diff --git a/src/common.cc b/src/common.cc
index bfb34ab..8435652 100644
--- a/src/common.cc
+++ b/src/common.cc
@@ -20,6 +20,8 @@
 #include <string>
 #include <vector>
 
+namespace {
+
 std::string vector_to_string(const std::vector<int>& vec) {
   std::stringstream ss;
   ss << "[";
@@ -34,6 +36,10 @@ std::string vector_to_string(const std::vector<int>& vec) {
   return ss.str();
 }
 
+}  // namespace
+
+namespace tesseract_decoder {
+
 std::string common::Symptom::str() const {
   std::string s = "Symptom{detectors=";
   s += vector_to_string(detectors);
@@ -241,3 +247,5 @@ stim::DetectorErrorModel common::dem_from_counts(const stim::DetectorErrorModel&
   }
   return out_dem;
 }
+
+}  // namespace tesseract_decoder
diff --git a/src/common.h b/src/common.h
index 0e048f9..ce694d8 100644
--- a/src/common.h
+++ b/src/common.h
@@ -18,6 +18,7 @@
 
 #include "stim.h"
 
+namespace tesseract_decoder {
 namespace common {
 
 // Represents the effect of an error
@@ -107,5 +108,6 @@ stim::DetectorErrorModel dem_from_counts(const stim::DetectorErrorModel& orig_de
 double merge_weights(double a, double b);
 
 }  // namespace common
+}  // namespace tesseract_decoder
 
 #endif
diff --git a/src/common.pybind.h b/src/common.pybind.h
index 693aae8..d3d5fa9 100644
--- a/src/common.pybind.h
+++ b/src/common.pybind.h
@@ -26,6 +26,8 @@
 
 namespace py = pybind11;
 
+namespace tesseract_decoder {
+
 void add_common_module(py::module& root) {
   auto m = root.def_submodule("common", "classes commonly used by the decoder");
 
@@ -217,4 +219,6 @@ void add_common_module(py::module& root) {
       )pbdoc");
 }
 
+}  // namespace tesseract_decoder
+
 #endif
diff --git a/src/common.test.cc b/src/common.test.cc
index 350853c..70eebd9 100644
--- a/src/common.test.cc
+++ b/src/common.test.cc
@@ -17,6 +17,9 @@
 #include "gtest/gtest.h"
 #include "stim.h"
 
+namespace tesseract_decoder {
+namespace {
+
 TEST(common, ErrorsStructFromDemInstruction) {
   // Test a pathological DEM error instruction
   stim::DetectorErrorModel dem("error(0.1) D0 ^  D0 D1  L0 L1 L1");
@@ -194,3 +197,6 @@ TEST(CommonTest, merge_indistinguishable_errors_two_errors) {
   auto merged_dem4 = common::merge_indistinguishable_errors(dem4, error_index_map);
   ASSERT_NEAR(get_merged_probability(merged_dem4), expected_merged_p, 1e-9);
 }
+
+}  // namespace
+}  // namespace tesseract_decoder
diff --git a/src/simplex.cc b/src/simplex.cc
index fc47b86..1540334 100644
--- a/src/simplex.cc
+++ b/src/simplex.cc
@@ -20,6 +20,8 @@
 #include "io/HMPSIO.h"
 #include "utils.h"
 
+namespace tesseract_decoder {
+
 constexpr size_t T_COORD = 2;
 
 std::string SimplexConfig::str() {
@@ -399,3 +401,5 @@ void SimplexDecoder::decode_shots(std::vector<stim::SparseShot>& shots,
 }
 
 SimplexDecoder::~SimplexDecoder() {}
+
+}  // namespace tesseract_decoder
diff --git a/src/simplex.h b/src/simplex.h
index 4288f8e..5929feb 100644
--- a/src/simplex.h
+++ b/src/simplex.h
@@ -24,6 +24,8 @@ struct HighsModel;
 struct Highs;
 enum class HighsStatus;
 
+namespace tesseract_decoder {
+
 struct SimplexConfig {
   stim::DetectorErrorModel dem;
   bool parallelize = false;
@@ -81,4 +83,6 @@ struct SimplexDecoder {
   void init_ilp();
 };
 
+}  // namespace tesseract_decoder
+
 #endif  // SIMPLEX_HPP
diff --git a/src/simplex.pybind.h b/src/simplex.pybind.h
index 27439b2..448adc6 100644
--- a/src/simplex.pybind.h
+++ b/src/simplex.pybind.h
@@ -27,7 +27,9 @@
 
 namespace py = pybind11;
 
+namespace tesseract_decoder {
 namespace {
+
 // Helper function to compile the decoder.
 std::unique_ptr<SimplexDecoder> _compile_simplex_decoder_helper(const SimplexConfig& self) {
   return std::make_unique<SimplexDecoder>(self);
@@ -41,9 +43,11 @@ SimplexConfig simplex_config_maker(py::object dem, bool parallelize = false,
       {input_dem, parallelize, window_length, window_slide_length, verbose, merge_errors});
 }
 
