diff --git a/pkgs/tools/networking/i2p/default.nix b/pkgs/tools/networking/i2p/default.nix
index b5ef06c34eaa..1ef159131af2 100644
--- a/pkgs/tools/networking/i2p/default.nix
+++ b/pkgs/tools/networking/i2p/default.nix
@@ -1,12 +1,13 @@
 { stdenv, procps, coreutils, fetchurl, jdk, jre, ant, gettext, which }:
 
 stdenv.mkDerivation rec {
-  name = "i2p-0.9.19";
+  name = "i2p-0.9.20";
   src = fetchurl {
     url = "https://github.com/i2p/i2p.i2p/archive/${name}.tar.gz";
-    sha256 = "1q9sda1a708laxf452qnzbfv7bwfwyam5n1giw2n3z3ar602i936";
+    sha256 = "10rynkl9dbnfl67ck3d7wdwz52h7354r7nbwcypsjnng4f1dmj5s";
   };
   buildInputs = [ jdk ant gettext which ];
+  patches = [ ./i2p.patch ];
   buildPhase = ''
     export JAVA_TOOL_OPTIONS="-Dfile.encoding=UTF8"
     ant preppkg-linux-only
@@ -17,15 +18,15 @@ stdenv.mkDerivation rec {
     cp -r pkg-temp/* $out
     cp installer/lib/wrapper/linux64/* $out
     sed -i $out/i2prouter -i $out/runplain.sh \
-      -e "s#%INSTALL_PATH#$out#" \
+      -e "s#uname#${coreutils}/bin/uname#" \
+      -e "s#which#${which}/bin/which#" \
+      -e "s#%gettext%#${gettext}/bin/gettext#" \
       -e "s#/usr/ucb/ps#${procps}/bin/ps#" \
       -e "s#/usr/bin/tr#${coreutils}/bin/tr#" \
+      -e "s#%INSTALL_PATH#$out#" \
       -e 's#%USER_HOME#$HOME#' \
       -e "s#%SYSTEM_java_io_tmpdir#/tmp#" \
-      -e 's#JAVA=java#JAVA=${jre}/bin/java#'
-    sed -i $out/runplain.sh \
-      -e "s#nohup \(.*Launch\) .*#\1#" \
-      -e "s#echo \$\! .*##"
+      -e "s#%JAVA%#${jre}/bin/java#"
     mv $out/runplain.sh $out/bin/i2prouter-plain
     mv $out/man $out/share/
     chmod +x $out/bin/* $out/i2psvc
diff --git a/pkgs/tools/networking/i2p/i2p.patch b/pkgs/tools/networking/i2p/i2p.patch
new file mode 100644
index 000000000000..2ae6446ed286
--- /dev/null
+++ b/pkgs/tools/networking/i2p/i2p.patch
@@ -0,0 +1,39 @@
+--- a/installer/resources/runplain.sh
++++ b/installer/resources/runplain.sh
+@@ -21,7 +21,7 @@
+ 
+ # Try using the Java binary that I2P was installed with.
+ # If it's not found, try looking in the system PATH.
+-JAVA=$(which %JAVA_HOME/bin/java || which java)
++JAVA=%JAVA%
+ 
+ if [ -z $JAVA ] || [ ! -x $JAVA ]; then
+     echo "Error: Cannot find java." >&2
+@@ -40,15 +40,4 @@
+     export JAVA_TOOL_OPTIONS="-Djava.awt.headless=true"
+ fi
+ JAVAOPTS="-Djava.net.preferIPv4Stack=${PREFERv4} -Djava.library.path=${I2P}:${I2P}/lib -Di2p.dir.base=${I2P} -DloggerFilenameOverride=logs/log-router-@.txt"
+-(
+-    nohup ${JAVA} -cp \"${CP}\" ${JAVAOPTS} net.i2p.router.RouterLaunch > /dev/null 2>&1
+-) &
+-PID=$!
+-
+-if [ ! -z $PID ] && kill -0 $PID > /dev/null 2>&1 ; then
+-    echo "I2P started [$PID]" >&2
+-    echo $PID > "${I2PTEMP}/router.pid"
+-else
+-    echo "I2P failed to start." >&2
+-    exit 1
+-fi
++${JAVA} -cp \"${CP}\" ${JAVAOPTS} net.i2p.router.RouterLaunch
+--- a/installer/resources/i2prouter
++++ b/installer/resources/i2prouter
+@@ -49,7 +49,7 @@
+ 
+ # gettext - we look for it in the path
+ # fallback to echo is below, we can't set it to echo here.
+-GETTEXT=$(which gettext > /dev/null 2>&1)
++GETTEXT=%gettext%
+ 
+ # Where to install the systemd service
+ SYSTEMD_SERVICE="/etc/systemd/system/${APP_NAME}.service"