature() {
     :
 }
 
-action=update
+action=copy
 evolution=mature
+Dest=
 args=(
     "Gérer la maturation d'une classe ou d'un package"
     "
+-cm SRC [-d DEST]
 -cn SRC
--cm SRC [DEST]
--u[n|m] package|Class [DEST]
+-u[n|m] package|Class [-d DEST]
+
+IMPORTANT: pour l'instant, seule la copie à maturation (-cm) est implémentée
 
 Il y a deux types d'évolutions possibles:
 * mettre en nurserie (-n)
@@ -142,6 +156,7 @@ Pour chaque type d'évolution, il y a deux actions possibles:
     la version mature à maturation
   L'argument est un 'package' ou un 'sous\\package' (dont le nom commence par
   une minuscule) ou une 'Classe' (dont le nom commence par une majuscule)"
+    -d:,--dest Dest= "Spécifier la destination"
     -c,--copy action=copy "Copier de/vers un projet nulib-*"
     -u,--update action=update "Mettre à jour un projet. C'est l'option par défaut"
     -i,-n,--nurse evolution=nurse "Mettre en nurserie"
@@ -149,4 +164,5 @@ Pour chaque type d'évolution, il y a deux actions possibles:
 )
 parse_args "$@"; set -- "${args[@]}"
 
+[ -n "$Dest" ] || Dest=.
 "${action}_${evolution}" "$@"
diff --git a/nur_src/b/io/TmpfileWriter.php b/nur_src/b/io/TmpfileWriter.php
index ff02e6b..d24588d 100644
--- a/nur_src/b/io/TmpfileWriter.php
+++ b/nur_src/b/io/TmpfileWriter.php
@@ -1,6 +1,7 @@
 <?php
 namespace nur\b\io;
 
+use nur\sery\file\base\FileReader;
 use nur\v\http;
 
 /**
diff --git a/nur_src/ref/ref_type.php b/nur_src/ref/ref_type.php
index 4beb6c0..4465c50 100644
--- a/nur_src/ref/ref_type.php
+++ b/nur_src/ref/ref_type.php
@@ -3,6 +3,7 @@ namespace nur\ref;
 
 use nur\data\types\Metadata;
 use nur\md;
+use nur\sery\os\file\file;
 
 /**
  * Class ref_type: référence des types utilisables dans les schémas
@@ -104,7 +105,7 @@ class ref_type {
   /** comme {@link CONTENT} mais nullable */
   const NCONTENT = "?".self::CONTENT;
 
-  /** comme {@link FILE} mais nullable */
+  /** comme {@link \nur\sery\FILE} mais nullable */
   const NFILE = "?".self::FILE;
 
   /** comme {@link DATETIME} mais nullable */
diff --git a/src/cv.php b/src/cv.php
index 5e6812e..7bc1779 100644
--- a/src/cv.php
+++ b/src/cv.php
@@ -79,6 +79,15 @@ class cv {
 
   #############################################################################
 
+  /** échanger les deux valeurs */
+  static final function swap(&$a, &$b): void {
+    $tmp = $a;
+    $a = $b;
+    $b = $tmp;
+  }
+
+  #############################################################################
+
   /** mettre à jour $dest avec $value si $cond($value) est vrai */
   static final function set_if(&$dest, $value, callable $cond) {
     if ($cond($value)) $dest = $value;
diff --git a/src/os/file.php b/src/file.php
similarity index 86%
rename from src/os/file.php
rename to src/file.php
index 2c8d047..b296cfa 100644
--- a/src/os/file.php
+++ b/src/file.php
@@ -1,12 +1,12 @@
 <?php
-namespace nur\sery\os;
+namespace nur\sery;
 
-use nur\sery\os\file\FileReader;
-use nur\sery\os\file\FileWriter;
-use nur\sery\os\file\MemoryStream;
-use nur\sery\os\file\SharedFile;
-use nur\sery\os\file\TempStream;
-use nur\sery\os\file\TmpfileWriter;
+use nur\sery\file\base\FileReader;
+use nur\sery\file\base\FileWriter;
+use nur\sery\file\base\MemoryStream;
+use nur\sery\file\base\SharedFile;
+use nur\sery\file\base\TempStream;
+use nur\sery\file\base\TmpfileWriter;
 
