diff --git a/.travis.yml b/.travis.yml
index 8444c0721..4032623a4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,10 +7,10 @@ install:
   - cp config/config.yml.example config/config.yml
   - cp db/schema.rb.example db/schema.rb
   - docker-compose build
-  - docker-compose run web sleep 10
-  - docker-compose run web bash -c "rake db:setup"
-  - docker-compose run web bash -c "rake db:migrate"
+  - docker-compose run web bash -l -c "sleep 10"
+  - docker-compose run web bash -l -c "rake db:setup"
+  - docker-compose run web bash -l -c "rake db:migrate"
   - docker-compose run web bower install --allow-root
 
 script:
-  - docker-compose run web bash -c "rake test"
+  - docker-compose run web bash -l -c "rake test"
diff --git a/Dockerfile b/Dockerfile
index 6f1a4153d..b6eadad88 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,9 +1,7 @@
 # Dockerfile # Mapknitter
 # https://github.com/publiclab/mapknitter/
 
-FROM ruby:2.4.4-stretch
-MAINTAINER Sebastian Silva "sebastian@fuentelibre.org"
-
+FROM debian:buster
 LABEL This image deploys Mapknitter!
 
 # Set correct environment variables.
@@ -11,16 +9,35 @@ RUN mkdir -p /app
 ENV HOME /root
 
 # Install dependencies
-RUN curl -sL https://deb.nodesource.com/setup_8.x | bash -
-RUN apt-get update -qq && apt-get install -y bundler default-libmysqlclient-dev ruby-rmagick libfreeimage3 libfreeimage-dev ruby-dev gdal-bin python-gdal curl libcurl4-openssl-dev libssl-dev zip nodejs ##ALSO TRIED: ruby-pg
+RUN apt-get update -qq && apt-get install -y \
+  bundler ruby-rmagick libfreeimage3 \
+  libfreeimage-dev zip nodejs gdal-bin \
+  curl g++ gcc autoconf automake bison \
+  libc6-dev libffi-dev libgdbm-dev \
+  libncurses5-dev libsqlite3-dev libtool \
+  libyaml-dev make pkg-config sqlite3 \
+  zlib1g-dev libgmp-dev libreadline-dev libssl-dev \
+  procps libmariadb-dev-compat libmariadb-dev git python-gdal \
+  imagemagick
+
+# Ruby
+RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB && curl -sSL https://get.rvm.io | bash -s stable && usermod -a -G rvm root
+RUN /bin/bash -l -c ". /etc/profile.d/rvm.sh && rvm install 2.4.4 && rvm use 2.4.4 --default"
+
+RUN curl -sL https://deb.nodesource.com/setup_8.x | bash - && apt-get install -y npm
 RUN npm install -g bower
 
+
 # Install bundle of gems
+SHELL [ "/bin/bash", "-l", "-c" ]
 WORKDIR /tmp
 ADD Gemfile /tmp/Gemfile
 ADD Gemfile.lock /tmp/Gemfile.lock
 RUN bundle install
 
+# HOTFIX Workaround for mysql2 gem incompatibility with libmariadb-dev
+RUN sed -i "s/ LONG_PASSWORD |//g" /usr/local/rvm/gems/ruby-*/gems/mysql2-*/lib/mysql2/client.rb
+
 # Add the Rails app
 WORKDIR /app
 ADD . /app
diff --git a/app/models/map.rb b/app/models/map.rb
index a55e6a8ea..fabfaea1c 100755
--- a/app/models/map.rb
+++ b/app/models/map.rb
@@ -202,164 +202,23 @@ def grouped_images_histogram(binsize)
     hist
   end
 
