Dockerfile build is failing

[encryptblockr]

# docker build -t pgbouncerhero .

Sending build context to Docker daemon    254kB
Step 1/15 : FROM ruby:2.3.7
2.3.7: Pulling from library/ruby
bc9ab73e5b14: Pull complete 
193a6306c92a: Pull complete 
e5c3f8c317dc: Pull complete 
a587a86c9dcb: Pull complete 
72744d0a318b: Pull complete 
31d57ef7a684: Pull complete 
0d13d6d5ad30: Pull complete 
a1ebc7601f5a: Pull complete 
Digest: sha256:2b3f3291cd7a922129dd7c60af2abf72446ab35f0b39308d349ca42856cd2752
Status: Downloaded newer image for ruby:2.3.7
 ---> 205d0fa463d7
Step 2/15 : MAINTAINER Quentin Rousseau <contact@quent.in>
 ---> Running in 39464f0efcdf
Removing intermediate container 39464f0efcdf
 ---> 18ad85974dcd
Step 3/15 : RUN apt-get update && apt-get install -qq -y --no-install-recommends   build-essential nodejs libpq-dev
 ---> Running in 2b29456d22fe
Ign:1 http://deb.debian.org/debian stretch InRelease
Get:2 http://security.debian.org/debian-security stretch/updates InRelease [53.0 kB]
Get:3 http://deb.debian.org/debian stretch-updates InRelease [93.6 kB]
Get:4 http://deb.debian.org/debian stretch Release [118 kB]
Get:5 http://deb.debian.org/debian stretch Release.gpg [3177 B]
Get:6 http://security.debian.org/debian-security stretch/updates/main amd64 Packages [710 kB]
Get:7 http://deb.debian.org/debian stretch/main amd64 Packages [7080 kB]
Fetched 8058 kB in 2s (3126 kB/s)
Reading package lists...
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package dpkg-dev.
(Reading database ... 29290 files and directories currently installed.)
Preparing to unpack .../0-dpkg-dev_1.18.25_all.deb ...
Unpacking dpkg-dev (1.18.25) ...
Selecting previously unselected package build-essential.
Preparing to unpack .../1-build-essential_12.3_amd64.deb ...
Unpacking build-essential (12.3) ...
Preparing to unpack .../2-libpq-dev_9.6.23-0+deb9u1_amd64.deb ...
Unpacking libpq-dev (9.6.23-0+deb9u1) over (9.6.10-0+deb9u1) ...
Preparing to unpack .../3-libpq5_9.6.23-0+deb9u1_amd64.deb ...
Unpacking libpq5:amd64 (9.6.23-0+deb9u1) over (9.6.10-0+deb9u1) ...
Selecting previously unselected package libuv1:amd64.
Preparing to unpack .../4-libuv1_1.9.1-3_amd64.deb ...
Unpacking libuv1:amd64 (1.9.1-3) ...
Selecting previously unselected package nodejs.
Preparing to unpack .../5-nodejs_4.8.2~dfsg-1_amd64.deb ...
Unpacking nodejs (4.8.2~dfsg-1) ...
Setting up libuv1:amd64 (1.9.1-3) ...
Setting up dpkg-dev (1.18.25) ...
Setting up libpq5:amd64 (9.6.23-0+deb9u1) ...
Processing triggers for libc-bin (2.24-11+deb9u3) ...
Setting up libpq-dev (9.6.23-0+deb9u1) ...
Setting up nodejs (4.8.2~dfsg-1) ...
update-alternatives: using /usr/bin/nodejs to provide /usr/bin/js (js) in auto mode
Setting up build-essential (12.3) ...
Removing intermediate container 2b29456d22fe
 ---> 486776faf383
Step 4/15 : ENV INSTALL_PATH /app
 ---> Running in a97442331576
Removing intermediate container a97442331576
 ---> 149552609fd7
Step 5/15 : ENV RAILS_ENV production
 ---> Running in edf796b87721
Removing intermediate container edf796b87721
 ---> f981f143c749
Step 6/15 : ENV PGBOUNCER_DATABASE_URL postgresql://user:pass@127.0.0.1/dbname
 ---> Running in 765787fa8e69
Removing intermediate container 765787fa8e69
 ---> 7132d547ebc1
Step 7/15 : RUN mkdir -p $INSTALL_PATH
 ---> Running in 25bd3bd242fa
Removing intermediate container 25bd3bd242fa
 ---> 803b237f40f6
Step 8/15 : WORKDIR $INSTALL_PATH
 ---> Running in 96b7f9ed119b
Removing intermediate container 96b7f9ed119b
 ---> 714bb0aae309
Step 9/15 : COPY Gemfile Gemfile.lock ./
 ---> fcdaac4dca5c
Step 10/15 : RUN bundle install --binstubs
 ---> Running in 6f9c540a5a72
You must use Bundler 2 or greater with this lockfile.
The command '/bin/sh -c bundle install --binstubs' returned a non-zero code: 20

[kwent]

Should be fixed with https://github.com/kwent/pgbouncerhero-demo/blob/master/Dockerfile