 /**
  * Class file: outils pour gérer les fichiers
diff --git a/src/os/file/IReader.php b/src/file/IReader.php
similarity index 98%
rename from src/os/file/IReader.php
rename to src/file/IReader.php
index 9a6da2f..5d38fc5 100644
--- a/src/os/file/IReader.php
+++ b/src/file/IReader.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file;
 
 use nur\sery\os\EOFException;
 use nur\sery\os\IOException;
diff --git a/src/os/file/IWriter.php b/src/file/IWriter.php
similarity index 97%
rename from src/os/file/IWriter.php
rename to src/file/IWriter.php
index 38a6559..7cf2d13 100644
--- a/src/os/file/IWriter.php
+++ b/src/file/IWriter.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file;
 
 use nur\sery\os\IOException;
 
diff --git a/src/os/file/_IFile.php b/src/file/_IFile.php
similarity index 98%
rename from src/os/file/_IFile.php
rename to src/file/_IFile.php
index bc83896..1967049 100644
--- a/src/os/file/_IFile.php
+++ b/src/file/_IFile.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file;
 
 use Iterator;
 use nur\sery\os\IOException;
diff --git a/src/os/file/FileReader.php b/src/file/base/FileReader.php
similarity index 95%
rename from src/os/file/FileReader.php
rename to src/file/base/FileReader.php
index 6b2377d..717d8cf 100644
--- a/src/os/file/FileReader.php
+++ b/src/file/base/FileReader.php
@@ -1,7 +1,5 @@
 <?php
-namespace nur\sery\os\file;
-
-use nur\sery\os\IOException;
+namespace nur\sery\file\base;
 
 /**
  * Class FileReader: un fichier accédé en lecture
diff --git a/src/os/file/FileWriter.php b/src/file/base/FileWriter.php
similarity index 93%
rename from src/os/file/FileWriter.php
rename to src/file/base/FileWriter.php
index 5260ce3..b4c78f8 100644
--- a/src/os/file/FileWriter.php
+++ b/src/file/base/FileWriter.php
@@ -1,9 +1,8 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
 use nur\sery\os\IOException;
 use nur\sery\os\sh;
-use nur\sery\web\http;
 
 /**
  * Class FileWriter: un fichier accédé en lecture/écriture
diff --git a/src/os/file/MemoryStream.php b/src/file/base/MemoryStream.php
similarity index 89%
rename from src/os/file/MemoryStream.php
rename to src/file/base/MemoryStream.php
index 25a1d9b..46f2c94 100644
--- a/src/os/file/MemoryStream.php
+++ b/src/file/base/MemoryStream.php
@@ -1,7 +1,5 @@
 <?php
-namespace nur\sery\os\file;
-
-use nur\sery\os\IOException;
+namespace nur\sery\file\base;
 
 /**
  * Class MemoryStream: un flux qui peut être lu ou écrit, et qui reste
diff --git a/src/os/file/SharedFile.php b/src/file/base/SharedFile.php
similarity index 92%
rename from src/os/file/SharedFile.php
rename to src/file/base/SharedFile.php
index 3d93b99..738a251 100644
--- a/src/os/file/SharedFile.php
+++ b/src/file/base/SharedFile.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
 use nur\sery\ValueException;
 
diff --git a/src/os/file/Stream.php b/src/file/base/Stream.php
similarity index 99%
rename from src/os/file/Stream.php
rename to src/file/base/Stream.php
index 4ed0296..97486d6 100644
--- a/src/os/file/Stream.php
+++ b/src/file/base/Stream.php
@@ -1,8 +1,10 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
+use nur\sery\file\csv\csv_flavours;
+use nur\sery\file\IReader;
+use nur\sery\file\IWriter;
 use nur\sery\NoMoreDataException;
-use nur\sery\os\csv\csv_flavours;
 use nur\sery\os\EOFException;
 use nur\sery\os\IOException;
 use nur\sery\php\iter\AbstractIterator;
diff --git a/src/os/file/TStreamFilter.php b/src/file/base/TStreamFilter.php
similarity index 80%
rename from src/os/file/TStreamFilter.php
rename to src/file/base/TStreamFilter.php
index 36a9c45..4fe3def 100644
--- a/src/os/file/TStreamFilter.php
+++ b/src/file/base/TStreamFilter.php
@@ -1,18 +1,19 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
-use nur\A;
-use nur\b\io\IOException;
+use nur\sery\file\_IFile;
+use nur\sery\os\IOException;
 
 trait TStreamFilter {
   private $filters = null;
 
   function appendFilter(string $filterName, ?int $readWrite=null, $params=null): void {
-    A::append($this->filters, [$filterName, $readWrite, $params]);
+    $this->filters[] = [$filterName, $readWrite, $params];
   }
 
   function prependFilter(string $filterName, ?int $readWrite=null, $params=null): void {
-    A::prepend($this->filters, [$filterName, $readWrite, $params]);
+    if ($this->filters === null) $this->filters = [];
+    array_unshift($this->filters, [$filterName, $readWrite, $params]);
   }
 