-  def run_export(user,resolution)
-    begin
-      unless export = self.export
-        export = Export.new({
-          :map_id => self.id
-        })
-      end
-      export.user_id = user.id if user
-      export.status = 'starting'
-      export.tms = false
-      export.geotiff = false
-      export.zip = false
-      export.jpg = false
-      export.save
-
-      directory = "#{Rails.root}/public/warps/"+self.slug+"/"
-      stdin, stdout, stderr = Open3.popen3('rm -r '+directory.to_s)
-      puts stdout.readlines
-      puts stderr.readlines
-      stdin, stdout, stderr = Open3.popen3("rm -r #{Rails.root}/public/tms/#{self.slug}")
-      puts stdout.readlines
-      puts stderr.readlines
-
-      puts '> averaging scales'
-      pxperm = 100/(resolution).to_f || self.average_scale # pixels per meter
-
-      puts '> distorting warpables'
-    
-      origin = self.distort_warpables(pxperm, self.placed_warpables, self.latest_export)
-      warpable_coords = origin.pop
-
-      export = self.export
-      export.status = 'compositing'
-      export.save
-
-      puts '> generating composite tiff'
-      composite_location = self.generate_composite_tiff(warpable_coords,origin)
-
-      info = (`identify -quiet -format '%b,%w,%h' #{composite_location}`).split(',')
-      puts info
-
-      export = self.export
-      if info[0] != ''
-        export.geotiff = true
-        export.size = info[0]
-        export.width = info[1]
-        export.height = info[2]
-        export.cm_per_pixel = 100.0000/pxperm
-        export.status = 'tiling'
-        export.save
-      end
-
-      puts '> generating tiles'
-      export = self.export
-      export.tms = true if self.generate_tiles
-      export.status = 'zipping tiles'
-      export.save
-
-      puts '> zipping tiles'
-      export = self.export
-      export.zip = true if self.zip_tiles
-      export.status = 'creating jpg'
-      export.save
-
-      puts '> generating jpg'
-      export = self.export
-      export.jpg = true if self.generate_jpg
-      export.status = 'complete'
-      export.save
-
-    rescue SystemCallError
-      export = self.export
-      export.status = 'failed'
-      export.save
-    end
-    return export.status
-  end
-
-  # distort all warpables, returns upper left corner coords in x,y
-  def distort_warpables(scale, warpables, export)
-
-    puts '> generating geotiffs of each warpable in GDAL'
-    lowest_x=0
-    lowest_y=0
-    warpable_coords = []
-    current = 0
-    warpables.each do |warpable|
-     current += 1
-
-     export.status = 'warping '+current.to_s+' of '+warpables.length.to_s
-     puts 'warping '+current.to_s+' of '+warpables.length.to_s
-     export.save
-
-     my_warpable_coords = warpable.generate_perspectival_distort(scale,self.slug)
-     puts '- '+my_warpable_coords.to_s
-     warpable_coords << my_warpable_coords
-     lowest_x = my_warpable_coords.first if (my_warpable_coords.first < lowest_x || lowest_x == 0)
-     lowest_y = my_warpable_coords.last if (my_warpable_coords.last < lowest_y || lowest_y == 0)
-    end
-    [lowest_x,lowest_y,warpable_coords]
-  end
-
-  # generate a tiff from all warpable images in this set
-  def generate_composite_tiff(coords,origin)
-    directory = "public/warps/"+self.slug+"/"
-    composite_location = directory+self.slug+'-geo.tif'
-    geotiffs = ''
-    minlat = nil
-    minlon = nil
-    maxlat = nil
-    maxlon = nil
-    self.placed_warpables.each do |warpable|
-      warpable.nodes_array.each do |n|
-        minlat = n.lat if minlat == nil || n.lat < minlat
-        minlon = n.lon if minlon == nil || n.lon < minlon
-        maxlat = n.lat if maxlat == nil || n.lat > maxlat
-        maxlon = n.lon if maxlon == nil || n.lon > maxlon
-      end
-    end
-    first = true
-    # sort by area; this would be overridden by a provided order
-    warpables = self.placed_warpables.sort{|a,b|b.poly_area <=> a.poly_area}
-    warpables.each do |warpable|
-      geotiffs += ' '+directory+warpable.id.to_s+'-geo.tif'
-      if first
-        gdalwarp = "gdalwarp -te "+minlon.to_s+" "+minlat.to_s+" "+maxlon.to_s+" "+maxlat.to_s+" "+directory+warpable.id.to_s+'-geo.tif '+directory+self.slug+'-geo.tif'
-        first = false
-      else
-        gdalwarp = "gdalwarp "+directory+warpable.id.to_s+'-geo.tif '+directory+self.slug+'-geo.tif'
-      end
-      puts gdalwarp
-      system(Gdal.ulimit+gdalwarp)
+  # we'll eventually replace this with a JavaScript call to initiate an external export process:
+  def run_export(user, resolution)
+    key = APP_CONFIG ? APP_CONFIG["google_maps_api_key"] : "AIzaSyAOLUQngEmJv0_zcG1xkGq-CXIPpLQY8iQ"
+    unless export
+      export = Export.new({
+        :map_id => id
+      })
     end
-    composite_location
-  end
-
-  # generates a tileset at Rails.root.to_s/public/tms/<map_name>/
-  def generate_tiles
-    google_api_key = APP_CONFIG["google_maps_api_key"]
-    gdal2tiles = 'gdal2tiles.py -k -t "'+self.slug+'" -g "'+google_api_key+'" '+Rails.root.to_s+'/public/warps/'+self.slug+'/'+self.slug+'-geo.tif '+Rails.root.to_s+'/public/tms/'+self.slug+"/"
-#    puts gdal2tiles
-#    puts system('which gdal2tiles.py')
-    system(Gdal.ulimit+gdal2tiles)
-  end
-
-  # zips up tiles at Rails.root/public/tms/<map_name>.zip
-  def zip_tiles
-    rmzip = 'cd public/tms/ && rm '+self.slug+'.zip && cd ../../'
-    system(Gdal.ulimit+rmzip)
-    zip = 'cd public/tms/ && zip -rq '+self.slug+'.zip '+self.slug+'/ && cd ../../'
-    #    puts zip
-    #    puts system('which gdal2tiles.py')
-    system(Gdal.ulimit+zip)
-  end
-
-  def generate_jpg
-    imageMagick = 'convert -background white -flatten '+Rails.root.to_s+'/public/warps/'+self.slug+'/'+self.slug+'-geo.tif '+Rails.root.to_s+'/public/warps/'+self.slug+'/'+self.slug+'.jpg'
-    system(Gdal.ulimit+imageMagick)
+    Exporter.run_export(user, 
+      resolution,
+      self.export,
+      self.id,
+      self.slug,
+      Rails.root.to_s,
+      self.average_scale,
+      self.placed_warpables,
+      key)
   end
 
   def after_create
diff --git a/app/models/warpable.rb b/app/models/warpable.rb
index 82c77eb44..4ec8059e2 100755
--- a/app/models/warpable.rb
+++ b/app/models/warpable.rb
@@ -141,203 +141,9 @@ def url=(uri)
     self.uploaded_data = io
   end
 