-};  // namespace
+}  // namespace
+}  // namespace tesseract_decoder
 
 void add_simplex_module(py::module& root) {
+  using namespace tesseract_decoder;
   auto m =
       root.def_submodule("simplex", "Module containing the SimplexDecoder and related methods");
 
diff --git a/src/simplex_main.cc b/src/simplex_main.cc
index e8da07d..ee0d484 100644
--- a/src/simplex_main.cc
+++ b/src/simplex_main.cc
@@ -23,6 +23,8 @@
 #include "stim.h"
 #include "utils.h"
 
+using namespace tesseract_decoder;
+
 struct Args {
   std::string circuit_path;
   std::string dem_path;
diff --git a/src/stim_utils.pybind.h b/src/stim_utils.pybind.h
index ff638a7..319e689 100644
--- a/src/stim_utils.pybind.h
+++ b/src/stim_utils.pybind.h
@@ -7,6 +7,8 @@
 
 #include "stim.h"
 
+namespace tesseract_decoder {
+
 namespace {
 namespace py = pybind11;
 }
@@ -23,7 +25,7 @@ T parse_py_object(py::object py_obj) {
   return T(obj_str);
 }
 
-stim::DemInstructionType parse_dit(std::string dit_str) {
+inline stim::DemInstructionType parse_dit(std::string dit_str) {
   if (dit_str == "error") return stim::DemInstructionType::DEM_ERROR;
   if (dit_str == "detector") return stim::DemInstructionType::DEM_DETECTOR;
   if (dit_str == "logical_observable") return stim::DemInstructionType::DEM_LOGICAL_OBSERVABLE;
@@ -33,12 +35,12 @@ stim::DemInstructionType parse_dit(std::string dit_str) {
   return stim::DemInstructionType::DEM_DETECTOR;
 }
 
-stim::DemTarget parse_py_dem_target(py::object py_obj) {
+inline stim::DemTarget parse_py_dem_target(py::object py_obj) {
   return stim::DemTarget::from_text(py::cast<std::string>(py_obj.attr("__str__")()));
 }
 
-stim::DemInstruction parse_py_dem_instruction(py::object py_obj, std::vector<double>& args,
-                                              std::vector<stim::DemTarget>& targets) {
+inline stim::DemInstruction parse_py_dem_instruction(py::object py_obj, std::vector<double>& args,
+                                                     std::vector<stim::DemTarget>& targets) {
   for (auto t : py_obj.attr("args_copy")()) args.push_back(t.cast<double>());
   stim::SpanRef args_ref(args);
 
@@ -66,4 +68,6 @@ void dem_setter(T& config, py::object dem) {
   config.dem = parse_py_object<stim::DetectorErrorModel>(dem);
 }
 
+}  // namespace tesseract_decoder
+
 #endif
diff --git a/src/tesseract.cc b/src/tesseract.cc
index f097617..dadfeed 100644
--- a/src/tesseract.cc
+++ b/src/tesseract.cc
@@ -53,6 +53,8 @@ struct hash<boost::dynamic_bitset<>> {
 };
 }  // namespace std
 
+namespace tesseract_decoder {
+
 std::string TesseractConfig::str() {
   auto& config = *this;
   std::stringstream ss;
@@ -567,3 +569,5 @@ void TesseractDecoder::decode_shots(std::vector<stim::SparseShot>& shots,
     obs_predicted[i] = decode(shots[i].hits);
   }
 }
+
+}  // namespace tesseract_decoder
diff --git a/src/tesseract.h b/src/tesseract.h
index 528c43b..2c406fd 100644
--- a/src/tesseract.h
+++ b/src/tesseract.h
@@ -27,6 +27,8 @@
 #include "utils.h"
 #include "visualization.h"
 
+namespace tesseract_decoder {
+
 constexpr size_t INF_DET_BEAM = std::numeric_limits<uint16_t>::max();
 constexpr int DEFAULT_DET_BEAM = 5;
 constexpr size_t DEFAULT_PQLIMIT = 200000;
@@ -123,4 +125,6 @@ struct TesseractDecoder {
                                        std::vector<DetectorCostTuple>& detector_cost_tuples) const;
 };
 
+}  // namespace tesseract_decoder
+
 #endif  // TESSERACT_DECODER_H
diff --git a/src/tesseract.perf.cc b/src/tesseract.perf.cc
index 655d357..b004d33 100644
--- a/src/tesseract.perf.cc
+++ b/src/tesseract.perf.cc
@@ -20,6 +20,8 @@
 #include "stim.h"
 #include "utils.h"
 
