diff --git a/src/exe/cimbar_recv2/recv2.cpp b/src/exe/cimbar_recv2/recv2.cpp
index 7c4cef52..34b0a3ca 100644
--- a/src/exe/cimbar_recv2/recv2.cpp
+++ b/src/exe/cimbar_recv2/recv2.cpp
@@ -150,17 +150,28 @@ int main(int argc, char** argv)
 			// attempt save
 			uint32_t fileId = res;
 
-			unsigned size = cimbard_get_filesize(fileId);
-			std::string filename = fmt::format("0.{}", size);
-			std::cerr << "Saving file " << filename << " of size " << size << std::endl;
+			int size = cimbard_get_filesize(fileId);
+
+			std::string filename;
+			filename.resize(255, '\0');
+			int fnsize = cimbard_get_filename(fileId, filename.data(), filename.size());
+			if (fnsize > 0)
+				filename.resize(fnsize);
+			else // fallback
+				filename = fmt::format("0.{}", size);
+			std::cerr << "Saving file " << filename << " of (compressed) size " << size << std::endl;
+
+			std::string file_path = fmt::format("{}/{}", outpath, filename);
+			std::ofstream outs(file_path, std::ios::binary);
 
 			std::vector<unsigned char> data;
-			data.resize(size);
-			int res = cimbard_finish_copy(fileId, data.data(), size);
-			if (res != 0)
-				std::cerr << "failed fountain_finish_copy " << res << std::endl;
+			data.resize(cimbard_get_decompress_bufsize());
 
-			decompress_on_store<std::ofstream>(outpath, true)(filename, data);
+			int res = 1;
+			while ((res = cimbard_decompress_read(fileId, data.data(), data.size())) > 0)
+				outs.write(reinterpret_cast<const char*>(data.data()), res);
+			if (res < 0)
+				std::cerr << "failed cimbard_decompress_read " << res << std::endl;
 		}
 	}
 
diff --git a/src/lib/cimbar_js/CMakeLists.txt b/src/lib/cimbar_js/CMakeLists.txt
index ffce5a5c..dc3f2679 100644
--- a/src/lib/cimbar_js/CMakeLists.txt
+++ b/src/lib/cimbar_js/CMakeLists.txt
@@ -14,8 +14,6 @@ set(SOURCES
 
 	cimbar_recv_js.h
 	cimbar_recv_js.cpp
-	cimbar_zstd_js.h
-	cimbar_zstd_js.cpp
 )
 endif()
 
@@ -66,16 +64,14 @@ set(LINK_WASM_EXPORTED_FUNCTIONS
 	${LINK_WASM_EXPORTED_FUNCTIONS}
 
 	, "_cimbard_get_report"
+	, "_cimbard_get_bufsize"
 	, "_cimbard_scan_extract_decode"
 	, "_cimbard_fountain_decode"
-	, "_cimbard_get_bufsize"
 	, "_cimbard_get_filesize"
 	, "_cimbard_get_filename"
-	, "_cimbard_finish_copy"
+	, "_cimbard_get_decompress_bufsize"
+	, "_cimbard_decompress_read"
 	, "_cimbard_configure_decode"
-	, "_cimbarz_init_decompress"
-	, "_cimbarz_get_bufsize"
-	, "_cimbarz_decompress_read"
 )
 endif()
 
diff --git a/src/lib/cimbar_js/cimbar_recv_js.cpp b/src/lib/cimbar_js/cimbar_recv_js.cpp
index 570e612c..0564d416 100644
--- a/src/lib/cimbar_js/cimbar_recv_js.cpp
+++ b/src/lib/cimbar_js/cimbar_recv_js.cpp
@@ -19,10 +19,16 @@
 
 
 namespace {
-
+	// for decode
 	std::shared_ptr<fountain_decoder_sink> _sink;
-	std::string _reporting;
 
+	// for decompress
+	// we support only one decompress at a time!
+	uint32_t _decId = 0;
+	std::vector<uchar> _reassembled;
+	std::unique_ptr<cimbar::zstd_decompressor<std::stringstream>> _dec;
+
+	std::string _reporting;
 	cv::Mat _debugFrame;
 
 	TimeAccumulator _tScanExtract;
@@ -31,6 +37,48 @@ namespace {
 	// settings
 	int _modeVal = 68;
 