-  # pixels per meter = pxperm 
-  def generate_perspectival_distort(pxperm,path)
-    require 'net/http'
-    
-    # everything in -working/ can be deleted; 
-    # this is just so we can use the files locally outside of s3
-    working_directory = self.working_directory(path)
-    Dir.mkdir(working_directory) unless (File.exist?(working_directory) && File.directory?(working_directory))
-    local_location = working_directory+self.id.to_s+'-'+self.image_file_name.to_s
-
-    directory = self.warps_directory(path)
-    Dir.mkdir(directory) unless (File.exist?(directory) && File.directory?(directory))
-    completed_local_location = directory+self.id.to_s+'.png'
-
-    # everything -masked.png can be deleted
-    masked_local_location = directory+self.id.to_s+'-masked.png'
-    # everything -mask.png can be deleted
-    mask_location = directory+self.id.to_s+'-mask.png'
-    #completed_local_location = directory+self.id.to_s+'.tif'
-    # know everything -unwarped can be deleted
-    geotiff_location = directory+self.id.to_s+'-geo-unwarped.tif'
-    # everything -geo WITH AN ID could be deleted, but there is a feature request to preserve these
-    warped_geotiff_location = directory+self.id.to_s+'-geo.tif'
-
-    northmost = self.nodes_array.first.lat
-    southmost = self.nodes_array.first.lat
-    westmost = self.nodes_array.first.lon
-    eastmost = self.nodes_array.first.lon
-
-    self.nodes_array.each do |node|
-      northmost = node.lat if node.lat > northmost
-      southmost = node.lat if node.lat < southmost
-      westmost = node.lon if node.lon < westmost
-      eastmost = node.lon if node.lon > eastmost
-    end
-
-    # puts northmost.to_s+','+southmost.to_s+','+westmost.to_s+','+eastmost.to_s
-    
-    scale = 20037508.34    
-    y1 = pxperm*Cartagen.spherical_mercator_lat_to_y(northmost,scale)
-    x1 = pxperm*Cartagen.spherical_mercator_lon_to_x(westmost,scale)
-    y2 = pxperm*Cartagen.spherical_mercator_lat_to_y(southmost,scale)
-    x2 = pxperm*Cartagen.spherical_mercator_lon_to_x(eastmost,scale)
-    # puts x1.to_s+','+y1.to_s+','+x2.to_s+','+y2.to_s
-
-    # should determine if it's stored in s3 or locally:
-    if (self.image.url[0..3] == 'http')
-      Net::HTTP.start('s3.amazonaws.com') { |http|
-      #Net::HTTP.start('localhost') { |http|
-        puts (self.image.url)
-        resp = http.get(self.image.url)
-        open(local_location, "wb") { |file|
-          file.write(resp.body)
-        }
-      }
-    else
-      require "fileutils"
-      FileUtils.cp(Rails.root.to_s+'/public'+self.image.to_s,local_location)
-    end
-
-    points = ""
-    maskpoints = ""
-    coordinates = ""
-    first = true
- 
-#EXIF orientation values: 
-#Value  0th Row  0th Column
-#1  top  left side
-#2  top  right side
-#3  bottom  right side
-#4  bottom  left side
-#5  left side  top
-#6  right side  top
-#7  right side  bottom
-#8  left side  bottom
-  
-  rotation = (`identify -format %[exif:Orientation] #{local_location}`).to_i  
-  #stdin, stdout, stderr = Open3.popen3('identify -format %[exif:Orientation] #{local_location}')
-  #rotation = stdout.readlines.first.to_s.to_i
-  #puts stderr.readlines
-
-    if rotation == 6
-      puts 'rotated CCW'
-      source_corners = source_corners = [[0,self.height],[0,0],[self.width,0],[self.width,self.height]]
-    elsif rotation == 8
-      puts 'rotated CW'
-      source_corners = [[self.width,0],[self.width,self.height],[0,self.height],[0,0]]
-    elsif rotation == 3
-      puts 'rotated 180 deg'
-      source_corners = [[self.width,self.height],[0,self.height],[0,0],[self.width,0]]
-    else
-      source_corners = [[0,0],[self.width,0],[self.width,self.height],[0,self.height]]
-    end
-
-    maxdimension = 0
-
-    self.nodes_array.each do |node|
-      corner = source_corners.shift
-      nx1 = corner[0]
-      ny1 = corner[1]
-      nx2 = -x1+(pxperm*Cartagen.spherical_mercator_lon_to_x(node.lon,scale))
-      ny2 = y1-(pxperm*Cartagen.spherical_mercator_lat_to_y(node.lat,scale))
- 
-      points = points + '  ' unless first
-      maskpoints = maskpoints + ' ' unless first
-      points = points + nx1.to_s + ',' + ny1.to_s + ' ' + nx2.to_i.to_s + ',' + ny2.to_i.to_s
-      maskpoints = maskpoints + nx2.to_i.to_s + ',' + ny2.to_i.to_s
-      first = false
-      # we need to find an origin; find northwestern-most point
-      coordinates = coordinates+' -gcp '+nx2.to_s+', '+ny2.to_s+', '+node.lon.to_s + ', ' + node.lat.to_s
-      
-      # identify largest dimension to set canvas size for ImageMagick:
-      maxdimension = nx1.to_i if maxdimension < nx1.to_i
-      maxdimension = ny1.to_i if maxdimension < ny1.to_i
-      maxdimension = nx2.to_i if maxdimension < nx2.to_i
-      maxdimension = ny2.to_i if maxdimension < ny2.to_i
-    end
-
-    # close mask polygon:
-    maskpoints = maskpoints + ' '
-      nx2 = -x1+(pxperm*Cartagen.spherical_mercator_lon_to_x(self.nodes_array.first.lon,scale))
-      ny2 = y1-(pxperm*Cartagen.spherical_mercator_lat_to_y(self.nodes_array.first.lat,scale))
-    maskpoints = maskpoints + nx2.to_i.to_s + ',' + ny2.to_i.to_s
-
-    height = (y1-y2).to_i.to_s
-    width = (-x1+x2).to_i.to_s
-
-  # http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=11319
-  # http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=8764
-  # read about equalization 
-  # -equalize
-  # -contrast-stretch 0
-
-    imageMagick = "convert "
-    imageMagick += "-contrast-stretch 0 "
-    imageMagick += local_location+" "
-    imageMagick += "-crop "+maxdimension.to_i.to_s+"x"+maxdimension.to_i.to_s+"+0+0! "
-    imageMagick += "-flatten "
-    imageMagick += "-distort Perspective '"+points+"' "
-    imageMagick += "-flatten "
-    if width > height
-  imageMagick += "-crop "+width+"x"+width+"+0+0\! "
-    else
-  imageMagick += "-crop "+height+"x"+height+"+0+0\! "
-    end
-    imageMagick += "+repage "
-    imageMagick += completed_local_location
-    puts imageMagick
-  system(Gdal.ulimit+imageMagick)
-
-    # create a mask (later we can blur edges here)
-    imageMagick2 = 'convert +antialias '
-    if width > height
-  imageMagick2 += "-size "+width+"x"+width+" "
-    else
-  imageMagick2 += "-size "+height+"x"+height+" "
-    end
-  # attempt at blurred edges in masking, but I've given up, as gdal_merge doesn't seem to respect variable-opacity alpha channels
-      imageMagick2 += ' xc:none -draw "fill black stroke red stroke-width 30 polyline '
-      imageMagick2 += maskpoints + '" '
-      imageMagick2 += ' -alpha set -channel A -transparent red -blur 0x8 -channel R -evaluate set 0 +channel '+mask_location
-    #imageMagick2 += ' xc:none -draw "fill black stroke none polyline '
-    #imageMagick2 += maskpoints + '" '
-    #imageMagick2 += ' '+mask_location
-    puts imageMagick2
-  system(Gdal.ulimit+imageMagick2)
-
-    imageMagick3 = 'composite '+mask_location+' '+completed_local_location+' -compose DstIn -alpha Set '+masked_local_location
-    puts imageMagick3
-  system(Gdal.ulimit+imageMagick3)
-
-    gdal_translate = "gdal_translate -of GTiff -a_srs EPSG:4326 "+coordinates+'  -co "TILED=NO" '+masked_local_location+' '+geotiff_location
-    puts gdal_translate
-  system(Gdal.ulimit+gdal_translate)
- 
-    #gdalwarp = 'gdalwarp -srcnodata "255" -dstnodata 0 -cblend 30 -of GTiff -t_srs EPSG:4326 '+geotiff_location+' '+warped_geotiff_location
-    gdalwarp = 'gdalwarp -of GTiff -t_srs EPSG:4326 '+geotiff_location+' '+warped_geotiff_location
-    puts gdalwarp
-  system(Gdal.ulimit+gdalwarp)
-
-    # deletions could happen here; do it in distinct method so we can run it independently
-    self.delete_temp_files(path)
-
-    [x1,y1]
-  end
-
-  def working_directory(path)
-    "public/warps/"+path+"-working/"
-  end
-
-  def warps_directory(path)
-    "public/warps/"+path+"/"
-  end
-
-  def delete_temp_files(path)
-    system('rm -r '+self.working_directory(path))
-    system('rm '+self.warps_directory(path)+'*.png')
+  # TODO: simplify/reduce # of parameters needed here:
+  def generate_perspectival_distort(pxperm, path)
+    Exporter.generate_perspectival_distort(pxperm, path, nodes_array, id, image_file_name, image, height, width)
   end
 
