nginx doesn't serve static assets in Rails 4.1.8 + Spree - ruby-on-rails-4

Question

I have a problem with Nginx - Unicorn - Rails 4.1 and Spree production setup, according to this tutorial.
The site shows up at the ip address (I need to get a domain yet). But it seems assets are not readable. This is the error log from /var/log/nginx/spree_zaza_error.log
2014/12/21 23:06:22 [error] 13598#0: *12 open() "/home/user/workplace/spree_zaza/public/assets/spree.js" failed (2: No such file or directory), client: 213.230.83.135, server: , request: "GET /assets/spree.js?body=1 HTTP/1.1", host: "212.111.40.25", referrer: "http://212.111.40.25/t/brand/apache"
2014/12/21 23:06:22 [error] 13598#0: *11 open() "/home/user/workplace/spree_zaza/public/assets/spree/frontend/checkout.js" failed (2: No such file or directory), client: 213.230.83.135, server: , request: "GET /assets/spree/frontend/checkout.js?body=1 HTTP/1.1", host: "212.111.40.25", referrer: "http://212.111.40.25/t/brand/apache"
2014/12/21 23:06:22 [error] 13598#0: *11 open() "/home/user/workplace/spree_zaza/public/assets/logo/spree_50.png" failed (2: No such file or directory), client: 213.230.83.135, server: , request: "GET /assets/logo/spree_50.png HTTP/1.1", host: "212.111.40.25", referrer: "http://212.111.40.25/t/brand/apache"
Although I ran rake assets:precompile and there are a bunch of hashed and gzipped files, some files don't exist, but for example assests/logo/spree_50 is there.
This is my /etc/nginx/sites-enabled/spree_zaza file:
upstream spree_zaza {
# fail_timeout=0 means we always retry an upstream even if it failed
# to return a good HTTP response (in case the Unicorn master nukes a
# single worker for timing out).
server unix:/tmp/spree_zaza.socket fail_timeout=0;
}
server {
# if you're running multiple servers, instead of "default" you should
# put your main domain name here
listen 80 default;
# you could put a list of other domain names this application answers
#server_name [your server's address];
root /home/user/workplace/spree_zaza/public;
access_log /var/log/nginx/spree_zaza_access.log;
error_log /var/log/nginx/spree_zaza_error.log;
rewrite_log on;
location / {
#all requests are sent to the UNIX socket
proxy_pass http://spree_zaza;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
client_max_body_size 10m;
client_body_buffer_size 128k;
proxy_connect_timeout 90;
proxy_send_timeout 90;
proxy_read_timeout 90;
proxy_buffer_size 4k;
proxy_buffers 4 32k;
proxy_busy_buffers_size 64k;
proxy_temp_file_write_size 64k;
}
# if the request is for a static resource, nginx should serve it directly
# and add a far future expires header to it, making the browser
# cache the resource and navigate faster over the website
location ~ ^/(system|assets|spree)/ {
root /home/user/workplace/spree_zaza/public;
expires max;
break;
}
}
And the following is /home/user/workplace/spree_zaza/config/unicorn.rb:
# config/unicorn.rb
# Set environment to development unless something else is specified
#env = ENV["RAILS_ENV"] || "development"
#env = ENV["RAILS_ENV"] || "production"
env = "production"
# See http://unicorn.bogomips.org/Unicorn/Configurator.html for complete documentation.
worker_processes 3
# listen on both a Unix domain socket and a TCP port,
# we use a shorter backlog for quicker failover when busy
listen "/tmp/spree_zaza.socket", backlog: 64
# Preload our app for more speed
preload_app true
# nuke workers after 30 seconds instead of 60 seconds (the default)
timeout 30
pid "/tmp/unicorn.spree_zaza.pid"
# Production specific settings
if env == "production"
# Help ensure your application will always spawn in the symlinked
# "current" directory that Capistrano sets up.
working_directory "/home/user/workplace/spree_zaza"
# feel free to point this anywhere accessible on the filesystem user 'spree'
shared_path = "/home/user/workplace/spree_zaza"
stderr_path "#{shared_path}/log/unicorn.stderr.log"
stdout_path "#{shared_path}/log/unicorn.stdout.log"
end
before_fork do |server, worker|
# the following is highly recomended for Rails + "preload_app true"
# as there's no need for the master process to hold a connection
if defined?(ActiveRecord::Base)
ActiveRecord::Base.connection.disconnect!
end
# Before forking, kill the master process that belongs to the .oldbin PID.
# This enables 0 downtime deploys.
old_pid = "/tmp/unicorn.spree_zaza.pid.oldbin"
if File.exists?(old_pid) && server.pid != old_pid
begin
Process.kill("QUIT", File.read(old_pid).to_i)
rescue Errno::ENOENT, Errno::ESRCH
# someone else did our job for us
end
end
end
after_fork do |server, worker|
# the following is *required* for Rails + "preload_app true"
if defined?(ActiveRecord::Base)
ActiveRecord::Base.establish_connection
end
# if preload_app is true, then you may also want to check and
# restart any other shared sockets/descriptors such as Memcached,
# and Redis. TokyoCabinet file handles are safe to reuse
# between any number of forked children (assuming your kernel
# correctly implements pread()/pwrite() system calls)
end
Also, I uncommented the following switch in config/environments/production.rb
config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect'
Thanks for your ideas.