   function setEncodingFilter(string $from, string $to): void {
diff --git a/src/os/file/TempStream.php b/src/file/base/TempStream.php
similarity index 96%
rename from src/os/file/TempStream.php
rename to src/file/base/TempStream.php
index 60ef9c6..bb1f1dd 100644
--- a/src/os/file/TempStream.php
+++ b/src/file/base/TempStream.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
 /**
  * Class TempStream: un flux qui peut être lu ou écrit, et qui reste en mémoire,
diff --git a/src/os/file/TmpfileWriter.php b/src/file/base/TmpfileWriter.php
similarity index 98%
rename from src/os/file/TmpfileWriter.php
rename to src/file/base/TmpfileWriter.php
index d1a21a0..3c78990 100644
--- a/src/os/file/TmpfileWriter.php
+++ b/src/file/base/TmpfileWriter.php
@@ -1,9 +1,8 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
 use nur\sery\os\IOException;
 use nur\sery\os\path;
-use nur\sery\web\http;
 
 /**
  * Class TmpfileWriter: un fichier temporaire accédé en lecture/écriture
diff --git a/src/os/file/_File.php b/src/file/base/_File.php
similarity index 97%
rename from src/os/file/_File.php
rename to src/file/base/_File.php
index 51de904..69be147 100644
--- a/src/os/file/_File.php
+++ b/src/file/base/_File.php
@@ -1,5 +1,5 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
 use nur\sery\os\IOException;
 use nur\sery\web\http;
diff --git a/src/os/csv/csv_flavours.php b/src/file/csv/csv_flavours.php
similarity index 90%
rename from src/os/csv/csv_flavours.php
rename to src/file/csv/csv_flavours.php
index c240249..8a00603 100644
--- a/src/os/csv/csv_flavours.php
+++ b/src/file/csv/csv_flavours.php
@@ -1,8 +1,8 @@
 <?php
-namespace nur\sery\os\csv;
+namespace nur\sery\file\csv;
 
-use nur\A;
-use nur\ref\ref_csv;
+use nur\sery\cl;
+use nur\sery\ref\os\csv\ref_csv;
 
 class csv_flavours {
   const MAP = [
@@ -41,6 +41,6 @@ class csv_flavours {
   }
 
   static final function get_encoding(string $flavour): ?string {
-    return A::get(self::ENCODINGS, $flavour);
+    return cl::get(self::ENCODINGS, $flavour);
   }
 }
diff --git a/src/output/std/StdOutput.php b/src/output/std/StdOutput.php
index f04c406..ba541a4 100644
--- a/src/output/std/StdOutput.php
+++ b/src/output/std/StdOutput.php
@@ -3,7 +3,7 @@ namespace nur\sery\output\std;
 
 use Exception;
 use nur\sery\cl;
-use nur\sery\os\file\Stream;
+use nur\sery\file\base\Stream;
 use nur\sery\php\content\content;
 use nur\sery\php\content\IContent;
 use nur\sery\php\content\IPrintable;
diff --git a/src/str.php b/src/str.php
index 0176966..a289c68 100644
--- a/src/str.php
+++ b/src/str.php
@@ -1,8 +1,6 @@
 <?php
 namespace nur\sery;
 
-use nur\base;
-
 /**
  * Class str: gestion des chaines de caractère "simples"
  */
diff --git a/tests/os/file/FileReaderTest.php b/tests/file/base/FileReaderTest.php
similarity index 81%
rename from tests/os/file/FileReaderTest.php
rename to tests/file/base/FileReaderTest.php
index 37d48dd..d27673e 100644
--- a/tests/os/file/FileReaderTest.php
+++ b/tests/file/base/FileReaderTest.php
@@ -1,13 +1,14 @@
 <?php
-namespace nur\sery\os\file;
+namespace nur\sery\file\base;
 
+use nur\sery\file\base\FileReader;
 use PHPUnit\Framework\TestCase;
 
 class FileReaderTest extends TestCase {
   function testIgnoreBom() {
     # la lecture avec et sans BOM doit être identique
     ## sans BOM
-    $reader = new FileReader(__DIR__.'/impl/sans_bom.txt');
+    $reader = new FileReader(__DIR__ . '/impl/sans_bom.txt');
     self::assertSame("0123456789", $reader->fread(10));
     self::assertSame(10, $reader->ftell());
     $reader->seek(30);
@@ -20,7 +21,7 @@ class FileReaderTest extends TestCase {
     self::assertSame("0123456789\n", $reader->getContents());
     $reader->close();
     ## avec BOM
-    $reader = new FileReader(__DIR__.'/impl/avec_bom.txt');
+    $reader = new FileReader(__DIR__ . '/impl/avec_bom.txt');
     self::assertSame("0123456789", $reader->fread(10));
     self::assertSame(10, $reader->ftell());
     $reader->seek(30);
@@ -35,25 +36,25 @@ class FileReaderTest extends TestCase {
   }
 
   function testCsvAutoParams() {
-    $reader = new FileReader(__DIR__.'/impl/msexcel.csv');
+    $reader = new FileReader(__DIR__ . '/impl/msexcel.csv');
     self::assertSame(["nom", "prenom", "age"], $reader->fgetcsv());
     self::assertSame(["clain", "jephte", "50"], $reader->fgetcsv());
     self::assertNull($reader->fgetcsv());
     $reader->close();
 