+using namespace tesseract_decoder;
+
 constexpr uint64_t test_data_seed = 752024;
 
 template <typename Decoder>
diff --git a/src/tesseract.pybind.cc b/src/tesseract.pybind.cc
index 9f2808f..f81486d 100644
--- a/src/tesseract.pybind.cc
+++ b/src/tesseract.pybind.cc
@@ -25,6 +25,7 @@
 #include "visualization.pybind.h"
 
 PYBIND11_MODULE(tesseract_decoder, tesseract) {
+  using namespace tesseract_decoder;
   py::module::import("stim");
 
   add_common_module(tesseract);
diff --git a/src/tesseract.pybind.h b/src/tesseract.pybind.h
index 3bdf477..384a02f 100644
--- a/src/tesseract.pybind.h
+++ b/src/tesseract.pybind.h
@@ -27,7 +27,9 @@
 
 namespace py = pybind11;
 
+namespace tesseract_decoder {
 namespace {
+
 // Helper function to compile the decoder.
 std::unique_ptr<TesseractDecoder> _compile_tesseract_decoder_helper(const TesseractConfig& self) {
   return std::make_unique<TesseractDecoder>(self);
@@ -68,12 +70,20 @@ void add_tesseract_module(py::module& root) {
   m.attr("INF_DET_BEAM") = INF_DET_BEAM;
   m.doc() = "A sentinel value indicating an infinite beam size for the decoder.";
 
-  py::class_<TesseractConfig>(m, "TesseractConfig", R"pbdoc(
+  auto py_tesseract_config = py::class_<TesseractConfig>(m, "TesseractConfig", R"pbdoc(
         Configuration object for the `TesseractDecoder`.
 
         This class holds all the parameters needed to initialize and configure a
         Tesseract decoder instance.
-    )pbdoc")
+    )pbdoc");
+  auto py_tesseract_decoder = py::class_<TesseractDecoder>(m, "TesseractDecoder", R"pbdoc(
+        A class that implements the Tesseract decoding algorithm.
+
+        It can decode syndromes from a `stim.DetectorErrorModel` to predict
+        which observables have been flipped.
+    )pbdoc");
+
+  py_tesseract_config
       .def(py::init<>(), R"pbdoc(
         Default constructor for TesseractConfig.
         Creates a new instance with default parameter values.
@@ -199,12 +209,7 @@ void add_tesseract_module(py::module& root) {
                 `TesseractConfig` object.
             )pbdoc");
 
-  py::class_<TesseractDecoder>(m, "TesseractDecoder", R"pbdoc(
-        A class that implements the Tesseract decoding algorithm.
-
-        It can decode syndromes from a `stim.DetectorErrorModel` to predict
-        which observables have been flipped.
-    )pbdoc")
+  py_tesseract_decoder
       .def(py::init<TesseractConfig>(), py::arg("config"), R"pbdoc(
         The constructor for the `TesseractDecoder` class.
 
@@ -482,4 +487,6 @@ void add_tesseract_module(py::module& root) {
                     "visualization of the algorithm");
 }
 
+}  // namespace tesseract_decoder
+
 #endif
diff --git a/src/tesseract.test.cc b/src/tesseract.test.cc
index 1ac9f00..17f1de5 100644
--- a/src/tesseract.test.cc
+++ b/src/tesseract.test.cc
@@ -23,6 +23,9 @@
 #include "stim.h"
 #include "utils.h"
 
+namespace tesseract_decoder {
+namespace {
+
 constexpr uint64_t test_data_seed = 752024;
 
 bool simplex_test_compare(stim::DetectorErrorModel& dem, std::vector<stim::SparseShot>& shots) {
@@ -395,3 +398,6 @@ TEST(tesseract, DecodeToErrorsThrowsOnInvalidSymptom) {
               err.what());
   }
 }
+
+}  // namespace
+}  // namespace tesseract_decoder
diff --git a/src/tesseract_main.cc b/src/tesseract_main.cc
index 65fb4e2..84ee9af 100644
--- a/src/tesseract_main.cc
+++ b/src/tesseract_main.cc
@@ -26,6 +26,8 @@
 #include "tesseract.h"
 #include "utils.h"
 
+using namespace tesseract_decoder;
+
 struct Args {
   std::string circuit_path;
   std::string dem_path;
diff --git a/src/tesseract_sinter_compat.pybind.h b/src/tesseract_sinter_compat.pybind.h
index c889423..6ddd728 100644
--- a/src/tesseract_sinter_compat.pybind.h
+++ b/src/tesseract_sinter_compat.pybind.h
@@ -25,6 +25,8 @@
 
 namespace py = pybind11;
 
