diff --git a/packages/hxtorch/package.py b/packages/hxtorch/package.py
index e8c3bbaec65c8d690a2501b114a39e88fab722ac..b3201623341980353a78d2442a48bf3b9c7a65f0 100644
--- a/packages/hxtorch/package.py
+++ b/packages/hxtorch/package.py
@@ -23,6 +23,7 @@ class Hxtorch(build_brainscales.BuildBrainscales):
 
     maintainers = ['emuller']
 
+    version('8.0-a4',         tag='hxtorch-8.0-a4')
     version('8.0-a3',         tag='hxtorch-8.0-a3')
     version('8.0-a2',         tag='hxtorch-8.0-a2')
     version('8.0-a1',         tag='hxtorch-8.0-a1')
@@ -33,6 +34,7 @@ class Hxtorch(build_brainscales.BuildBrainscales):
     deps_hxtorch_core = [
         # compiler for the BrainScaleS-2 embedded processor ("PPU"); needed for
         # building/linking, at runtime and for testing
+        ('oppulance@8.0-a4', { "when":'@8.0-a4', "type": ('build', 'link', 'run', 'test') } ),
         ('oppulance@8.0-a3', { "when":'@8.0-a3', "type": ('build', 'link', 'run', 'test') } ),
         ('oppulance@8.0-a2', { "when":'@8.0-a2', "type": ('build', 'link', 'run', 'test') } ),
         ('oppulance@8.0-a1', { "when":'@8.0-a1', "type": ('build', 'link', 'run', 'test') } ),
@@ -53,7 +55,8 @@ class Hxtorch(build_brainscales.BuildBrainscales):
         ('intel-tbb', { "type": ('build', 'link', 'run') } ), # ppu gdbserver
         ('libelf', { "type": ('build', 'link', 'run') } ),
         ('liblockfile', { "type": ('build', 'link', 'run') } ),
-        ('log4cxx@0.12.1:', { "type": ('build', 'link', 'run') } ),
+        ('log4cxx@0.12.1:1.0', { "when": "@:8.0-a3", "type": ('build', 'link', 'run') } ),
+        ('log4cxx@1.1: +events_at_exit', { "when": "@8.0-a4:", "type": ('build', 'link', 'run') } ),
         ('pkgconfig', { "type": ('build', 'link', 'run') } ),
         ('psmisc', { "type": ('run', 'test') } ),
         ('python@3.7.0:', { "type": ('build', 'link', 'run') } ), # BrainScaleS-2 only supports Python >= 3.7
diff --git a/packages/jaxsnn/package.py b/packages/jaxsnn/package.py
index 3fe246b417b13f5c949ab08bed70225697d3d486..c6b2021e5801a5d3f934b83e33d3b4f04e515ee7 100644
--- a/packages/jaxsnn/package.py
+++ b/packages/jaxsnn/package.py
@@ -25,6 +25,7 @@ class Jaxsnn(build_brainscales.BuildBrainscales):
 
     maintainers = ['emuller']
 
+    version('8.0-a4', tag='jaxsnn-8.0-a4')
     version('8.0-a3', tag='jaxsnn-8.0-a3')
     version('8.0-a2', tag='jaxsnn-8.0-a2')
     version('8.0-a1', tag='jaxsnn-8.0-a1')
diff --git a/packages/log4cxx/log4cxx-0.10.0-missing_includes.patch b/packages/log4cxx/log4cxx-0.10.0-missing_includes.patch
new file mode 100644
index 0000000000000000000000000000000000000000..6834648d09a826c18cf5755c406006c16accc36d
--- /dev/null
+++ b/packages/log4cxx/log4cxx-0.10.0-missing_includes.patch
@@ -0,0 +1,38 @@
+diff -Naur apache-log4cxx-0.10.0.orig/src/examples/cpp/console.cpp apache-log4cxx-0.10.0/src/examples/cpp/console.cpp
+--- apache-log4cxx-0.10.0.orig/src/examples/cpp/console.cpp	2008-04-01 00:34:52.000000000 +0200
++++ apache-log4cxx-0.10.0/src/examples/cpp/console.cpp	2008-05-06 05:40:52.000000000 +0200
+@@ -15,7 +15,10 @@
+  * limitations under the License.