+	// set up stateful decompressor
+	// for api simplicity, this is coupled to recover_contents()
+	// ... but we *could* split them up
+	int init_decompress(uint32_t id)
+	{
+		if (id != _decId)
+			return -11;
+		if (_dec)
+			_dec.reset();
+		_dec = std::make_unique<cimbar::zstd_decompressor<std::stringstream>>();
+		if (!_dec)
+			return -12;
+		_dec->init_decompress(reinterpret_cast<char*>(_reassembled.data()), _reassembled.size());
+		return 0;
+	}
+
+	// recovers file contents into _reassembled, and sets _decId = id if so.
+	// if the contents cannot be recovered, amounts to a no-op with error
+	int recover_contents(uint32_t id)
+	{
+		if (id != _decId)
+		{
+			if (!_sink)
+				return -1;
+			if (_sink->is_done(id))
+				return -2; // it's gone man
+
+			_reassembled.resize(cimbard_get_filesize(id));
+			if (!_sink->recover(id, _reassembled.data(), _reassembled.size()))
+				return -3;
+			_decId = id;
+
+			int res = init_decompress(id);
+			if (res < 0)
+				return res;
+		}
+		if (_reassembled.empty())
+			return -5;
+
+		return 0;
+	}
+
 	unsigned fountain_chunks_per_frame()
 	{
 		return cimbar::Config::fountain_chunks_per_frame(
@@ -166,14 +214,24 @@ int64_t cimbard_fountain_decode(const unsigned char* buffer, unsigned size)
 	return res;
 }
 
-int cimbard_get_filesize(uint32_t id)
+// mostly for internal use, but also helpful for debugging
+unsigned cimbard_get_filesize(uint32_t id)
 {
 	FountainMetadata md(id);
 	return md.file_size();
 }
 
-int cimbard_get_filename(const uchar* finbuffer, unsigned size, char* filename, unsigned fnsize)
+// do recover() if does not exist (fail with appropriate neg values), if it does use the bytes.
+// stateful against a map (same as cimbard_decompress_read()
+int cimbard_get_filename(uint32_t id, char* filename, unsigned fnsize)
 {
+	int	res = recover_contents(id);
+	if (res < 0)
+		return res;
+
+	const uchar* finbuffer = _reassembled.data();
+	unsigned size = _reassembled.size();
+
 	std::string fn = cimbar::zstd_header_check::get_filename(finbuffer, size);
 	if (!fn.empty())
 		fn = File::basename(fn);
@@ -186,15 +244,29 @@ int cimbard_get_filename(const uchar* finbuffer, unsigned size, char* filename,
 	return fn.size();
 }
 
-// if fountain_decode returned a >0 value, call this to retrieve the reassembled file
-// bouth fountain_*() calls should be from the same js webworker/thread
-int cimbard_finish_copy(uint32_t id, uchar* buffer, unsigned size)
+int cimbard_decompress_read(uint32_t id, unsigned char* buffer, unsigned size)
 {
-	if (!_sink)
-		return -1;
-	if (!_sink->recover(id, buffer, size))
-		return -2;
-	return 0;
+	int	res = recover_contents(id);
+	if (res < 0)
+		return res;
+
+	if (!_dec)
+		return -13;
+	if (!_dec->good())
+		return -14;
+
+	_dec->str(std::string());
+	_dec->write_once();
+	std::string temp = _dec->str();
+	if (size > temp.size())
+		size = temp.size();
+	std::copy(temp.data(), temp.data()+size, buffer);
+	return size;
+}
+
+int cimbard_get_decompress_bufsize()
+{
+	return ZSTD_DStreamOutSize();
 }
 
 int cimbard_configure_decode(int mode_val)
@@ -215,4 +287,12 @@ int cimbard_configure_decode(int mode_val)
 	return 0;
 }
 
+// testing
+unsigned char* cimbard_get_reassembled_file_buff()
+{
+	if (_reassembled.empty())
+		return nullptr;
+	return _reassembled.data();
+}
+
 }
diff --git a/src/lib/cimbar_js/cimbar_recv_js.h b/src/lib/cimbar_js/cimbar_recv_js.h
index eb0e1111..608efe8c 100644
--- a/src/lib/cimbar_js/cimbar_recv_js.h
+++ b/src/lib/cimbar_js/cimbar_recv_js.h
@@ -20,20 +20,24 @@ int cimbard_scan_extract_decode(const unsigned char* imgdata, unsigned imgw, uns
 // persists state, the return value (if >0) corresponds to a uint32_t id
 int64_t cimbard_fountain_decode(const unsigned char* buffer, unsigned size);
 
