diff --git a/README.md b/README.md
index 15405b77..fa534de8 100644
--- a/README.md
+++ b/README.md
@@ -58,7 +58,7 @@ networkless build.
 First, grab the sources:
 
 ```bash
-wget https://archive.apache.org/dist/commons/collections/source/commons-collections4-4.4-src.tar.gz
+wget https://archive.apache.org/dist/commons/collections/source/commons-collections4-4.5.0-M2-src.tar.gz
 ```
 
 Second, create a new `tetra` project named `commons-collections` based on those sources:
diff --git a/lib/tetra.rb b/lib/tetra.rb
index da304f70..a858a382 100644
--- a/lib/tetra.rb
+++ b/lib/tetra.rb
@@ -35,6 +35,7 @@
 require "tetra/facades/tar"
 
 # main internal classes
+require "tetra/constants"
 require "tetra/version"
 require "tetra/project_initer"
 require "tetra/project"
diff --git a/lib/tetra/constants.rb b/lib/tetra/constants.rb
new file mode 100644
index 00000000..fc022ab8
--- /dev/null
+++ b/lib/tetra/constants.rb
@@ -0,0 +1,6 @@
+# encoding: UTF-8
+
+# base module for tetra
+module Tetra
+  CCOLLECTIONS = "commons-collections4-4.5.0-M2-src".freeze
+end
diff --git a/spec/data/commons-collections4-4.4-src.tar.gz b/spec/data/commons-collections4-4.4-src.tar.gz
deleted file mode 100644
index 39108e10..00000000
Binary files a/spec/data/commons-collections4-4.4-src.tar.gz and /dev/null differ
diff --git a/spec/data/commons-collections4-4.4-src.zip b/spec/data/commons-collections4-4.4-src.zip
deleted file mode 100644
index ae7e8539..00000000
Binary files a/spec/data/commons-collections4-4.4-src.zip and /dev/null differ
diff --git a/spec/data/commons-collections4-4.5.0-M2-src.tar.gz b/spec/data/commons-collections4-4.5.0-M2-src.tar.gz
new file mode 100644
index 00000000..dba8cf29
Binary files /dev/null and b/spec/data/commons-collections4-4.5.0-M2-src.tar.gz differ
diff --git a/spec/data/commons-collections4-4.5.0-M2-src.zip b/spec/data/commons-collections4-4.5.0-M2-src.zip
new file mode 100644
index 00000000..1c0df1a1
Binary files /dev/null and b/spec/data/commons-collections4-4.5.0-M2-src.zip differ
diff --git a/spec/lib/coarse/generate_all_subcommand_spec.rb b/spec/lib/coarse/generate_all_subcommand_spec.rb
index 19bb4719..c45f0543 100644
--- a/spec/lib/coarse/generate_all_subcommand_spec.rb
+++ b/spec/lib/coarse/generate_all_subcommand_spec.rb
@@ -2,12 +2,12 @@
 
 describe "`tetra generate-all`", type: :aruba do
   it "generates specs and tarballs for a sample package, source archive workflow" do
-    archive_contents = File.read(File.join("spec", "data", "commons-collections4-4.4-src.zip"))
+    archive_contents = File.read(File.join("spec", "data", CCOLLECTIONS))
     write_file("commons-collections.zip", archive_contents)
 
     # init project
     run_simple("tetra init commons-collections commons-collections.zip")
-    cd(File.join("commons-collections", "src", "commons-collections4-4.4-src"))
+    cd(File.join("commons-collections", "src", CCOLLECTIONS))
 
     # first dry-run, all normal
     @aruba_timeout_seconds = 240
@@ -58,7 +58,7 @@
   end
 
   it "generates specs and tarballs for a sample package, manual source workflow" do
-    archive_contents = File.read(File.join("spec", "data", "commons-collections4-4.4-src.zip"))
+    archive_contents = File.read(File.join("spec", "data", "#{CCOLLECTIONS}.zip"))
     write_file("commons-collections.zip", archive_contents)
 
     # init project
@@ -79,7 +79,7 @@
     expect(output_from("tetra change-sources ../commons-collections.zip")).to include("New sources committed")
 
     # second dry-run, all normal
-    cd(File.join("src", "commons-collections4-4.4-src"))
+    cd(File.join("src", CCOLLECTIONS))
     @aruba_timeout_seconds = 240
     run_interactive("tetra dry-run")
     type("mvn package -DskipTests")
diff --git a/spec/lib/coarse/generate_spec_subcommand_spec.rb b/spec/lib/coarse/generate_spec_subcommand_spec.rb
index cd3b0884..eff3fa16 100644
--- a/spec/lib/coarse/generate_spec_subcommand_spec.rb
+++ b/spec/lib/coarse/generate_spec_subcommand_spec.rb
@@ -2,7 +2,7 @@
 
 describe "`tetra generate-spec`", type: :aruba do
   it "outputs a warning if source files are not found" do
-    archive_contents = File.read(File.join("spec", "data", "commons-collections4-4.4-src.zip"))
+    archive_contents = File.read(File.join("spec", "data", "#{CCOLLECTIONS}.zip"))
     write_file("commons-collections.zip", archive_contents)
 