   def user_id
diff --git a/config/initializers/column_definition.rb b/config/initializers/column_definition.rb
index ec8438adf..feca93639 100644
--- a/config/initializers/column_definition.rb
+++ b/config/initializers/column_definition.rb
@@ -15,7 +15,11 @@
 # Read more at https://github.com/publiclab/mapknitter/pull/323
 
 class ActiveRecord::ConnectionAdapters::ColumnDefinition
-  def sql_type
-    type.to_sym == :primary_key ? 'int(11) auto_increment PRIMARY KEY' : base.type_to_sql(type.to_sym, limit, precision, scale) rescue type
+
+  if ActiveRecord::Base.connection.adapter_name != 'sqlite3' && ActiveRecord::Base.connection.adapter_name != 'SQLite'
+    def sql_type
+      type.to_sym == :primary_key ? 'int(11) auto_increment PRIMARY KEY' : base.type_to_sql(type.to_sym, limit, precision, scale) rescue type
+    end 
   end 
-end
\ No newline at end of file
+
+end
diff --git a/config/initializers/mysql2_adapter.rb b/config/initializers/mysql2_adapter.rb
new file mode 100644
index 000000000..801c43982
--- /dev/null
+++ b/config/initializers/mysql2_adapter.rb
@@ -0,0 +1,5 @@
+# https://github.com/peatio/peatio/issues/590#issuecomment-352550396
+require 'active_record/connection_adapters/mysql2_adapter'
+class ActiveRecord::ConnectionAdapters::Mysql2Adapter
+  NATIVE_DATABASE_TYPES[:primary_key] = "int(11) auto_increment PRIMARY KEY"
+end
diff --git a/lib/exporter-deps.sh b/lib/exporter-deps.sh
new file mode 100644
index 000000000..fb262e8ae
--- /dev/null
+++ b/lib/exporter-deps.sh
@@ -0,0 +1 @@
+sudo apt-get install gdal-bin python-gdal curl libcurl4-openssl-dev libssl-dev zip libmysqlclient-dev imagemagick ruby-rmagick libfreeimage3 libfreeimage-dev ruby-dev libmagickcore-dev libmagickwand-dev
diff --git a/lib/exporter.rb b/lib/exporter.rb
new file mode 100644
index 000000000..057cdf50e
--- /dev/null
+++ b/lib/exporter.rb
@@ -0,0 +1,370 @@
+class Exporter
+
+  def self.ulimit
+    # use ulimit to restrict to 7200 CPU seconds and 5gb virtual memory, and 5gB file storage:
+    #"ulimit -t 7200 && ulimit -v 5000000 && ulimit -f 5000000 && "
+    "ulimit -t 14400 && ulimit -v 5000000 && ulimit -f 10000000 && nice -n 19 "
+  end
+
+  def self.get_working_directory(path)
+    "public/warps/" + path + "-working/"
+  end
+
+  def self.warps_directory(path)
+    "public/warps/" + path + "/"
+  end
+
+  def self.delete_temp_files(path)
+    system('rm -r ' + get_working_directory(path))
+    system('rm ' + warps_directory(path) + '*.png')
+  end
+
+  ########################
+  ## Run on each image:
+
+  # pixels per meter = pxperm 
+  def self.generate_perspectival_distort(pxperm, path, nodes_array, id, image_file_name, image, height, width)
+    require 'net/http'
+    
+    # everything in -working/ can be deleted; 
+    # this is just so we can use the files locally outside of s3
+    working_directory = get_working_directory(path)
+    Dir.mkdir(working_directory) unless (File.exists?(working_directory) && File.directory?(working_directory))
+    local_location = working_directory+id.to_s+'-'+image_file_name.to_s
+
+    directory = warps_directory(path)
+    Dir.mkdir(directory) unless (File.exists?(directory) && File.directory?(directory))
+    completed_local_location = directory+id.to_s+'.png'
+
+    # everything -masked.png can be deleted
+    masked_local_location = directory+id.to_s+'-masked.png'
+    # everything -mask.png can be deleted
+    mask_location = directory+id.to_s+'-mask.png'
+    #completed_local_location = directory+id.to_s+'.tif'
+    # know everything -unwarped can be deleted
+    geotiff_location = directory+id.to_s+'-geo-unwarped.tif'
+    # everything -geo WITH AN ID could be deleted, but there is a feature request to preserve these
+    warped_geotiff_location = directory+id.to_s+'-geo.tif'
+
+    northmost = nodes_array.first.lat
+    southmost = nodes_array.first.lat
+    westmost = nodes_array.first.lon
+    eastmost = nodes_array.first.lon
+
+    nodes_array.each do |node|
+      northmost = node.lat if node.lat > northmost
+      southmost = node.lat if node.lat < southmost
+      westmost = node.lon if node.lon < westmost
+      eastmost = node.lon if node.lon > eastmost
+    end
+
+    # puts northmost.to_s+','+southmost.to_s+','+westmost.to_s+','+eastmost.to_s
+    
+    scale = 20037508.34    
+    y1 = pxperm*Cartagen.spherical_mercator_lat_to_y(northmost,scale)
+    x1 = pxperm*Cartagen.spherical_mercator_lon_to_x(westmost,scale)
+    y2 = pxperm*Cartagen.spherical_mercator_lat_to_y(southmost,scale)
+    x2 = pxperm*Cartagen.spherical_mercator_lon_to_x(eastmost,scale)
+    # puts x1.to_s+','+y1.to_s+','+x2.to_s+','+y2.to_s
+
+    # should determine if it's stored in s3 or locally:
+    if (image.url[0..3] == 'http')
+      Net::HTTP.start('s3.amazonaws.com') { |http|
+      #Net::HTTP.start('localhost') { |http|
+        puts (image.url)
+        resp = http.get(image.url)
+        open(local_location, "wb") { |file|
+          file.write(resp.body)
+        }
+      }
+    else
+      require "fileutils"
+      FileUtils.cp(Rails.root.to_s+'/public'+image.to_s,local_location)
+    end
+
+    points = ""
+    maskpoints = ""
+    coordinates = ""
+    first = true
+ 
+#EXIF orientation values: 
+#Value  0th Row  0th Column
+#1  top  left side
+#2  top  right side
+#3  bottom  right side
+#4  bottom  left side
+#5  left side  top
+#6  right side  top
+#7  right side  bottom
+#8  left side  bottom
+  
+  rotation = (`identify -format %[exif:Orientation] #{local_location}`).to_i  
+  #stdin, stdout, stderr = Open3.popen3('identify -format %[exif:Orientation] #{local_location}')
+  #rotation = stdout.readlines.first.to_s.to_i
+  #puts stderr.readlines
+
+    if rotation == 6
+      puts 'rotated CCW'
