diff --git a/.travis.yml b/.travis.yml
index d1083ce25..5d0f44be7 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,4 +10,33 @@ before_install:
 install:
   - pip install -r infra/travis/requirements.txt
 
+matrix:
+  include:
+    - name: "libfuzzer address x86_64"
+      env:
+        - TRAVIS_ENGINE=libfuzzer
+        - TRAVIS_SANITIZER=address
+        - TRAVIS_ARCHITECTURE=x86_64
+    - name: "libfuzzer memory x86_64"
+      env:
+        - TRAVIS_ENGINE=libfuzzer
+        - TRAVIS_SANITIZER=memory
+        - TRAVIS_ARCHITECTURE=x86_64
+    - name: "libfuzzer undefined x86_64"
+      env:
+        - TRAVIS_SANITIZER=undefined
+        - TRAVIS_ENGINE=libfuzzer
+        - TRAVIS_ARCHITECTURE=x86_64
+    - name: "afl address x86_64"
+      env:
+        - TRAVIS_ENGINE=afl
+        - TRAVIS_SANITIZER=address
+        - TRAVIS_ARCHITECTURE=x86_64
+    - name: "none address x86_64"
+      env:
+        - TRAVIS_ENGINE=none
+        - TRAVIS_SANITIZER=address
+        - TRAVIS_ARCHITECTURE=x86_64
+      # TODO(metzman) Add a libfuzzer address i386 job.
+
 script: ./infra/travis/travis_build.py
diff --git a/infra/travis/travis_build.py b/infra/travis/travis_build.py
index eb190ea6e..32b2358fd 100755
--- a/infra/travis/travis_build.py
+++ b/infra/travis/travis_build.py
@@ -23,7 +23,8 @@ import re
 import subprocess
 import yaml
 
-DEFAULT_FUZZING_ENGINES = ['afl', 'libfuzzer']
+DEFAULT_ARCHITECTURES = ['x86_64']
+DEFAULT_ENGINES = ['afl', 'libfuzzer']
 DEFAULT_SANITIZERS = ['address', 'undefined']
 
 
@@ -53,57 +54,62 @@ def execute_helper_command(helper_command):
   subprocess.check_call(command)
 
 
-def build_fuzzers(project, sanitizer, engine, architecture='x86_64'):
+def build_fuzzers(project, engine, sanitizer, architecture):
   """Execute helper.py's build_fuzzers command on |project|. Build the fuzzers
-  with |sanitizer| and |engine|."""
+  with |engine| and |sanitizer| for |architecture|."""
   execute_helper_command([
       'build_fuzzers', project, '--engine', engine, '--sanitizer', sanitizer,
       '--architecture', architecture
   ])
 
 
-def check_build(project, sanitizer, engine, architecture='x86_64'):
+def check_build(project, engine, sanitizer, architecture):
   """Execute helper.py's check_build command on |project|, assuming it was most
-  recently built with |sanitizer| and |engine|."""
+  recently built with |engine| and |sanitizer| for |architecture|."""
   execute_helper_command([
       'check_build', project, '--engine', engine, '--sanitizer', sanitizer,
       '--architecture', architecture
   ])
 
 
+def should_build(project_yaml):
+  """Is the build specified by travis enabled in the |project_yaml|?"""
+  def is_enabled(env_var, yaml_name, defaults):
+    """Is the value of |env_var| enabled in |project_yaml| (in the |yaml_name|
+    section)? Uses |defaults| if |yaml_name| section is unspecified."""
+    return os.getenv(env_var) in project_yaml.get(yaml_name, defaults)
+
+  return (is_enabled('TRAVIS_ENGINE', 'fuzzing_engines', DEFAULT_ENGINES) and
+          is_enabled('TRAVIS_SANITIZER', 'sanitizers', DEFAULT_SANITIZERS) and
+          is_enabled(
+              'TRAVIS_ARCHITECTURE', 'architectures', DEFAULT_ARCHITECTURES))
+
 def build_project(project):
-  """Do all build of |project|."""
-  print('Building project', project)
+  """Do the build of |project| that is specified by the TRAVIS_* environment
+  variables (TRAVIS_SANITIZER, TRAVIS_ENGINE, and TRAVIS_ARCHITECTURE)."""
   root = get_oss_fuzz_root()
   project_yaml_path = os.path.join(root, 'projects', project, 'project.yaml')
   with open(project_yaml_path) as fp:
     project_yaml = yaml.safe_load(fp)
 
   if project_yaml.get('disabled', False):
+    print('Project {0} is disabled, not building.'.format(project))
     return
 
-  fuzzing_engines = project_yaml.get('fuzzing_engines', DEFAULT_FUZZING_ENGINES)
-  if 'none' in fuzzing_engines:
-    # no engine builds always use ASAN.
-    build_fuzzers(project, 'address', 'none')
+  engine = os.getenv('TRAVIS_ENGINE')
+  sanitizer = os.getenv('TRAVIS_SANITIZER')
+  architecture = os.getenv('TRAVIS_ARCHITECTURE')
+
+  if not should_build(project_yaml):
+    print(('Specified build: engine: {0}, sanitizer: {1}, architecture: {2} '
+           'not enabled for this project: {3}. Not building.').format(
+               engine, sanitizer, architecture, project))
+
     return
 
-  if 'afl' in fuzzing_engines:
-    # AFL builds always use ASAN.
-    build_fuzzers(project, 'address', 'afl')
-    check_build(project, 'address', 'afl')
-
-  if 'libfuzzer' not in fuzzing_engines:
-    return
-
-  for sanitizer in project_yaml.get('sanitizers', DEFAULT_SANITIZERS):
-    build_fuzzers(project, sanitizer, 'libfuzzer')
-    check_build(project, sanitizer, 'libfuzzer')
-
-  if 'i386' in project_yaml.get('architectures', []):
-    # i386 builds always use libFuzzer and ASAN.
-    build_fuzzers(project, 'address', 'libfuzzer', 'i386')
-    check_build(project, 'address', 'libfuzzer', 'i386')
+  print('Building project', project)
+  build_fuzzers(project, engine, sanitizer, architecture)
+  check_build(project, engine, sanitizer, architecture)
 
 
 def main():