diff --git a/Gemfile b/Gemfile
index 93dc9a6..98429ba 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,6 +14,7 @@ end
 
 group :test do
   gem 'factory_bot', '~> 6.2'
+  gem 'rack-test', '~> 2.1'
   gem 'rspec', '~> 3.12'
   gem 'rspec-github', '~> 2.4'
   gem 'simplecov', '~> 0.22'
diff --git a/Gemfile.lock b/Gemfile.lock
index 84170bd..9a59457 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -76,6 +76,8 @@ GEM
     rack (3.0.10)
     rack-accept (0.4.5)
       rack (>= 0.4)
+    rack-test (2.1.0)
+      rack (>= 1.3)
     rackup (2.1.0)
       rack (>= 3)
       webrick (~> 1.8)
@@ -146,6 +148,7 @@ PLATFORMS
 DEPENDENCIES
   cmr-entity-resolution!
   factory_bot (~> 6.2)
+  rack-test (~> 2.1)
   rake (~> 13.0)
   rspec (~> 3.12)
   rspec-github (~> 2.4)
diff --git a/spec/unit/api_spec.rb b/spec/unit/api_spec.rb
new file mode 100644
index 0000000..d76326b
--- /dev/null
+++ b/spec/unit/api_spec.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+require 'rack/test'
+
+require_relative '../../lib/api'
+
+describe API do
+  include Rack::Test::Methods
+
+  def app
+    API
+  end
+
+  describe 'GET /health' do
+    it 'returns 200' do
+      get '/health'
+      expect(last_response.status).to eq(200)
+    end
+
+    it 'includes a status message' do
+      get '/health'
+      expect(last_response.body).to eq({ status: 'ok' }.to_json)
+    end
+  end
+
+  # TODO: Write tests for a valid source.
+  describe 'POST /import' do
+    context 'with an invalid source' do
+      it 'returns 404' do
+        post '/import', { source: 'invalid' }
+        expect(last_response.status).to eq(404)
+      end
+
+      it 'includes a message' do
+        post '/import', { source: 'invalid' }
+        expect(last_response.body).to \
+          eq({ status: 'error', message: 'Source "invalid" not found.' }.to_json)
+      end
+    end
+  end
+end
diff --git a/spec/unit/source/api/base_spec.rb b/spec/unit/source/api/base_spec.rb
new file mode 100644
index 0000000..783a020
--- /dev/null
+++ b/spec/unit/source/api/base_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require_relative '../../../../lib/source/api/base'
+
+describe Source::API::Base do
+  subject(:source) { described_class.new(config) }
+
+  let(:config) { { type: 'API::Base', payload: } }
+  let(:payload) { [{ id: 'rspec-0' }, { id: 'rspec-1' }] }
+
+  describe '#each' do
+    context 'when the payload is an array' do
+      it 'yields each record' do
+        expect { |b| source.each(&b) }.to yield_successive_args(*payload)
+      end
+    end
+
+    context 'when the payload is not an array' do
+      let(:payload) { { id: 'rspec-3' } }
+
+      it 'yields for the single record' do
+        expect { |b| source.each(&b) }.to yield_with_args(payload)
+      end
+    end
+  end
+
+  describe '#name' do
+    context 'when no name was specified' do
+      it 'uses the class name' do
+        expect(source.name).to eq('API::Base')
+      end
+    end
+
+    context 'when a name was specified' do
+      let(:config) { { name: 'specified' } }
+
+      it 'uses the specified name' do
+        expect(source.name).to eq('specified')
+      end
+    end
+  end
+end
diff --git a/spec/unit/source/base_spec.rb b/spec/unit/source/base_spec.rb
new file mode 100644
index 0000000..fe4a58d
--- /dev/null
+++ b/spec/unit/source/base_spec.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require_relative '../../../lib/source/base'
+
+describe Source::Base do
+  subject(:source) { described_class.new(config) }
+
+  let(:config) { {} }
+
+  describe '#each' do
+    it 'raises an exception' do
+      expect { source.each }.to raise_error(NotImplementedError)
+    end
+  end
+
+  describe '#name' do
+    context 'when no name was specified' do
+      it 'uses the class name' do
+        expect(source.name).to eq('Base')
+      end
+    end
+
+    context 'when a name was specified' do
+      let(:config) { { name: 'specified' } }
+
+      it 'uses the specified name' do
+        expect(source.name).to eq('specified')
+      end
+    end
+  end
+end