+      source_corners = source_corners = [[0,height],[0,0],[width,0],[width,height]]
+    elsif rotation == 8
+      puts 'rotated CW'
+      source_corners = [[width,0],[width,height],[0,height],[0,0]]
+    elsif rotation == 3
+      puts 'rotated 180 deg'
+      source_corners = [[width,height],[0,height],[0,0],[width,0]]
+    else
+      source_corners = [[0,0],[width,0],[width,height],[0,height]]
+    end
+
+    maxdimension = 0
+
+    nodes_array.each do |node|
+      corner = source_corners.shift
+      nx1 = corner[0]
+      ny1 = corner[1]
+      nx2 = -x1+(pxperm*Cartagen.spherical_mercator_lon_to_x(node.lon,scale))
+      ny2 = y1-(pxperm*Cartagen.spherical_mercator_lat_to_y(node.lat,scale))
+ 
+      points = points + '  ' unless first
+      maskpoints = maskpoints + ' ' unless first
+      points = points + nx1.to_s + ',' + ny1.to_s + ' ' + nx2.to_i.to_s + ',' + ny2.to_i.to_s
+      maskpoints = maskpoints + nx2.to_i.to_s + ',' + ny2.to_i.to_s
+      first = false
+      # we need to find an origin; find northwestern-most point
+      coordinates = coordinates+' -gcp '+nx2.to_s+', '+ny2.to_s+', '+node.lon.to_s + ', ' + node.lat.to_s
+      
+      # identify largest dimension to set canvas size for ImageMagick:
+      maxdimension = nx1.to_i if maxdimension < nx1.to_i
+      maxdimension = ny1.to_i if maxdimension < ny1.to_i
+      maxdimension = nx2.to_i if maxdimension < nx2.to_i
+      maxdimension = ny2.to_i if maxdimension < ny2.to_i
+    end
+
+    # close mask polygon:
+    maskpoints = maskpoints + ' '
+      nx2 = -x1+(pxperm*Cartagen.spherical_mercator_lon_to_x(nodes_array.first.lon,scale))
+      ny2 = y1-(pxperm*Cartagen.spherical_mercator_lat_to_y(nodes_array.first.lat,scale))
+    maskpoints = maskpoints + nx2.to_i.to_s + ',' + ny2.to_i.to_s
+
+    height = (y1-y2).to_i.to_s
+    width = (-x1+x2).to_i.to_s
+
+    # http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=11319
+    # http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=8764
+    # read about equalization 
+    # -equalize
+    # -contrast-stretch 0
+
+    imageMagick = "convert "
+    imageMagick += "-contrast-stretch 0 "
+    imageMagick += local_location+" "
+    imageMagick += "-crop "+maxdimension.to_i.to_s+"x"+maxdimension.to_i.to_s+"+0+0! "
+    imageMagick += "-flatten "
+    imageMagick += "-distort Perspective '"+points+"' "
+    imageMagick += "-flatten "
+    if width > height
+      imageMagick += "-crop "+width+"x"+width+"+0+0\! "
+    else
+      imageMagick += "-crop "+height+"x"+height+"+0+0\! "
+    end
+    imageMagick += "+repage "
+    imageMagick += completed_local_location
+    puts imageMagick
+    system(self.ulimit+imageMagick)
+
+    # create a mask (later we can blur edges here)
+    imageMagick2 = 'convert +antialias '
+    if width > height
+      imageMagick2 += "-size "+width+"x"+width+" "
+    else
+      imageMagick2 += "-size "+height+"x"+height+" "
+    end
+    # attempt at blurred edges in masking, but I've given up, as gdal_merge doesn't seem to respect variable-opacity alpha channels
+    imageMagick2 += ' xc:none -draw "fill black stroke red stroke-width 30 polyline '
+    imageMagick2 += maskpoints + '" '
+    imageMagick2 += ' -alpha set -channel A -transparent red -blur 0x8 -channel R -evaluate set 0 +channel '+mask_location
+    #imageMagick2 += ' xc:none -draw "fill black stroke none polyline '
+    #imageMagick2 += maskpoints + '" '
+    #imageMagick2 += ' '+mask_location
+    puts imageMagick2
+    system(self.ulimit+imageMagick2)
+
+    imageMagick3 = 'composite '+mask_location+' '+completed_local_location+' -compose DstIn -alpha Set '+masked_local_location
+    puts imageMagick3
+    system(self.ulimit+imageMagick3)
+
+    gdal_translate = "gdal_translate -of GTiff -a_srs EPSG:4326 "+coordinates+'  -co "TILED=NO" '+masked_local_location+' '+geotiff_location
+    puts gdal_translate
+    system(self.ulimit+gdal_translate)
+ 
+    #gdalwarp = 'gdalwarp -srcnodata "255" -dstnodata 0 -cblend 30 -of GTiff -t_srs EPSG:4326 '+geotiff_location+' '+warped_geotiff_location
+    gdalwarp = 'gdalwarp -of GTiff -t_srs EPSG:4326 '+geotiff_location+' '+warped_geotiff_location
+    puts gdalwarp
+    system(self.ulimit+gdalwarp)
+
+    # deletions could happen here; do it in distinct method so we can run it independently
+    delete_temp_files(path)
+
+    [x1,y1]
+  end
+
+  ########################
+  ## Run on maps:
+
+  # distort all warpables, returns upper left corner coords in x,y
+  def self.distort_warpables(scale, warpables, export, slug)
+
+    puts '> generating geotiffs of each warpable in GDAL'
+    lowest_x=0
+    lowest_y=0
+    warpable_coords = []
+    current = 0
+    warpables.each do |warpable|
+     current += 1
+
+     ## TODO: refactor to generate static status file:
+     export.status = 'warping '+current.to_s+' of '+warpables.length.to_s
+     puts 'warping '+current.to_s+' of '+warpables.length.to_s
+     export.save
+     ## 
+
+     my_warpable_coords = warpable.generate_perspectival_distort(scale,slug)
+     puts '- '+my_warpable_coords.to_s
+     warpable_coords << my_warpable_coords
+     lowest_x = my_warpable_coords.first if (my_warpable_coords.first < lowest_x || lowest_x == 0)
+     lowest_y = my_warpable_coords.last if (my_warpable_coords.last < lowest_y || lowest_y == 0)
+    end
+    [lowest_x,lowest_y,warpable_coords]
+  end
+
+  # generate a tiff from all warpable images in this set
+  def self.generate_composite_tiff(coords, origin, placed_warpables, slug, ordered)
+    directory = "public/warps/"+slug+"/"
+    composite_location = directory+slug+'-geo.tif'
+    geotiffs = ''
+    minlat = nil
+    minlon = nil
+    maxlat = nil
+    maxlon = nil
+    placed_warpables.each do |warpable|
+      warpable.nodes_array.each do |n|
