diff --git a/tests/test_lanczos.py b/tests/test_lanczos.py
index fcfa818..b139249 100644
--- a/tests/test_lanczos.py
+++ b/tests/test_lanczos.py
@@ -8,8 +8,8 @@
 ## Add the test directory to the sys path 
 import sys
 import primate
-ind = [i for i, c in enumerate(primate.__file__) if c == '/'][-3]
-sys.path.insert(0, primate.__file__[:ind] + '/tests')
+rel_dir = primate.__file__[:(primate.__file__.find('primate') + 7)]
+sys.path.insert(0, rel_dir + '/tests')
 
 def test_basic():
   from primate.diagonalize import lanczos
diff --git a/tests/test_random.py b/tests/test_random.py
index d4234e0..7c95d23 100644
--- a/tests/test_random.py
+++ b/tests/test_random.py
@@ -6,8 +6,8 @@
 ## Add the test directory to the sys path 
 import sys
 import primate
-ind = [i for i, c in enumerate(primate.__file__) if c == '/'][-3]
-sys.path.insert(0, primate.__file__[:ind] + '/tests')
+rel_dir = primate.__file__[:(primate.__file__.find('primate') + 7)]
+sys.path.insert(0, rel_dir + '/tests')
 
 def test_seeding():
   s1 = random.rademacher(250, seed = -1)
diff --git a/tests/test_slq.py b/tests/test_slq.py
index adcbb4f..7cb543b 100644
--- a/tests/test_slq.py
+++ b/tests/test_slq.py
@@ -8,8 +8,8 @@
 ## Add the test directory to the sys path 
 import sys
 import primate
-ind = [i for i, c in enumerate(primate.__file__) if c == '/'][-3]
-sys.path.insert(0, primate.__file__[:ind] + '/tests')
+rel_dir = primate.__file__[:(primate.__file__.find('primate') + 7)]
+sys.path.insert(0, rel_dir + '/tests')
 
 def test_stochastic_quadrature():
   from primate.diagonalize import _lanczos
diff --git a/tests/test_stats.py b/tests/test_stats.py
index 564e147..6481b75 100644
--- a/tests/test_stats.py
+++ b/tests/test_stats.py
@@ -7,8 +7,8 @@
 ## Add the test directory to the sys path 
 import sys
 import primate
-ind = [i for i, c in enumerate(primate.__file__) if c == '/'][-3]
-sys.path.insert(0, primate.__file__[:ind] + '/tests')
+rel_dir = primate.__file__[:(primate.__file__.find('primate') + 7)]
+sys.path.insert(0, rel_dir + '/tests')
 
 def test_incremental_est():
   np.random.seed(1234)