+  */
+ 
+-#include <stdlib.h>
++#include <cstdio>
++#include <cstdlib>
++#include <cstring>
++#include <stdint.h>
+ #include <log4cxx/logger.h>
+ #include <log4cxx/consoleappender.h>
+ #include <log4cxx/simplelayout.h>
+diff -Naur apache-log4cxx-0.10.0.orig/src/main/cpp/inputstreamreader.cpp apache-log4cxx-0.10.0/src/main/cpp/inputstreamreader.cpp
+--- apache-log4cxx-0.10.0.orig/src/main/cpp/inputstreamreader.cpp	2008-04-01 00:34:09.000000000 +0200
++++ apache-log4cxx-0.10.0/src/main/cpp/inputstreamreader.cpp	2008-05-06 05:32:31.000000000 +0200
+@@ -21,6 +21,8 @@
+ #include <log4cxx/helpers/pool.h>
+ #include <log4cxx/helpers/bytebuffer.h>
+ 
++#include <cstring>
++
+ using namespace log4cxx;
+ using namespace log4cxx::helpers;
+ 
+diff -Naur apache-log4cxx-0.10.0.orig/src/main/cpp/socketoutputstream.cpp apache-log4cxx-0.10.0/src/main/cpp/socketoutputstream.cpp
+--- apache-log4cxx-0.10.0.orig/src/main/cpp/socketoutputstream.cpp	2008-04-01 00:34:09.000000000 +0200
++++ apache-log4cxx-0.10.0/src/main/cpp/socketoutputstream.cpp	2008-05-06 05:35:55.000000000 +0200
+@@ -20,6 +20,8 @@
+ #include <log4cxx/helpers/socket.h>
+ #include <log4cxx/helpers/bytebuffer.h>
+ 
++#include <cstring>
++
+ using namespace log4cxx;
+ using namespace log4cxx::helpers;
\ No newline at end of file
diff --git a/packages/log4cxx/log4cxx-0.10.0-narrowing-fixes-from-upstream.patch b/packages/log4cxx/log4cxx-0.10.0-narrowing-fixes-from-upstream.patch
new file mode 100644
index 0000000000000000000000000000000000000000..e583e7661d1d0adc0650dd3d96f5bf8d77aa6cbf
--- /dev/null
+++ b/packages/log4cxx/log4cxx-0.10.0-narrowing-fixes-from-upstream.patch
@@ -0,0 +1,117 @@
+diff --git a/src/main/cpp/locationinfo.cpp b/src/main/cpp/locationinfo.cpp
+index e76ea29..bd22a1d 100644
+--- a/src/main/cpp/locationinfo.cpp
++++ b/src/main/cpp/locationinfo.cpp
+@@ -149,18 +149,21 @@ void LocationInfo::write(ObjectOutputStream& os, Pool& p) const {
+          os.writeNull(p);
+     } else {
+         char prolog[] = {
+-         0x72, 0x00, 0x21, 0x6F, 0x72, 0x67, 0x2E, 
+-         0x61, 0x70, 0x61, 0x63, 0x68, 0x65, 0x2E, 0x6C, 
+-         0x6F, 0x67, 0x34, 0x6A, 0x2E, 0x73, 0x70, 0x69, 
+-         0x2E, 0x4C, 0x6F, 0x63, 0x61, 0x74, 0x69, 0x6F, 
+-         0x6E, 0x49, 0x6E, 0x66, 0x6F, 0xED, 0x99, 0xBB, 
+-         0xE1, 0x4A, 0x91, 0xA5, 0x7C, 0x02, 0x00, 0x01, 
+-         0x4C, 0x00, 0x08, 0x66, 0x75, 0x6C, 0x6C, 0x49, 
+-         0x6E, 0x66, 0x6F, 
+-            0x74, 0x00, 0x12, 0x4C, 0x6A, 
+-                0x61, 0x76, 0x61, 0x2F, 0x6C, 0x61, 0x6E, 0x67, 
+-                0x2F, 0x53, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x3B,
+-         0x78, 0x70 };
++         0x72,
++         0x00,
++         0x21, 0x6F, 0x72, 0x67, 0x2E, 0x61, 0x70, 0x61, 0x63, 0x68, 0x65, 0x2E,
++         0x6C, 0x6F, 0x67, 0x34, 0x6A, 0x2E, 0x73, 0x70, 0x69, 0x2E, 0x4C, 0x6F,
++         0x63, 0x61, 0x74, 0x69, 0x6F, 0x6E, 0x49, 0x6E, 0x66, 0x6F, static_cast<char>(0xED),
++         static_cast<char>(0x99), static_cast<char>(0xBB), static_cast<char>(0xE1),
++         0x4A, static_cast<char>(0x91), static_cast<char>(0xA5), 0x7C, 0x02,
++         0x00,
++         0x01, 0x4C,
++         0x00,
++         0x08, 0x66, 0x75, 0x6C, 0x6C, 0x49, 0x6E, 0x66, 0x6F, 0x74,