-// get filesize from id
-int cimbard_get_filesize(uint32_t id);
-
-// if fountain_decode returned a >0 value, call this to retrieve the reassembled file
-// wherever a uint32_t id is passed, it should be on the same js thread
-// ... or at least in the same js shared memory...
-// as the fountain_decode() call
-int cimbard_finish_copy(uint32_t id, unsigned char* finbuffer, unsigned size);
-
-// get filename from reassembled file
-int cimbard_get_filename(const unsigned char* finbuffer, unsigned size, char* filename, unsigned fnsize);
+// get compressed filesize from id
+// you probably don't need to use this.
+unsigned cimbard_get_filesize(uint32_t id);
+
+// if fountain_decode returned a >0 value,
+//  get filename and (partial) contents from reassembled file
+// wherever a uint32_t id is passed, it should be in the
+//  same js shared memory as the fountain_decode() call
+// cimbard_decompress_read() will return 0 when all file contents have been read
+int cimbard_get_filename(uint32_t id, char* filename, unsigned fnsize);
+int cimbard_get_decompress_bufsize();
+int cimbard_decompress_read(uint32_t id, unsigned char* buffer, unsigned size);
 
 int cimbard_configure_decode(int mode_val);
 
+// testing usage only!
+unsigned char* cimbard_get_reassembled_file_buff();
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/lib/cimbar_js/cimbar_zstd_js.cpp b/src/lib/cimbar_js/cimbar_zstd_js.cpp
deleted file mode 100644
index 6135c480..00000000
--- a/src/lib/cimbar_js/cimbar_zstd_js.cpp
+++ /dev/null
@@ -1,49 +0,0 @@
-/* This code is subject to the terms of the Mozilla Public License, v.2.0. http://mozilla.org/MPL/2.0/. */
-#include "cimbar_zstd_js.h"
-
-#include "compression/zstd_decompressor.h"
-
-#include <memory>
-#include <sstream>
-
-namespace {
-	// maybe a map eventually
-	std::unique_ptr<cimbar::zstd_decompressor<std::stringstream>> _dec;
-
-}
-
-// zstd_decompressor constructor, reads skippable frame at start? (needs to for ofstream case)
-// if we make _dec a map, this'll also take the uin32_t id we got from the decoder sink, probably
-int cimbarz_init_decompress(unsigned char* buffer, unsigned size)
-{
-	if (_dec)
-		_dec.reset();
-
-	_dec = std::make_unique<cimbar::zstd_decompressor<std::stringstream>>();
-	if (!_dec)
-		return -1;
-	_dec->init_decompress(reinterpret_cast<char*>(buffer), size);
-	return 0;
-}
-
-int cimbarz_get_bufsize()
-{
-	return ZSTD_DStreamOutSize();
-}
-
-// "decompress_chunk()/write()"
-int cimbarz_decompress_read(unsigned char* buffer, unsigned size)
-{
-	if (!_dec)
-		return -1;
-	if (!_dec->good())
-		return -2;
-
-	_dec->str(std::string());
-	_dec->write_once();
-	std::string temp = _dec->str();
-	if (size > temp.size())
-		size = temp.size();
-	std::copy(temp.data(), temp.data()+size, buffer);
-	return size;
-}
diff --git a/src/lib/cimbar_js/cimbar_zstd_js.h b/src/lib/cimbar_js/cimbar_zstd_js.h
deleted file mode 100644
index 371f038f..00000000
--- a/src/lib/cimbar_js/cimbar_zstd_js.h
+++ /dev/null
@@ -1,20 +0,0 @@
-/* This code is subject to the terms of the Mozilla Public License, v.2.0. http://mozilla.org/MPL/2.0/. */
-#ifndef CIMBAR_ZSTD_JS_API_H
-#define CIMBAR_ZSTD_JS_API_H
-
-#include <stdint.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-int cimbarz_init_decompress(unsigned char* buffer, unsigned size);
-int cimbarz_get_filename(char* buffer, unsigned size);
-int cimbarz_get_bufsize();
-int cimbarz_decompress_read(unsigned char* buffer, unsigned size);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif // CIMBAR_ZSTD_JS_API_H
diff --git a/src/lib/cimbar_js/test/cimbar_jsTest.cpp b/src/lib/cimbar_js/test/cimbar_jsTest.cpp
index ff91c6d7..06bd5eff 100644
--- a/src/lib/cimbar_js/test/cimbar_jsTest.cpp
+++ b/src/lib/cimbar_js/test/cimbar_jsTest.cpp
@@ -5,7 +5,6 @@
 #include "cimb_translator/Config.h"
 #include "cimbar_js/cimbar_js.h"
 #include "cimbar_js/cimbar_recv_js.h"
-#include "cimbar_js/cimbar_zstd_js.h"
 #include "serialize/format.h"
 