     run_simple("tetra init --no-archive commons-collections")
@@ -10,7 +10,7 @@
 
     cd("src")
     run_simple("unzip ../../commons-collections.zip")
-    cd("commons-collections4-4.4-src")
+    cd(CCOLLECTIONS)
 
     run_simple("tetra change-sources --no-archive")
     expect(output_from("tetra change-sources --no-archive")).to include("New sources committed")
diff --git a/spec/lib/coarse/init_subcommand_spec.rb b/spec/lib/coarse/init_subcommand_spec.rb
index 95117efb..11ec1ddf 100644
--- a/spec/lib/coarse/init_subcommand_spec.rb
+++ b/spec/lib/coarse/init_subcommand_spec.rb
@@ -32,7 +32,7 @@
   end
 
   it "inits a new project with a zip source file" do
-    archive_contents = File.read(File.join("spec", "data", "commons-collections4-4.4-src.zip"))
+    archive_contents = File.read(File.join("spec", "data", "#{CCOLLECTIONS}.zip"))
     write_file("commons-collections.zip", archive_contents)
 
     run_simple("tetra init commons-collections commons-collections.zip")
@@ -48,8 +48,8 @@
     cd("commons-collections")
     check_directory_presence([".git", "kit", "src", "packages"], true)
 
-    check_directory_presence([File.join("src", "commons-collections4-4.4-src")], true)
-    check_file_presence([File.join("src", "commons-collections4-4.4-src", "pom.xml")], true)
+    check_directory_presence([File.join("src", CCOLLECTIONS)], true)
+    check_file_presence([File.join("src", CCOLLECTIONS, "pom.xml")], true)
 
     check_file_presence([File.join("packages", "commons-collections", "commons-collections.zip")], true)
 
@@ -58,7 +58,7 @@
   end
 
   it "inits a new project with a tar source file" do
-    archive_contents = File.read(File.join("spec", "data", "commons-collections4-4.4-src.tar.gz"))
+    archive_contents = File.read(File.join("spec", "data", "#{CCOLLECTIONS}.tar.gz"))
     write_file("commons-collections.tar.gz", archive_contents)
 
     run_simple("tetra init commons-collections commons-collections.tar.gz")
@@ -74,8 +74,8 @@
     cd("commons-collections")
     check_directory_presence([".git", "kit", "src", "packages"], true)
 
-    check_directory_presence([File.join("src", "commons-collections4-4.4-src")], true)
-    check_file_presence([File.join("src", "commons-collections4-4.4-src", "pom.xml")], true)
+    check_directory_presence([File.join("src", CCOLLECTIONS)], true)
+    check_file_presence([File.join("src", CCOLLECTIONS, "pom.xml")], true)
 
     check_file_presence([File.join("packages", "commons-collections", "commons-collections.tar.gz")], true)
 
diff --git a/spec/lib/fine/tar_spec.rb b/spec/lib/fine/tar_spec.rb
index cef9a54d..dc0f66d3 100644
--- a/spec/lib/fine/tar_spec.rb
+++ b/spec/lib/fine/tar_spec.rb
@@ -5,7 +5,7 @@
 describe Tetra::Tar do
   include Tetra::Mockers
 
-  let(:zipfile) { File.join("spec", "data", "commons-collections4-4.4-src.tar.gz") }
+  let(:zipfile) { File.join("spec", "data", "#{CCOLLECTIONS}.tar.gz") }
   let(:tar) { Tetra::Tar.new }
 
   describe "#decompress"  do
@@ -15,7 +15,7 @@
 
         files = Find.find(dir).to_a
 
-        expect(files).to include("#{dir}/commons-collections4-4.4-src/DEVELOPERS-GUIDE.html")
+        expect(files).to include("#{dir}/#{CCOLLECTIONS}/DEVELOPERS-GUIDE.html")
       end
     end
   end
diff --git a/spec/lib/fine/unzip_spec.rb b/spec/lib/fine/unzip_spec.rb
index aa0f3804..2dd565b4 100644
--- a/spec/lib/fine/unzip_spec.rb
+++ b/spec/lib/fine/unzip_spec.rb
@@ -5,7 +5,7 @@
 describe Tetra::Unzip do
   include Tetra::Mockers
 
-  let(:zipfile) { File.join("spec", "data", "commons-collections4-4.4-src.zip") }
+  let(:zipfile) { File.join("spec", "data", "#{CCOLLECTIONS}.zip") }
   let(:unzip) { Tetra::Unzip.new }
 
   describe "#decompress"  do
@@ -15,7 +15,7 @@
 
         files = Find.find(dir).to_a
 
-        expect(files).to include("#{dir}/commons-collections4-4.4-src/DEVELOPERS-GUIDE.html")
+        expect(files).to include("#{dir}/#{CCOLLECTIONS}/DEVELOPERS-GUIDE.html")
       end
     end
   end