++         0x00,
++         0x12, 0x4C, 0x6A, 0x61, 0x76, 0x61, 0x2F, 0x6C, 0x61, 0x6E, 0x67, 0x2F,
++         0x53, 0x74, 0x72, 0x69, 0x6E, 0x67, 0x3B, 0x78, 0x70
++        };
+       os.writeProlog("org.apache.log4j.spi.LocationInfo", 2, prolog, sizeof(prolog), p);
+         char* line = p.itoa(lineNumber);
+         //
+diff --git a/src/main/cpp/loggingevent.cpp b/src/main/cpp/loggingevent.cpp
+index 1c0d4be..edbf40b 100644
+--- a/src/main/cpp/loggingevent.cpp
++++ b/src/main/cpp/loggingevent.cpp
+@@ -242,7 +242,7 @@ void LoggingEvent::writeProlog(ObjectOutputStream& os, Pool& p)  {
+         0x68, 0x65, 0x2E, 0x6C, 0x6F, 0x67, 0x34, 0x6A, 
+         0x2E, 0x73, 0x70, 0x69, 0x2E, 0x4C, 0x6F, 0x67, 
+         0x67, 0x69, 0x6E, 0x67, 0x45, 0x76, 0x65, 0x6E, 
+-        0x74, 0xF3, 0xF2, 0xB9, 0x23, 0x74, 0x0B, 0xB5, 
++        0x74, static_cast<char>(0xF3), static_cast<char>(0xF2), static_cast<char>(0xB9), 0x23, 0x74, 0x0B, static_cast<char>(0xB5), 
+         0x3F, 0x03, 0x00, 0x0A, 0x5A, 0x00, 0x15, 0x6D, 
+         0x64, 0x63, 0x43, 0x6F, 0x70, 0x79, 0x4C, 0x6F, 
+         0x6F, 0x6B, 0x75, 0x70, 0x52, 0x65, 0x71, 0x75, 
+diff --git a/src/main/cpp/objectoutputstream.cpp b/src/main/cpp/objectoutputstream.cpp
+index 7cd696b..5442420 100644
+--- a/src/main/cpp/objectoutputstream.cpp
++++ b/src/main/cpp/objectoutputstream.cpp
+@@ -36,7 +36,7 @@ ObjectOutputStream::ObjectOutputStream(OutputStreamPtr outputStream, Pool& p)
+        objectHandle(0x7E0000),
+        classDescriptions(new ClassDescriptionMap())
+ {
+-   char start[] = { 0xAC, 0xED, 0x00, 0x05 };
++   char start[] = { static_cast<char>(0xAC), static_cast<char>(0xED), 0x00, 0x05 };
+    ByteBuffer buf(start, sizeof(start));
+    os->write(buf, p);
+ }
+@@ -81,15 +81,15 @@ void ObjectOutputStream::writeObject(const MDC::Map& val, Pool& p) {
+     //
+     //  TC_OBJECT and the classDesc for java.util.Hashtable
+     //
+-    char prolog[] = {
+-        0x72, 0x00, 0x13, 0x6A, 0x61, 0x76, 0x61, 
+-        0x2E, 0x75, 0x74, 0x69, 0x6C, 0x2E, 0x48, 0x61, 
+-        0x73, 0x68, 0x74, 0x61, 0x62, 0x6C, 0x65, 0x13, 
+-        0xBB, 0x0F, 0x25, 0x21, 0x4A, 0xE4, 0xB8, 0x03, 
+-        0x00, 0x02, 0x46, 0x00, 0x0A, 0x6C, 0x6F, 0x61, 
+-        0x64, 0x46, 0x61, 0x63, 0x74, 0x6F, 0x72, 0x49, 
+-        0x00, 0x09, 0x74, 0x68, 0x72, 0x65, 0x73, 0x68, 
+-        0x6F, 0x6C, 0x64, 0x78, 0x70  };
++	char prolog[] = {
++		0x72, 0x00, 0x13, 0x6A, 0x61, 0x76, 0x61,
++		0x2E, 0x75, 0x74, 0x69, 0x6C, 0x2E, 0x48, 0x61,
++		0x73, 0x68, 0x74, 0x61, 0x62, 0x6C, 0x65, 0x13,
++		static_cast<char>(0xBB), 0x0F, 0x25, 0x21, 0x4A, static_cast<char>(0xE4), static_cast<char>(0xB8), 0x03,
++		0x00, 0x02, 0x46, 0x00, 0x0A, 0x6C, 0x6F, 0x61,
++		0x64, 0x46, 0x61, 0x63, 0x74, 0x6F, 0x72, 0x49,
++		0x00, 0x09, 0x74, 0x68, 0x72, 0x65, 0x73, 0x68,
++		0x6F, 0x6C, 0x64, 0x78, 0x70  };
+     writeProlog("java.util.Hashtable", 1, prolog, sizeof(prolog), p);
+     //
+     //   loadFactor = 0.75, threshold = 5, blockdata start, buckets.size = 7
+diff --git a/src/test/cpp/xml/domtestcase.cpp b/src/test/cpp/xml/domtestcase.cpp
+index a500628..29d67dd 100644
+--- a/src/test/cpp/xml/domtestcase.cpp
++++ b/src/test/cpp/xml/domtestcase.cpp
+@@ -190,9 +190,9 @@ public:
+                 DOMConfigurator::configure(LOG4CXX_TEST_STR("input/xml/DOMTestCase3.xml"));
+                 LOG4CXX_INFO(logger, "File name is expected to end with a superscript 3");
+ #if LOG4CXX_LOGCHAR_IS_UTF8
+-                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, 0xC2, 0xB3, 0 };
++                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, static_cast<logchar>(0xC2), static_cast<logchar>(0xB3), 0 };
+ #else
+-                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, 0xB3, 0 };
++                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, static_cast<logchar>(0xB3), 0 };
+ #endif
+                 File file;
+                 file.setPath(fname);
+@@ -209,9 +209,9 @@ public:
+                 DOMConfigurator::configure(LOG4CXX_TEST_STR("input/xml/DOMTestCase4.xml"));
+                 LOG4CXX_INFO(logger, "File name is expected to end with an ideographic 4");
+ #if LOG4CXX_LOGCHAR_IS_UTF8
+-                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, 0xE3, 0x86, 0x95, 0 };
++                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, static_cast<logchar>(0xE3), static_cast<logchar>(0x86), static_cast<logchar>(0x95), 0 };
+ #else
+-                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, 0x3195, 0 };
++                const logchar fname[] = { 0x6F, 0x75, 0x74, 0x70, 0x75, 0x74, 0x2F, 0x64, 0x6F, 0x6D, static_cast<logchar>(0x3195), 0 };
+ #endif
+                 File file;
+                 file.setPath(fname);
\ No newline at end of file
diff --git a/packages/log4cxx/package.py b/packages/log4cxx/package.py
new file mode 100644
index 0000000000000000000000000000000000000000..e792947a5330a3515799f6b502ea09720f378ba1
--- /dev/null
+++ b/packages/log4cxx/package.py
@@ -0,0 +1,43 @@
+# Copyright 2013-2023 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack.package import *
+
+
+class Log4cxx(CMakePackage):
+    """A C++ port of Log4j"""
+
+    homepage = "https://logging.apache.org/log4cxx/latest_stable/"
+    url = "https://dlcdn.apache.org/logging/log4cxx/0.12.0/apache-log4cxx-0.12.0.tar.gz"
+
+    maintainers("nicmcd")
+
+    # begin EBRAINS (added): bring upstream (ref. spack@0.21.2)
+    version("1.2.0",  sha256="09f4748aa5675ef5c0770bedbf5e00488668933c5a935a43ac5b85be2436c48a")
+    version("1.1.0",  sha256="1fc7d82697534184bc0f757348d969d24852b948f63d6b17283fd1ee29c2c28a")
+    # end EBRAINS
+    version("0.12.1", sha256="7bea5cb477f0e31c838f0e1f4f498cc3b30c2eae74703ddda923e7e8c2268d22")
+    version("0.12.0", sha256="bd5b5009ca914c8fa7944b92ea6b4ca6fb7d146f65d526f21bf8b3c6a0520e44")
+
+    variant("cxxstd", default="17", description="C++ standard", values=("11", "17"), multi=False)
+    variant("events_at_exit",
+            default=False,
+            description="Enable to use logging during the application termination"
+            )
+
+    depends_on("cmake@3.13:", type="build")
+
+    depends_on("apr-util")
+    depends_on("apr")
+    depends_on("boost+thread+system", when="cxxstd=11")
+    depends_on("zlib-api")
+    depends_on("zip")
+
+    def cmake_args(self):
+        return [
+            self.define_from_variant("CMAKE_CXX_STANDARD", "cxxstd"),
+            self.define("BUILD_TESTING", "off"),