 #include <iostream>
@@ -55,27 +54,17 @@ TEST_CASE( "cimbar_jsTest/testRoundtrip", "[unit]" )
 	{
 		uint32_t fileId = res;
 
-		unsigned size = cimbard_get_filesize(fileId);
-		assertEquals( 5282, size );
-
-		std::vector<unsigned char> data;
-		data.resize(size);
-		int res = cimbard_finish_copy(fileId, data.data(), size);
-		assertEquals( 0, res );
-
 		std::string actualFilename;
 		actualFilename.resize(255);
-		int fnsz = cimbard_get_filename(data.data(), size, actualFilename.data(), actualFilename.size());
+		int fnsz = cimbard_get_filename(fileId, actualFilename.data(), actualFilename.size());
 		assertEquals( 21, fnsz );
 		actualFilename.resize(fnsz);
 		assertEquals( "foobar-c语言版.txt", actualFilename );
 
-		assertEquals(0, cimbarz_init_decompress(data.data(), data.size()));
-
 		std::vector<unsigned char> zstdbuff;
-		zstdbuff.resize(cimbarz_get_bufsize());
+		zstdbuff.resize(cimbard_get_decompress_bufsize());
 
-		int outsize = cimbarz_decompress_read(zstdbuff.data(), zstdbuff.size());
+		int outsize = cimbard_decompress_read(fileId, zstdbuff.data(), zstdbuff.size());
 		assertEquals(contents.size(), outsize);
 		std::string_view finalOutput{reinterpret_cast<char*>(zstdbuff.data()), contents.size()};
 
diff --git a/src/lib/cimbar_js/test/cimbar_recv_jsTest.cpp b/src/lib/cimbar_js/test/cimbar_recv_jsTest.cpp
index 5bca3f01..d0fc1ae1 100644
--- a/src/lib/cimbar_js/test/cimbar_recv_jsTest.cpp
+++ b/src/lib/cimbar_js/test/cimbar_recv_jsTest.cpp
@@ -83,9 +83,14 @@ TEST_CASE( "cimbar_recv_jsTest/testWirehairReassemble", "[unit]" )
 	assertTrue(dec > 0);
 	assertEquals(SIZE, cimbard_get_filesize(dec));
 
-	std::string reassembled(SIZE, '\0');
-	assertEquals(0, cimbard_finish_copy(dec, reinterpret_cast<unsigned char*>(reassembled.data()), SIZE));
-
+	// first call to cimbard_get_filename or cimbard_decompress_read() reassembles file
+	std::string actualFilename;
+	actualFilename.resize(255);
+	assertEquals(0, cimbard_get_filename(dec, actualFilename.data(), actualFilename.size())); // no filename though
+
+	unsigned char* data = cimbard_get_reassembled_file_buff();
+	assertFalse( data == nullptr );
+	std::string_view reassembled(reinterpret_cast<const char*>(data), SIZE);
 	assertEquals(contents, reassembled);
 }
 
@@ -109,18 +114,26 @@ TEST_CASE( "cimbar_recv_jsTest/testFullDecode", "[unit]" )
 	{
 		uint32_t fileId = res;
 
-		unsigned size = cimbard_get_filesize(fileId);
-		assertEquals( 7347, size );
+		assertEquals( 7347, cimbard_get_filesize(fileId) );
+
+		unsigned size = cimbard_get_decompress_bufsize();
+		assertEquals( 131072, size ); // defined by zstd. sanity check
 
 		std::vector<unsigned char> data;
 		data.resize(size);
-		int res = cimbard_finish_copy(fileId, data.data(), size);
-		assertEquals( 0, res );
 
