Try to use Alpine Linux as the base image

Dockerfile

-FROM debian:jessie
+FROM alpine:3.4
 
 # Install runtime packages
-RUN apt-get update && apt-get install -y gnutls-bin iptables libev4 libnl-route-3-200 libprotobuf-c1 libseccomp2 libwrap0 openssl --no-install-recommends && rm -rf /var/lib/apt/lists/* 
-
-# NOT FOUND?
-# 		libfreeradius-client-dev liblz4-dev libsystemd-daemon-dev
-# Use included:
-# 		libhttp-parser-dev libpcl1-dev libtalloc-dev
+RUN apk update && apk add diffutils gawk gnutls gnutls-utils iptables libintl libnl linux-pam lz4 openssl readline sed
 
 RUN buildDeps=" \
-		autoconf \
-		autogen \
-		ca-certificates \
 		curl \
+		g++ \
 		gcc \
+		gnutls-dev \
 		gperf \
-		libev-dev \
-		libgnutls28-dev \
-		libnl-route-3-dev \
-		libpam0g-dev \
-		libprotobuf-c-dev \
-		libreadline-dev \
-		libseccomp-dev \
-		libwrap0-dev \
+		gpgme \
+		linux-headers \
+		lz4-dev \
 		make \
-		pkg-config \
-		xz-utils \
+		readline-dev \
+		tar \
+		xz \
 	"; \
 	set -x \
-	&& apt-get update && apt-get install -y $buildDeps --no-install-recommends && rm -rf /var/lib/apt/lists/* \
-	&& LZ4_VERSION=`curl "https://github.com/Cyan4973/lz4/releases/latest" | sed -n 's/^.*tag\/\(.*\)".*/\1/p'` \
-	&& curl -SL "https://github.com/Cyan4973/lz4/archive/$LZ4_VERSION.tar.gz" -o lz4.tar.gz \
-	&& mkdir -p /usr/src/lz4 \
-	&& tar -xf lz4.tar.gz -C /usr/src/lz4 --strip-components=1 \
-	&& rm lz4.tar.gz \
-	&& cd /usr/src/lz4 \
-	&& make -j"$(nproc)" \
-	&& make install \
+	&& apk add $buildDeps \
 	&& OC_VERSION=`curl "http://www.infradead.org/ocserv/download.html" | sed -n 's/^.*version is <b>\(.*$\)/\1/p'` \
 	&& curl -SL "ftp://ftp.infradead.org/pub/ocserv/ocserv-$OC_VERSION.tar.xz" -o ocserv.tar.xz \
 	&& curl -SL "ftp://ftp.infradead.org/pub/ocserv/ocserv-$OC_VERSION.tar.xz.sig" -o ocserv.tar.xz.sig \
@@ -52,9 +34,8 @@ RUN buildDeps=" \
 	&& mkdir -p /etc/ocserv \
 	&& cp /usr/src/ocserv/doc/sample.config /etc/ocserv/ocserv.conf \
 	&& cd / \
-	&& rm -fr /usr/src/lz4 \
 	&& rm -fr /usr/src/ocserv \
-	&& apt-get purge -y --auto-remove $buildDeps
+	&& apk del $buildDeps
 
 # Setup config
 COPY cn-no-route.txt /tmp/