+        minlat = n.lat if minlat == nil || n.lat < minlat
+        minlon = n.lon if minlon == nil || n.lon < minlon
+        maxlat = n.lat if maxlat == nil || n.lat > maxlat
+        maxlon = n.lon if maxlon == nil || n.lon > maxlon
+      end
+    end
+    first = true
+    if ordered != true
+      # sort by area; this would be overridden by a provided order
+      warpables = placed_warpables.sort{|a,b|b.poly_area <=> a.poly_area}
+    end
+    warpables.each do |warpable|
+      geotiffs += ' '+directory+warpable.id.to_s+'-geo.tif'
+      if first
+        gdalwarp = "gdalwarp -s_srs EPSG:3857 -te "+minlon.to_s+" "+minlat.to_s+" "+maxlon.to_s+" "+maxlat.to_s+" "+directory+warpable.id.to_s+'-geo.tif '+directory+slug+'-geo.tif'
+        first = false
+      else
+        gdalwarp = "gdalwarp "+directory+warpable.id.to_s+'-geo.tif '+directory+slug+'-geo.tif'
+      end
+      puts gdalwarp
+      system(self.ulimit+gdalwarp)
+    end
+    composite_location
+  end
+
+  # generates a tileset at root/public/tms/<slug>/
+  # root is something like https://mapknitter.org
+  def self.generate_tiles(key, slug, root)
+    key = "AIzaSyAOLUQngEmJv0_zcG1xkGq-CXIPpLQY8iQ" if key == "" # ugh, let's clean this up!
+    key = key || "AIzaSyAOLUQngEmJv0_zcG1xkGq-CXIPpLQY8iQ"
+    gdal2tiles = 'gdal2tiles.py -k --s_srs EPSG:3857 -t "'+slug+'" -g "'+key+'" '+root+'/public/warps/'+slug+'/'+slug+'-geo.tif '+root+'/public/tms/'+slug+"/"
+    puts gdal2tiles
+    system(self.ulimit+gdal2tiles)
+  end
+
+  # zips up tiles at root/public/tms/<slug>.zip;
+  def self.zip_tiles(slug)
+    rmzip = 'cd public/tms/ && rm '+slug+'.zip && cd ../../'
+    system(rmzip)
+    zip = 'cd public/tms/ && ' + self.ulimit + 'zip -rq '+slug+'.zip '+slug+'/ && cd ../../'
+    system(zip)
+  end
+
+  # generates a tileset at root/public/tms/<slug>/
+  def self.generate_jpg(slug, root)
+    imageMagick = 'convert -background white -flatten '+root+'/public/warps/'+slug+'/'+slug+'-geo.tif '+root+'/public/warps/'+slug+'/'+slug+'.jpg'
+    system(self.ulimit+imageMagick)
+  end
+
+  # runs the above map functions while maintaining a record of state in an Export model;
+  # we'll be replacing the export model state with a flat status file
+  def self.run_export(user,resolution,export,id,slug,root,average_scale,placed_warpables,key)
+    begin
+      export.user_id = user.id if user
+      export.status = 'starting'
+      export.tms = false
+      export.geotiff = false
+      export.zip = false
+      export.jpg = false
+      export.save
+
+      directory = "#{root}/public/warps/"+slug+"/"
+      stdin, stdout, stderr = Open3.popen3('rm -r '+directory.to_s)
+      puts stdout.readlines
+      puts stderr.readlines
+      stdin, stdout, stderr = Open3.popen3("rm -r #{root}/public/tms/#{slug}")
+      puts stdout.readlines
+      puts stderr.readlines
+
+      puts '> averaging scales; resolution: ' + resolution.to_s
+      pxperm = 100/(resolution).to_f || average_scale # pixels per meter
+      puts '> scale: ' + pxperm.to_s + 'pxperm'
+
+      puts '> distorting warpables'
+    
+      origin = self.distort_warpables(pxperm, placed_warpables, export, slug)
+      warpable_coords = origin.pop
+
+      export.status = 'compositing'
+      export.save
+
+      puts '> generating composite tiff'
+      composite_location = self.generate_composite_tiff(warpable_coords,origin,placed_warpables,slug,false) # no ordering yet
+
+      info = (`identify -quiet -format '%b,%w,%h' #{composite_location}`).split(',')
+      puts info
+
+      if info[0] != ''
+        export.geotiff = true
+        export.size = info[0]
+        export.width = info[1]
+        export.height = info[2]
+        export.cm_per_pixel = 100.0000/pxperm
+        export.status = 'tiling'
+        export.save
+      end
+
+      puts '> generating tiles'
+      export.tms = true if self.generate_tiles(key, slug, root)
+      export.status = 'zipping tiles'
+      export.save
+
+      puts '> zipping tiles'
+      export.zip = true if self.zip_tiles(slug)
+      export.status = 'creating jpg'
+      export.save
+
+      puts '> generating jpg'
+      export.jpg = true if self.generate_jpg(slug, root)
+      export.status = 'complete'
+      export.save
+
+    rescue SystemCallError
+      export.status = 'failed'
+      export.save
+    end
+    return export.status
+  end
+
+end
diff --git a/lib/gdal.rb b/lib/gdal.rb
deleted file mode 100755
index 92109f803..000000000
--- a/lib/gdal.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-require 'open3'
-
-class Gdal
-
-  def self.ulimit
-    # use ulimit to restrict to 7200 CPU seconds and 5gb virtual memory, and 5gB file storage:
-    #"ulimit -t 7200 && ulimit -v 5000000 && ulimit -f 5000000 && "
-    "ulimit -t 14400 && ulimit -v 5000000 && ulimit -f 10000000 && nice -n 19 "
-  end
- 
-  def self.raw(cmd,verbose)
-    # unused variable stdin review this function
-    stdin, stdout, stderr = Open3.popen3(self.ulimit+cmd)
-    if verbose
-      puts stderr.readlines
-      puts stdout.readlines
-    end
-  end
-
-end
diff --git a/start.sh b/start.sh
new file mode 100755
index 000000000..67cc29711
--- /dev/null
+++ b/start.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+sleep 5
+bundle exec rails s -p 3000 -b '0.0.0.0'
diff --git a/test/fixtures/demo.png b/test/fixtures/demo.png
index 3c94776ba..e5b69fbb3 100644
Binary files a/test/fixtures/demo.png and b/test/fixtures/demo.png differ
diff --git a/test/fixtures/warpables.yml b/test/fixtures/warpables.yml
index 175b2c287..37dd3eefe 100644
--- a/test/fixtures/warpables.yml
+++ b/test/fixtures/warpables.yml
@@ -14,7 +14,7 @@ one:
   nodes: "1,2,3,4"
   locked: false
   deleted: false
-  cm_per_pixel: 99.86133660017036> 
+  cm_per_pixel: 500
 