-		cimbar::zstd_decompressor<std::stringstream> dss;
-		assertTrue( dss.write(reinterpret_cast<char*>(data.data()), data.size()) );
+		std::stringstream ss;
+		int res = 1;
+		while (res > 0)
+		{
+			res = cimbard_decompress_read(fileId, data.data(), data.size());
+			if (res == 0)
+				break;
+			assertTrue( res > 0 );
+			ss.write(reinterpret_cast<const char*>(data.data()), res);
+		}
 
-		assertEquals( 7538, dss.str().size() );
+		assertEquals( 7538, ss.str().size() ); // decompressed
 	}
 
 }
diff --git a/web/main.js b/web/main.js
index c76a5fa6..859d79b9 100644
--- a/web/main.js
+++ b/web/main.js
@@ -61,6 +61,7 @@ var Main = function () {
       var height = window.innerHeight - 10;
       Main.scaleCanvas(canvas, width, height);
       Main.alignInvisibleClick(canvas);
+      Main.checkNavButtonOverlap();
     },
 
     toggleFullscreen: function () {
@@ -210,10 +211,6 @@ var Main = function () {
         _renderTime += elapsed;
         Main.setHTML("status", elapsed + " : " + frameCount + " : " + Math.ceil(_renderTime / frameCount));
       }
-      if (!(_counter & 15)) {
-        Main.resize();
-        Main.checkNavButtonOverlap();
-      }
     },
 
     setActive: function (active) {
@@ -366,3 +363,7 @@ window.addEventListener("drop", function (e) {
   Main.dragDrop(e);
   document.body.style["opacity"] = 1.0;
 }, false);
+
+window.addEventListener('resize', () => {
+  Main.resize();
+});
\ No newline at end of file
diff --git a/web/recv.js b/web/recv.js
index 05cd7832..62045676 100644
--- a/web/recv.js
+++ b/web/recv.js
@@ -55,31 +55,22 @@ var Sink = function () {
     reassemble_file: function (id) {
       const size = Module._cimbard_get_filesize(id);
       //alert("we did it!?! " + size);
-      const dataPtr = Module._malloc(size);
-      const buff = new Uint8Array(Module.HEAPU8.buffer, dataPtr, size);
       try {
-        var res = Module._cimbard_finish_copy(id, buff.byteOffset, buff.length);
-        if (res < 0) {
+        var name = id + "." + size;
+        const fnsize = Module._cimbard_get_filename(id, _errBuff, _errBuffSize);
+        if (fnsize < 0) {
           alert("reassemble_file failed :(" + res);
           console.log("we biffed it. :( " + res);
           Recv.set_HTML("errorbox", "reassemble_file failed :( " + res);
         }
-        else {
-          var name = id + "." + size;
-          const fnsize = Module._cimbard_get_filename(buff.byteOffset, buff.length, _errBuff, _errBuffSize);
-          if (fnsize > 0) {
-            const temparr = new Uint8Array(Module.HEAPU8.buffer, _errBuff, fnsize);
-            name = new TextDecoder("utf-8").decode(temparr);
-          }
-          //Recv.download_bytes(buff, size + ".zst"); // size -> name, eventually
-          Zstd.decompress(name, buff);
+        else if (fnsize > 0) {
+          const temparr = new Uint8Array(Module.HEAPU8.buffer, _errBuff, fnsize);
+          name = new TextDecoder("utf-8").decode(temparr);
         }
+        Zstd.decompress(name, id);
       } catch (error) {
         console.log("failed finish copy or download?? " + error);
       }
-      // this needs to happen after decompress() completes
-      // currently decompress is sync, so it's fine. But...
-      Module._free(dataPtr);
     }
   };
 }();
diff --git a/web/test/test_base.js b/web/test/test_base.js
index 00b176f9..893988c3 100644
--- a/web/test/test_base.js
+++ b/web/test/test_base.js
@@ -1,19 +1,13 @@
 QUnit.module("base");
 QUnit.config.reorder = false;
+QUnit.config.testTimeout = 10000;
 
-var Zstd = function () {
-
-  // public interface
-  return {
-
-    calls: [],
-
-    decompress: function (name, data) {
-      Zstd.calls.push({ decompress: [name, data.length] });
-    }
-  };
-}();
+let _zstdCalls = [];
 
