diff --git a/lib/skyfall/car_archive.rb b/lib/skyfall/car_archive.rb
deleted file mode 100644
index 47c7491..0000000
--- a/lib/skyfall/car_archive.rb
+++ /dev/null
@@ -1,158 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'cid'
-require_relative 'errors'
-require_relative 'extensions'
-
-require 'base64'
-require 'cbor'
-require 'stringio'
-
-# CAR v1: https://ipld.io/specs/transport/car/carv1/
-# multicodec codes: https://github.com/multiformats/multicodec/blob/master/table.csv
-
-module Skyfall
-  class CarSection
-    attr_reader :cid
-
-    def initialize(cid, body_data)
-      @cid = cid
-      @body_data = body_data
-    end
-
-    def body
-      @body ||= CarArchive.convert_data(CBOR.decode(@body_data))
-    end
-  end
-
-  class CarArchive
-    using Skyfall::Extensions
-
-    attr_reader :roots, :sections
-
-    def initialize(data)
-      @sections = []
-      @buffer = StringIO.new(data)
-
-      read_header(@buffer)
-    end
-
-    def section_with_cid(cid)
-      if section = @sections.detect { |s| s.cid == cid }
-        return section.body
-      end
-
-      if @buffer
-        while !@buffer.eof?
-          section = read_section(@buffer)
-          return section.body if section.cid == cid
-        end
-      end
-
-      @buffer = nil
-      nil
-    end
-
-    def sections
-      if @buffer
-        read_section(@buffer) while !@buffer.eof?
-        @buffer = nil
-      end
-
-      @sections
-    end
-
-    def self.convert_data(object)
-      if object.is_a?(Hash)
-        object.each do |k, v|
-          if v.is_a?(Hash) || v.is_a?(Array)
-            convert_data(v)
-          elsif v.is_a?(CBOR::Tagged)
-            object[k] = make_cid_link(v)
-          elsif v.is_a?(String) && v.encoding == Encoding::ASCII_8BIT
-            object[k] = make_bytes(v)
-          end
-        end
-      elsif object.is_a?(Array)
-        object.each_with_index do |v, i|
-          if v.is_a?(Hash) || v.is_a?(Array)
-            convert_data(v)
-          elsif v.is_a?(CBOR::Tagged)
-            object[i] = make_cid_link(v)
-          elsif v.is_a?(String) && v.encoding == Encoding::ASCII_8BIT
-            object[i] = make_bytes(v)
-          end
-        end
-      else
-        raise DecodeError, "Unexpected value type in record: #{object}"
-      end
-    end
-
-    def self.make_cid_link(cid)
-      { '$link' => CID.from_cbor_tag(cid) }
-    end
-
-    def self.make_bytes(data)
-      { '$bytes' => Base64.encode64(data).chomp.gsub(/=+$/, '') }
-    end
-
-    def inspect
-      vars = instance_variables.map { |v|
-        if v == :@sections && @buffer
-          "#{v}=[...]"
-        else
-          "#{v}=#{instance_variable_get(v).inspect}"
-        end
-      }
-
-      "#<#{self.class}:0x#{object_id} #{vars.join(", ")}>"
-    end
-
-    private
-
-    def read_header(buffer)
-      len = buffer.read_varint
-
-      header_data = buffer.read(len)
-      raise DecodeError.new("Header too short: #{header_data}") unless header_data.length == len
-
-      header = CBOR.decode(header_data)
-      raise UnsupportedError.new("Unexpected CAR version: #{header['version']}") unless header['version'] == 1
-      @roots = header['roots'].map { |x| CID.from_cbor_tag(x) }
-    end
-
-    def read_section(buffer)
-      len = buffer.read_varint
-
-      section_data = buffer.read(len)
-      raise DecodeError.new("Section too short: #{section_data}") unless section_data.length == len
-
-      sbuffer = StringIO.new(section_data)
-
-      version = sbuffer.read_varint
-      raise UnsupportedError.new("Unexpected CID version: #{version}") unless version == 1
-
-      codec = sbuffer.read_varint
-      raise UnsupportedError.new("Unexpected CID codec: #{codec}") unless codec == 0x71  # dag-cbor
-
-      hash = sbuffer.read_varint
-      raise UnsupportedError.new("Unexpected CID hash: #{hash}") unless hash == 0x12  # sha2-256
-
-      clen = sbuffer.read_varint
-      raise UnsupportedError.new("Unexpected CID length: #{clen}") unless clen == 32
-
-      prefix = section_data[0...sbuffer.pos]
-
-      cid_data = sbuffer.read(clen)
-      raise DecodeError.new("CID too short: #{cid_data}") unless cid_data.length == clen
-
-      cid = CID.new(prefix + cid_data)
-
-      body_data = sbuffer.read
-      new_section = CarSection.new(cid, body_data)
-
-      @sections << new_section
-      new_section
-    end
-  end
-end
diff --git a/lib/skyfall/cid.rb b/lib/skyfall/cid.rb
deleted file mode 100644
index ae62ca8..0000000
--- a/lib/skyfall/cid.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-# frozen_string_literal: true
-
-require_relative 'errors'
-
-require 'base32'
-
-# CIDs in DAG-CBOR: https://ipld.io/specs/codecs/dag-cbor/spec/
-# CIDs in JSON: https://ipld.io/specs/codecs/dag-json/spec/
-# multibase: https://github.com/multiformats/multibase
-
-module Skyfall
-  class CID
-    attr_reader :data
-
-    def self.from_cbor_tag(tag)
-      data = tag.value
-      raise DecodeError.new("Unexpected first byte of CID: #{data[0]}") unless data[0] == "\x00"
-      CID.new(data[1..-1])
-    end
-
-    def self.from_json(string)
-      raise DecodeError.new("Unexpected CID length") unless string.length == 59
-      raise DecodeError.new("Unexpected CID prefix") unless string[0] == 'b'
-
-      data = Base32.decode(string[1..-1].upcase)
-      CID.new(data)
-    end
-
-    def initialize(data)
-      @data = data
-    end
-
-    def to_s
-      'b' + Base32.encode(@data).downcase.gsub(/=+$/, '')
-    end
-
-    def inspect
-      "CID(\"#{to_s}\")"
-    end
-
-    def ==(other)
-      other.is_a?(CID) && @data == other.data
-    end
-  end
-end
diff --git a/lib/skyfall/extensions.rb b/lib/skyfall/extensions.rb
deleted file mode 100644
index 6b89e4d..0000000
--- a/lib/skyfall/extensions.rb
+++ /dev/null
@@ -1,36 +0,0 @@
-# frozen_string_literal: true
-
-require 'cbor'
-require 'stringio'
-
-module Skyfall
-
-  # @private
-  module Extensions
-
-    refine StringIO do
-      # https://en.wikipedia.org/wiki/LEB128
-      def read_varint
-        shift = 1
-        value = 0
-
-        loop do
-          byte = self.readbyte
-          value += byte % 128 * shift
-          break if byte < 128
-          shift *= 128
-        end
-
-        value
-      end
-    end
-
-    refine CBOR.singleton_class do
-      def decode_sequence(data)
-        unpacker = CBOR::Unpacker.new(StringIO.new(data))
-        unpacker.each.to_a
-      end
-    end
-
-  end
-end
diff --git a/lib/skyfall/firehose/commit_message.rb b/lib/skyfall/firehose/commit_message.rb
index faf21a6..5552222 100644
--- a/lib/skyfall/firehose/commit_message.rb
+++ b/lib/skyfall/firehose/commit_message.rb
@@ -1,10 +1,9 @@
 # frozen_string_literal: true
 