-    $reader = new FileReader(__DIR__.'/impl/ooffice.csv');
+    $reader = new FileReader(__DIR__ . '/impl/ooffice.csv');
     self::assertSame(["nom", "prenom", "age"], $reader->fgetcsv());
     self::assertSame(["clain", "jephte", "50"], $reader->fgetcsv());
     self::assertNull($reader->fgetcsv());
     $reader->close();
 
-    $reader = new FileReader(__DIR__.'/impl/weird.tsv');
+    $reader = new FileReader(__DIR__ . '/impl/weird.tsv');
     self::assertSame(["nom", "prenom", "age"], $reader->fgetcsv());
     self::assertSame(["clain", "jephte", "50"], $reader->fgetcsv());
     self::assertNull($reader->fgetcsv());
     $reader->close();
 
-    $reader = new FileReader(__DIR__.'/impl/avec_bom.csv');
+    $reader = new FileReader(__DIR__ . '/impl/avec_bom.csv');
     self::assertSame(["nom", "prenom", "age"], $reader->fgetcsv());
     self::assertSame(["clain", "jephte", "50"], $reader->fgetcsv());
     self::assertNull($reader->fgetcsv());
diff --git a/tests/os/file/impl/avec_bom.csv b/tests/file/base/impl/avec_bom.csv
similarity index 100%
rename from tests/os/file/impl/avec_bom.csv
rename to tests/file/base/impl/avec_bom.csv
diff --git a/tests/os/file/impl/avec_bom.txt b/tests/file/base/impl/avec_bom.txt
similarity index 100%
rename from tests/os/file/impl/avec_bom.txt
rename to tests/file/base/impl/avec_bom.txt
diff --git a/tests/os/file/impl/msexcel.csv b/tests/file/base/impl/msexcel.csv
similarity index 100%
rename from tests/os/file/impl/msexcel.csv
rename to tests/file/base/impl/msexcel.csv
diff --git a/tests/os/file/impl/ooffice.csv b/tests/file/base/impl/ooffice.csv
similarity index 100%
rename from tests/os/file/impl/ooffice.csv
rename to tests/file/base/impl/ooffice.csv
diff --git a/tests/os/file/impl/sans_bom.txt b/tests/file/base/impl/sans_bom.txt
similarity index 100%
rename from tests/os/file/impl/sans_bom.txt
rename to tests/file/base/impl/sans_bom.txt
diff --git a/tests/os/file/impl/weird.tsv b/tests/file/base/impl/weird.tsv
similarity index 100%
rename from tests/os/file/impl/weird.tsv
rename to tests/file/base/impl/weird.tsv
diff --git a/tests/php/time/DateTest.php b/tests/php/time/DateTest.php
index d77676e..7f3458a 100644
--- a/tests/php/time/DateTest.php
+++ b/tests/php/time/DateTest.php
@@ -2,7 +2,7 @@
 namespace nur\sery\php\time;
 
 use DateTimeZone;
-use PHPUnit\Framework\TestCase;
+use nulib\tests\TestCase;
 
 class DateTest extends TestCase {
   protected static function dt(string $datetime): Date {
diff --git a/tests/php/time/DateTimeTest.php b/tests/php/time/DateTimeTest.php
index 7e004ca..00455f1 100644
--- a/tests/php/time/DateTimeTest.php
+++ b/tests/php/time/DateTimeTest.php
@@ -2,7 +2,7 @@
 namespace nur\sery\php\time;
 
 use DateTimeZone;
-use PHPUnit\Framework\TestCase;
+use nulib\tests\TestCase;
 
 class DateTimeTest extends TestCase {
   protected static function dt(string $datetime): DateTime {
diff --git a/tests/php/time/DelayTest.php b/tests/php/time/DelayTest.php
index f2fc5cf..55cb054 100644
--- a/tests/php/time/DelayTest.php
+++ b/tests/php/time/DelayTest.php
@@ -2,9 +2,7 @@
 namespace nur\sery\php\time;
 
 use DateTimeZone;
-use nur\sery\php\time\DateTime;
-use nur\sery\php\time\Delay;
-use nur\t\TestCase;
+use nulib\tests\TestCase;
 
 class DelayTest extends TestCase {
   protected static function dt(string $datetime): DateTime {