 two:
   id: 2
diff --git a/test/unit/exporter_test.rb b/test/unit/exporter_test.rb
new file mode 100644
index 000000000..d372e6688
--- /dev/null
+++ b/test/unit/exporter_test.rb
@@ -0,0 +1,57 @@
+require 'test_helper'
+
+class ExporterTest < ActiveSupport::TestCase
+  test "isolated exporter lib" do
+
+    # make a sample image
+    system('mkdir -p public/system/images/1/original')
+    system('cp test/fixtures/demo.png public/system/images/1/original/')
+    system('mkdir -p public/warps/saugus-landfill-incinerator')
+    system('mkdir -p public/tms/saugus-landfill-incinerator')
+    system('touch public/warps/saugus-landfill-incinerator/folder')
+    assert File.exist?('public/warps/saugus-landfill-incinerator/folder')
+
+    scale = 2
+
+    w = warpables(:one)    
+    coords = Exporter.generate_perspectival_distort(scale, w.map.slug, w.nodes_array, w.id, w.image_file_name, w.image, w.height, w.width)
+    assert coords
+    assert Exporter.get_working_directory(w.map.slug)
+    assert Exporter.warps_directory(w.map.slug)
+
+    map = Map.first
+
+    # get rid of existing geotiff
+    system('rm -r public/warps/saugus-landfill-incinerator/1-geo.tif')
+    # make a sample image
+    system('mkdir -p public/system/images/2/original/')
+    system('cp test/fixtures/demo.png public/system/images/2/original/test.png')
+    origin = Exporter.distort_warpables(scale, map.warpables, map.export, map.slug)
+    lowest_x, lowest_y, warpable_coords = origin
+    assert origin
+    ordered = false
+
+    system('mkdir -p public/warps/saugus-landfill-incinerator')
+    system('mkdir -p public/tms/saugus-landfill-incinerator')
+    # these params could be compressed - warpable coords is part of origin; are coords and origin required?
+    assert Exporter.generate_composite_tiff(warpable_coords, origin, map.placed_warpables, map.slug, ordered)
+    assert Exporter.generate_tiles('', map.slug, Rails.root.to_s)
+    assert Exporter.zip_tiles(map.slug)
+    assert Exporter.generate_jpg(map.slug, Rails.root.to_s)
+    resolution = 20
+    assert Exporter.run_export(User.last, resolution, map.export, map.id, map.slug, Rails.root.to_s, map.average_scale, map.placed_warpables, '')
+
+    # test deletion of the files; they were already deleted in run_export, so let's make sample ones:
+    # make a sample image
+    system('mkdir -p public/system/images/2/original/')
+    system('touch public/system/images/2/original/test.png')
+    system('mkdir -p public/warps/saugus-landfill-incinerator')
+    system('mkdir -p public/tms/saugus-landfill-incinerator')
+    system('touch public/warps/saugus-landfill-incinerator/folder')
+    assert File.exist?('public/warps/saugus-landfill-incinerator/folder')
+    system('mkdir -p public/warps/saugus-landfill-incinerator-working')
+    system('touch public/warps/saugus-landfill-incinerator/test.png')
+    assert Exporter.delete_temp_files(w.map.slug)
+  end
+end
+
diff --git a/test/unit/map_test.rb b/test/unit/map_test.rb
index b6bdfa090..8bc3d4430 100644
--- a/test/unit/map_test.rb
+++ b/test/unit/map_test.rb
@@ -42,7 +42,8 @@ class MapTest < ActiveSupport::TestCase
     assert_not_nil map.nodes
     assert_not_nil map.average_cm_per_pixel
 