-require_relative '../car_archive'
-require_relative '../cid'
 require_relative '../firehose'
 require_relative 'message'
 require_relative 'operation'
+require 'oxygene'
 
 module Skyfall
 
@@ -39,19 +38,19 @@ module Skyfall
       @data_object['since']
     end
 
-    # @return [CID, nil] CID (Content Identifier) of data of the previous commit in the repo
+    # @return [Oxygene::CID, nil] CID (Content Identifier) of data of the previous commit in the repo
     def prev_data
-      @prev_data ||= CID.from_cbor_tag(@data_object['prevData'])
+      @prev_data ||= Oxygene::CID.from_cbor_tag(@data_object['prevData'])
     end
 
-    # @return [CID] CID (Content Identifier) of the commit
+    # @return [Oxygene::CID] CID (Content Identifier) of the commit
     def commit
-      @commit ||= CID.from_cbor_tag(@data_object['commit'])
+      @commit ||= Oxygene::CID.from_cbor_tag(@data_object['commit'])
     end
 
-    # @return [Skyfall::CarArchive] commit data in the form of a parsed CAR archive
+    # @return [Oxygene::CARArchive] commit data in the form of a parsed CAR archive
     def blocks
-      @blocks ||= CarArchive.new(@data_object['blocks'])
+      @blocks ||= Oxygene::CARArchive.new(@data_object['blocks'])
     end
 
     # @return [Array<Firehose::Operation>] record operations (usually one) included in the commit
diff --git a/lib/skyfall/firehose/message.rb b/lib/skyfall/firehose/message.rb
index d2e8244..1882cdd 100644
--- a/lib/skyfall/firehose/message.rb
+++ b/lib/skyfall/firehose/message.rb
@@ -1,10 +1,10 @@
 # frozen_string_literal: true
 
 require_relative '../errors'
-require_relative '../extensions'
 require_relative '../firehose'
 
 require 'cbor'
+require 'oxygene'
 require 'time'
 
 module Skyfall
@@ -24,7 +24,7 @@ module Skyfall
   # the {Skyfall::Stream#on_raw_message} event handler.
 