+namespace tesseract_decoder {
+
 // These are the classes that will be exposed to Python.
 struct TesseractSinterCompiledDecoder;
 struct TesseractSinterDecoder;
@@ -398,3 +400,5 @@ void pybind_sinter_compat(py::module& root) {
   root.attr("TesseractSinterDecoder") = m.attr("TesseractSinterDecoder");
   root.attr("make_tesseract_sinter_decoders_dict") = m.attr("make_tesseract_sinter_decoders_dict");
 }
+
+}  // namespace tesseract_decoder
diff --git a/src/test_data.h b/src/test_data.h
index 137f57e..afe22bb 100644
--- a/src/test_data.h
+++ b/src/test_data.h
@@ -19,6 +19,8 @@
 
 #include "stim.h"
 
+namespace tesseract_decoder {
+
 std::vector<std::string> get_small_test_circuits() {
   return {};
 }
@@ -27,4 +29,6 @@ std::vector<std::string> get_large_test_circuits() {
   return {};
 }
 
+}  // namespace tesseract_decoder
+
 #endif  // TESSERACT_TEST_DATA_H
diff --git a/src/utils.cc b/src/utils.cc
index 56115d4..e0d2968 100644
--- a/src/utils.cc
+++ b/src/utils.cc
@@ -27,6 +27,8 @@
 #include "common.h"
 #include "stim.h"
 
+namespace tesseract_decoder {
+
 std::vector<std::vector<double>> get_detector_coords(const stim::DetectorErrorModel& dem) {
   std::vector<std::vector<double>> detector_coords;
   for (const stim::DemInstruction& instruction : dem.flattened().instructions) {
@@ -279,3 +281,5 @@ uint64_t vector_to_u64_mask(const std::vector<int>& v) {
   }
   return mask;
 }
+
+}  // namespace tesseract_decoder
diff --git a/src/utils.h b/src/utils.h
index 73d7817..d2e9013 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -26,6 +26,8 @@
 #include "common.h"
 #include "stim.h"
 
+namespace tesseract_decoder {
+
 constexpr const double EPSILON = 1e-7;
 
 std::vector<std::vector<double>> get_detector_coords(const stim::DetectorErrorModel& dem);
@@ -54,4 +56,7 @@ std::vector<common::Error> get_errors_from_dem(const stim::DetectorErrorModel& d
 std::vector<std::string> get_files_recursive(const std::string& directory_path);
 
 uint64_t vector_to_u64_mask(const std::vector<int>& v);
+
+}  // namespace tesseract_decoder
+
 #endif  // __TESSERACT_UTILS_H__
diff --git a/src/utils.pybind.h b/src/utils.pybind.h
index 92ba668..71b3af7 100644
--- a/src/utils.pybind.h
+++ b/src/utils.pybind.h
@@ -24,6 +24,7 @@
 namespace py = pybind11;
 
 void add_utils_module(py::module& root) {
+  using namespace tesseract_decoder;
   auto m = root.def_submodule("utils", "utility methods");
 
   m.attr("EPSILON") = EPSILON;
diff --git a/src/visualization.cc b/src/visualization.cc
index ecd78fa..c9c6f9b 100644
--- a/src/visualization.cc
+++ b/src/visualization.cc
@@ -1,6 +1,8 @@
 
 #include "visualization.h"
 
+namespace tesseract_decoder {
+
 void Visualizer::add_errors(const std::vector<common::Error>& errors) {
   for (auto& error : errors) {
     lines.push_back(error.str());
@@ -55,3 +57,5 @@ void Visualizer::write(const char* fpath) {
 
   fclose(fout);
 }
+
+}  // namespace tesseract_decoder
diff --git a/src/visualization.h b/src/visualization.h
index 64d9ad5..d3af2e9 100644
--- a/src/visualization.h
+++ b/src/visualization.h
@@ -7,6 +7,8 @@
 
 #include "common.h"
 
+namespace tesseract_decoder {
+
 struct Visualizer {
   void add_detector_coords(const std::vector<std::vector<double>>&);
   void add_errors(const std::vector<common::Error>&);
@@ -19,4 +21,6 @@ struct Visualizer {
   std::list<std::string> lines;
 };
 
+}  // namespace tesseract_decoder
+
 #endif
diff --git a/src/visualization.pybind.h b/src/visualization.pybind.h
index 820bf86..330f08e 100644
--- a/src/visualization.pybind.h
+++ b/src/visualization.pybind.h
@@ -10,7 +10,7 @@ namespace py = pybind11;
 
 void add_visualization_module(py::module& root) {
   auto m = root.def_submodule("viz", "Module containing the visualization tools");
-  py::class_<Visualizer>(m, "Visualizer")
+  py::class_<tesseract_decoder::Visualizer>(m, "Visualizer")
       .def(py::init<>())
-      .def("write", &Visualizer::write, py::arg("fpath"));
+      .def("write", &tesseract_decoder::Visualizer::write, py::arg("fpath"));
 }