-    assert_not_nil map.run_export(users(:quentin), map.average_cm_per_pixel)
+    resolution = 20
+    assert_not_nil map.run_export(users(:quentin), resolution)  #map.average_cm_per_pixel)
 
     # main issue will be that it creates and continuously updates an Export model. 
     # we could shift this to a polling model, either on the client side (eliminating the Export model)
diff --git a/test/unit/warpable_test.rb b/test/unit/warpable_test.rb
index 481f62dca..0272105bb 100644
--- a/test/unit/warpable_test.rb
+++ b/test/unit/warpable_test.rb
@@ -22,17 +22,14 @@ class WarpableTest < ActiveSupport::TestCase
   end
 
   test "try export" do
+    # make a sample image
     system('mkdir -p public/system/images/1/original')
     system('cp test/fixtures/demo.png public/system/images/1/original/')
     system('mkdir -p public/warps/saugus-landfill-incinerator')
     system('touch public/warps/saugus-landfill-incinerator/folder')
     assert File.exist?('public/warps/saugus-landfill-incinerator/folder')
-    w = warpables(:one)    
+    w = warpables(:one)
     assert_not_nil w.save_dimensions
-    assert_not_nil w.generate_perspectival_distort(10, w.map.slug)
-    assert_not_nil w.delete_temp_files(w.map.slug)
-    assert_not_nil w.working_directory(w.map.slug)
-    assert_not_nil w.warps_directory(w.map.slug)
     assert_not_nil w.user_id 
     assert File.exist?('public/warps/saugus-landfill-incinerator/1-geo.tif')
   end