+            self.define_from_variant("LOG4CXX_EVENTS_AT_EXIT", "events_at_exit"),
+        ]
diff --git a/packages/oppulance/package.py b/packages/oppulance/package.py
index 6db434fdf3d0509d8584df847ee8e3785046a98e..d917e96c38ed0c5737beb2cc0cbffe7515614736 100644
--- a/packages/oppulance/package.py
+++ b/packages/oppulance/package.py
@@ -21,6 +21,10 @@ class Oppulance(Package):
     depends_on('gmp')
 
     releases = [
+        {
+            'version': '8.0-a4',
+            'tag': 'ebrains-8.0-a4'
+        },
         {
             'version': '8.0-a3',
             'tag': 'ebrains-8.0-a3'
diff --git a/packages/pynn-brainscales/package.py b/packages/pynn-brainscales/package.py
index 9bbefd4dc38588c62376f58551232279d8c7d246..ee737581afebbd95bfaf56852fcd2052b74dfd69 100644
--- a/packages/pynn-brainscales/package.py
+++ b/packages/pynn-brainscales/package.py
@@ -23,6 +23,7 @@ class PynnBrainscales(build_brainscales.BuildBrainscales):
 
     maintainers = ['emuller']
 
+    version('8.0-a4',         tag='pynn-brainscales-8.0-a4')
     version('8.0-a3',         tag='pynn-brainscales-8.0-a3')
     version('8.0-a2',         tag='pynn-brainscales-8.0-a2')
     version('8.0-a1',         tag='pynn-brainscales-8.0-a1')
@@ -32,6 +33,7 @@ class PynnBrainscales(build_brainscales.BuildBrainscales):
 
     # compiler for the BrainScaleS-2 embedded processor ("PPU"); needed for
     # building/linking, at runtime and for testing
+    depends_on('oppulance@8.0-a4', when='@8.0-a4', type=('build', 'link', 'run', 'test'))
     depends_on('oppulance@8.0-a3', when='@8.0-a3', type=('build', 'link', 'run', 'test'))
     depends_on('oppulance@8.0-a2', when='@8.0-a2', type=('build', 'link', 'run', 'test'))
     depends_on('oppulance@8.0-a1', when='@8.0-a1', type=('build', 'link', 'run', 'test'))
@@ -52,7 +54,8 @@ class PynnBrainscales(build_brainscales.BuildBrainscales):
     depends_on('intel-tbb', type=('build', 'link', 'run'))  # ppu gdbserver
     depends_on('libelf', type=('build', 'link', 'run'))
     depends_on('liblockfile', type=('build', 'link', 'run'))
-    depends_on('log4cxx@0.12.1:', type=('build', 'link', 'run'))
+    depends_on('log4cxx@0.12.1:1.0', when="@:8.0-a3", type=('build', 'link', 'run'))
+    depends_on('log4cxx@1.1: +events_at_exit', when="@8.0-a4:", type=('build', 'link', 'run'))
     depends_on('pkgconfig', type=('build', 'link', 'run'))
     depends_on('psmisc', type=('run', 'test'))
     depends_on('python@3.7.0:', type=('build', 'link', 'run')) # BrainScaleS-2 only supports Python >= 3.7
diff --git a/spack.yaml b/spack.yaml
index d66c7005dbea2d54794d78200c8416661a426d9b..0bdb1d1bc3fd436aa5765fb3a441df74c2154f21 100644
--- a/spack.yaml
+++ b/spack.yaml
@@ -12,10 +12,10 @@ spack:
     - biobb-model@4.0.0
     - biobb-structure-checking@3.12.1
     - biobb-structure-utils@4.0.0
-    - hxtorch@8.0-a3
+    - hxtorch@8.0-a4
     - nest@3.7_rc1 +sonata
     - neuron@8.2.3 +mpi
-    - jaxsnn@8.0-a3
+    - jaxsnn@8.0-a4
     - py-bluepyefe@2.2.18
     - py-bluepymm@0.7.65
     - py-bluepyopt@1.13.86
@@ -54,7 +54,7 @@ spack:
     - py-tvb-multiscale@2.1.0.ebrains
     - py-tvb-storage@2.8.1
     - py-viziphant@0.4.0
-    - pynn-brainscales@8.0-a3
+    - pynn-brainscales@8.0-a4
     - r-rgsl@0.1.1
     - r-sbtabvfgen@0.1
     - r-uqsa@2.2