diff --git a/rebuild.cmd b/rebuild.cmd
index dc2fc94..25facc0 100644
--- a/rebuild.cmd
+++ b/rebuild.cmd
@@ -1,5 +1,7 @@
 @echo off
 
+set PHP=C:\bin\php54\php.exe
+
 echo Cleaning target directory...
 echo.
 rmdir /s /q wwwroot
@@ -9,6 +11,10 @@ copy static\* wwwroot
 
 echo Building pages...
 echo.
-C:\bin\php54\php.exe rebuild.php
+%PHP% rebuild.php 4 0
+%PHP% rebuild.php 4 1
+%PHP% rebuild.php 4 2
+%PHP% rebuild.php 4 3
+%PHP% rebuild.php 4 4
 
 pause
\ No newline at end of file
diff --git a/rebuild.php b/rebuild.php
index 009cfb1..65b0359 100644
--- a/rebuild.php
+++ b/rebuild.php
@@ -112,6 +112,17 @@ function text2html($sz) {
 	return nl2br($base);
 }
 
+function array_decimate($array, $total, $partno) {
+	$ct = 0;
+	$ret = [];
+	foreach($array as $k => $v) {
+		if (++$ct % $total == ($partno - 1)) {
+			$ret[$k] = $v;
+		}
+	}
+	return $ret;
+}
+
 /**
  * 
  */
@@ -149,7 +160,8 @@ class CProject {
 					$this->tags = array_map('trim', explode(',', $matches[1]));
 				}
 				
-				$this->shortdesc = array_shift(explode("\n", $this->longdesc));
+				$parts = explode("\n", $this->longdesc);
+				$this->shortdesc = array_shift($parts);
 				$this->shortdesc[0] = strtolower($this->shortdesc[0]); // cosmetic lowercase
 				continue;
 			}
@@ -162,6 +174,18 @@ class CProject {
 		}
 	}
 	
+	public function genHomeImage() {		
+		if (count($this->images)) {
+			
+			$this->homeimage = mkthumbnail(
+				$this->dir.$this->images[0], //BASEDIR.'wwwroot/srv/'.$this->projname.'_0.'.str_ext($this->images[0]),
+				null, // raw handle
+				INDEX_THUMB_W, INDEX_THUMB_H
+			);
+		}
+		
+	}
+	
 	public function write() {
 		
 		// Generate image thumbnails
@@ -173,14 +197,6 @@ class CProject {
 			mkthumbnail($outfile.'.'.str_ext($image), $outfile.'_thumb.jpg', PAGE_THUMB_W, PAGE_THUMB_H);
 		}
 		
-		if (count($this->images)) {
-			$this->homeimage = mkthumbnail(
-				BASEDIR.'wwwroot/srv/'.$this->projname.'_0.'.str_ext($this->images[0]),
-				null, // raw handle
-				INDEX_THUMB_W, INDEX_THUMB_H
-			);
-		}
-		
 		// Copy downloads to wwwroot
 		
 		foreach($this->downloads as $idx => $filename) {
@@ -276,8 +292,7 @@ function template($title, $content) {
 	return ob_get_clean();
 }
 
-function buildall() {
-	
+function listprojects() {
 	// List projects
 
 	$ls = scandir(BASEDIR.'data');
@@ -291,21 +306,40 @@ function buildall() {
 			$projects[$dirname] = $matches[1];
 		}
 	}
+	
+	return $projects;
+}
+
+function buildprojects($id, $projects) {
+	$count = 0;
+	
+	foreach($projects as $dirname => $projectname) {
+
+		echo sprintf("@%1d [%3d/%3d] ".$projectname."...\n", $id, ++$count, count($projects));
+
+		$pr = new CProject($dirname, $projectname);	
+		$pr->write();
+	}
+}
+
+function buildcommon() {
+	
+	echo "@0 [  0/  ?] Common files...\n";
+	
+	$projects = listprojects();
 
 	// Build all projects
 
 	$plist = array();
-	$count = 0;
 
 	$handles = array();
 	$handle_lookup = array();
 	
 	foreach($projects as $dirname => $projectname) {
 
-		echo sprintf("[%3d/%3d] ".$projectname."...", ++$count, count($projects));
-
-		$pr = new CProject($dirname, $projectname);	
-		$pr->write();
+		$pr = new CProject($dirname, $projectname);
+		$pr->genHomeImage(); // thumbnail
+		
 		$plist[] = $pr;
 
 		if (is_null($pr->homeimage)) {
@@ -314,9 +348,7 @@ function buildall() {
 			$handle_lookup[$projectname] = count($handles);
 			$handles[] = $pr->homeimage;
 		}
-		
-		echo " done\n";
-	}	
+	}
 
 	// Build homepage spritesheet
 	
@@ -364,9 +396,25 @@ function buildall() {
 
 	$index = template(SITE_TITLE, ob_get_clean());
 	file_put_contents(BASEDIR.'wwwroot/index.html', $index);
-
-	echo "All processes complete.\n";
-
+	
+	// Done
 }
 
-buildall();
+function main($args) {
+	$total = $args[0];
+	$pos   = $args[1];
+	
+	if ($pos == 0) {
+		buildcommon();
+	} else {
+		buildprojects($pos, array_decimate(listprojects(), $total, $pos));
+	}
+}
+
+// Entry point
+//
+
+ini_set('display_errors', 'On');
+error_reporting(E_ALL);
+
+main(array_slice($_SERVER['argv'], 1));