   class Firehose::Message
-    using Skyfall::Extensions
+    using Oxygene::Extensions
 
     # Type of the message (e.g. `:commit`, `:identity` etc.)
     # @return [Symbol]
diff --git a/lib/skyfall/firehose/operation.rb b/lib/skyfall/firehose/operation.rb
index 5d0452f..768c788 100644
--- a/lib/skyfall/firehose/operation.rb
+++ b/lib/skyfall/firehose/operation.rb
@@ -2,6 +2,7 @@
 
 require_relative '../collection'
 require_relative '../firehose'
+require 'oxygene'
 
 module Skyfall
 
@@ -73,9 +74,9 @@ module Skyfall
       "at://#{repo}/#{@json['path']}"
     end
 
-    # @return [CID, nil] CID (Content Identifier) of the record (nil for delete operations)
+    # @return [Oxygene::CID, nil] CID (Content Identifier) of the record (nil for delete operations)
     def cid
-      @cid ||= @json['cid'] && CID.from_cbor_tag(@json['cid'])
+      @cid ||= @json['cid'] && Oxygene::CID.from_cbor_tag(@json['cid'])
     end
 
     # @return [Hash, nil] record data as a plain Ruby Hash (nil for delete operations)
diff --git a/lib/skyfall/firehose/sync_message.rb b/lib/skyfall/firehose/sync_message.rb
index 6ba2b92..1d0147d 100644
--- a/lib/skyfall/firehose/sync_message.rb
+++ b/lib/skyfall/firehose/sync_message.rb
@@ -1,8 +1,8 @@
 # frozen_string_literal: true
 
-require_relative '../car_archive'
 require_relative '../firehose'
 require_relative 'message'
+require 'oxygene'
 
 module Skyfall
 
@@ -32,9 +32,9 @@ module Skyfall
       @rev ||= @data_object['rev']
     end
 
-    # @return [Skyfall::CarArchive] commit data in the form of a parsed CAR archive
+    # @return [Oxygene::CARArchive] commit data in the form of a parsed CAR archive
     def blocks
-      @blocks ||= CarArchive.new(@data_object['blocks'])
+      @blocks ||= Oxygene::CARArchive.new(@data_object['blocks'])
     end
   end
 end
diff --git a/lib/skyfall/jetstream/operation.rb b/lib/skyfall/jetstream/operation.rb
index 8c0caea..5ef91c2 100644
--- a/lib/skyfall/jetstream/operation.rb
+++ b/lib/skyfall/jetstream/operation.rb
@@ -2,6 +2,7 @@
 
 require_relative '../collection'
 require_relative '../jetstream'
+require 'oxygene'
 
 module Skyfall
 
@@ -73,9 +74,9 @@ module Skyfall
       "at://#{repo}/#{collection}/#{rkey}"
     end
 
-    # @return [CID, nil] CID (Content Identifier) of the record (nil for delete operations)
+    # @return [Oxygene::CID, nil] CID (Content Identifier) of the record (nil for delete operations)
     def cid
-      @cid ||= @json['cid'] && CID.from_json(@json['cid'])
+      @cid ||= @json['cid'] && Oxygene::CID.from_json(@json['cid'])
     end
 
     # @return [Hash, nil] record data as a plain Ruby Hash (nil for delete operations)
diff --git a/lib/skyfall/label.rb b/lib/skyfall/label.rb
index ac2dbb8..b09944e 100644
--- a/lib/skyfall/label.rb
+++ b/lib/skyfall/label.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative 'errors'
+require 'oxygene'
 require 'time'
 
 module Skyfall
@@ -60,9 +61,9 @@ module Skyfall
       @data['uri']
     end
 
-    # @return [CID, nil] CID of the specific version of the subject that this label applies to
+    # @return [Oxygene::CID, nil] CID of the specific version of the subject that this label applies to
     def cid
-      @cid ||= @data['cid'] && CID.from_json(@data['cid'])
+      @cid ||= @data['cid'] && Oxygene::CID.from_json(@data['cid'])
     end
 
     # @return [String] label value
diff --git a/skyfall.gemspec b/skyfall.gemspec
index 7042460..8b0f584 100644
--- a/skyfall.gemspec
+++ b/skyfall.gemspec
@@ -34,9 +34,7 @@ Gem::Specification.new do |spec|
 
   spec.require_paths = ["lib"]
 
-  spec.add_dependency 'base32', '~> 0.3', '>= 0.3.4'
-  spec.add_dependency 'base64', '~> 0.1'
-  spec.add_dependency 'cbor', '~> 0.5', '>= 0.5.9.6'
   spec.add_dependency 'eventmachine', '~> 1.2', '>= 1.2.7'
   spec.add_dependency 'faye-websocket', '~> 0.12'
+  spec.add_dependency 'oxygene', '>= 0.0.1'
 end