+Zstd.download_blob = function (name, blob) {
+  console.log("in fake download blob for " + name);
+  _zstdCalls.push({ download_blob: [name, blob.size] });
+};
 
 function wait_for(assert, block) {
   var done = assert.async();
@@ -56,7 +50,7 @@ QUnit.testStart(async function (details) {
 });
 
 QUnit.testDone(function (details) {
-
+  _zstdCalls = [];
 });
 
 QUnit.test("stable decode", async function (assert) {
@@ -90,7 +84,7 @@ QUnit.test("stable decode", async function (assert) {
     return document.querySelector(query);
   });
   assert.equal(pro2.style.width, "92.3077%");
-  assert.deepEqual(Zstd.calls, []);
+  assert.deepEqual(_zstdCalls, []);
 
   pro2.remove();
 
@@ -103,7 +97,11 @@ QUnit.test("stable decode", async function (assert) {
   });
   assert.equal(pro3.style.width, "100%");
 
-  assert.deepEqual(Zstd.calls, [
-    { decompress: ["576454656.23586", 23586] }
+  // might be something better to wait on, but for now this is fine.
+  const numCalls = await wait_for(assert, () => {
+    return _zstdCalls.length > 0;
+  });
+  assert.deepEqual(_zstdCalls, [
+    { download_blob: ["576454656.23586", 23947] }
   ]);
 });
diff --git a/web/test_recv.html b/web/test_recv.html
index 63d5ef3e..1e93fe49 100644
--- a/web/test_recv.html
+++ b/web/test_recv.html
@@ -23,6 +23,7 @@
 
 
   <script src="recv.js"></script>
+  <script src="zstd.js"></script>
 
   <script type="text/javascript">
     Recv.init_ww(1);
diff --git a/web/zstd.js b/web/zstd.js
index ae809b7c..dc07460d 100644
--- a/web/zstd.js
+++ b/web/zstd.js
@@ -1,22 +1,7 @@
 var Zstd = function () {
 
-  var _activeBuff = undefined;
   var _decompBuff = undefined;
 
-  function allocBuff(data) {
-    freeBuff();
-    const numBytes = data.length * data.BYTES_PER_ELEMENT;
-    const dataPtr = Module._malloc(numBytes);
-    _activeBuff = new Uint8Array(Module.HEAPU8.buffer, dataPtr, numBytes);
-    _activeBuff.set(data);
-  }
-
-  function freeBuff() {
-    if (_activeBuff)
-      Module._free(_activeBuff.byteOffset);
-    _activeBuff = undefined;
-  }
-
   function _downloadHelper(name, bloburl) {
     var aaa = document.createElement('a');
     aaa.href = bloburl;
@@ -27,22 +12,17 @@ var Zstd = function () {
     aaa.remove();
   }
 
-  function getDecompressReader(inbuff) {
+  function getDecompressReader(id) {
     // allocate buffer once. We'll reuse it,
     // and slice() to copy to the local (non-wasm) heap
-    const bufferSize = Module._cimbarz_get_bufsize(); // chunk size
+    const bufferSize = Module._cimbard_get_decompress_bufsize(); // chunk size
     if (_decompBuff === undefined)
       _decompBuff = Module._malloc(bufferSize);
 
     const readstream = new ReadableStream({
-      start(controller) {
-        const res = Module._cimbarz_init_decompress(inbuff.byteOffset, inbuff.length);
-        if (res < 0) {
-          console.log("init decompress failed, res " + res);
-        }
-      },
+      start(controller) { },
       pull(controller) {
-        const bytesRead = Module._cimbarz_decompress_read(_decompBuff, bufferSize);
+        const bytesRead = Module._cimbard_decompress_read(id, _decompBuff, bufferSize);
         console.log("reader got " + bytesRead);
         if (bytesRead <= 0) {
           // No more data, close the stream
@@ -87,6 +67,7 @@ var Zstd = function () {
     // Create Response object from the stream, get blob
     const response = new Response(readstream);
     const blob = await response.blob();
+    console.log("download is ready for " + filename + ", size " + blob.size);
     Zstd.download_blob(filename, blob);
   }
 
@@ -109,10 +90,8 @@ var Zstd = function () {
       }, 1000);
     },
 
-    decompress: function (name, data) {
-      allocBuff(data);
-
-      const reader = getDecompressReader(_activeBuff);
+    decompress: function (name, id) {
+      const reader = getDecompressReader(id);
 
       saveToFile(reader, name);
     }