diff --git a/scripts/bonnibel/source.py b/scripts/bonnibel/source.py
index aa09673..8fbda67 100644
--- a/scripts/bonnibel/source.py
+++ b/scripts/bonnibel/source.py
@@ -49,7 +49,7 @@ class ParseSource(Source):
     @property
     def gather(self):
         _, suffix = splitext(self.output)
-        return suffix in (".h", ".inc")
+        return suffix in (".h", ".hh", ".inc")
 
     @property
     def next(self):
@@ -113,7 +113,7 @@ def make_source(root, path):
         return CompileSource(path, root)
     elif suffix in (".cog",):
         return ParseSource(path, root)
-    elif suffix in (".h", ".inc"):
+    elif suffix in (".h", ".hh", ".inc"):
         return HeaderSource(path, root)
     else:
         raise RuntimeError(f"{path} has no Source type")
diff --git a/src/libraries/j6/j6.module b/src/libraries/j6/j6.module
index ba3c5e4..a6ff0b7 100644
--- a/src/libraries/j6/j6.module
+++ b/src/libraries/j6/j6.module
@@ -8,6 +8,7 @@ j6 = module("j6",
         "protocol_ids.cpp",
         "syscalls.s.cog",
         "sysconf.cpp.cog",
+        "thread.cpp",
     ],
     public_headers = [
         "j6/cap_flags.h.cog",
@@ -18,6 +19,7 @@ j6 = module("j6",
         "j6/protocols/service_locator.h",
         "j6/syscalls.h.cog",
         "j6/sysconf.h.cog",
+        "j6/thread.hh",
         "j6/types.h",
 
         "j6/tables/log_areas.inc",
diff --git a/src/libraries/j6/j6/thread.hh b/src/libraries/j6/j6/thread.hh
new file mode 100644
index 0000000..dd63e51
--- /dev/null
+++ b/src/libraries/j6/j6/thread.hh
@@ -0,0 +1,46 @@
+#pragma once
+/// \file thread.h
+/// High level threading interface
+
+// The kernel depends on libj6 for some shared code,
+// but should not include the user-specific code.
+#ifndef __j6kernel
+
+#include <stddef.h>
+#include <stdint.h>
+#include <j6/types.h>
+
+namespace j6 {
+
+class thread
+{
+public:
+    using proc = void (*)();
+
+    /// Constructor. Create a thread and its stack space, but
+    /// do not start executing the thread.
+    /// \arg p         The function where the thread will begin execution
+    /// \arg stack_top The address where the top of this thread's stack should be mapped
+    thread(proc p, uintptr_t stack_top);
+
+    /// Start executing the thread.
+    /// \returns  j6_status_ok if the thread was successfully started.
+    j6_status_t start();
+
+    /// Wait for the thread to stop executing.
+    void join();
+
+    thread() = delete;
+    thread(const thread&) = delete;
+
+private:
+    j6_status_t m_status;
+    j6_handle_t m_stack;
+    j6_handle_t m_thread;
+    uintptr_t m_stack_top;
+    proc m_proc;
+};
+
+} // namespace j6
+
+#endif // __j6kernel
diff --git a/src/libraries/j6/thread.cpp b/src/libraries/j6/thread.cpp
new file mode 100644
index 0000000..0fd9cc3
--- /dev/null
+++ b/src/libraries/j6/thread.cpp
@@ -0,0 +1,50 @@
+// The kernel depends on libj6 for some shared code,
+// but should not include the user-specific code.
+#ifndef __j6kernel
+
+#include <string.h>
+#include <j6/errors.h>
+#include <j6/flags.h>
+#include <j6/syscalls.h>
+#include <j6/thread.hh>
+
+extern j6_handle_t __handle_self;
+
+namespace j6 {
+
+static constexpr size_t stack_size = 0x10000;
+static constexpr size_t zeros_size = 0x10;
+
+thread::thread(thread::proc p, uintptr_t stack_top) :
+    m_stack {j6_handle_invalid},
+    m_thread {j6_handle_invalid},
+    m_stack_top {stack_top},
+    m_proc {p}
+{
+    uintptr_t stack_base = stack_top - stack_size;
+    m_status = j6_vma_create_map(&m_stack, stack_size, stack_base, j6_vm_flag_write);
+    if (m_status != j6_status_ok)
+        return;
+
+    m_stack_top -= zeros_size;
+    memset(reinterpret_cast<void*>(m_stack_top), 0, zeros_size);
+}
+
+j6_status_t
+thread::start()
+{
+    if (m_status != j6_status_ok)
+        return m_status;
+
+    if (m_thread != j6_handle_invalid)
+        return j6_err_invalid_arg;
+
+    m_status = j6_thread_create(&m_thread, __handle_self,
+        m_stack_top, reinterpret_cast<uintptr_t>(m_proc));
+
+    return m_status;
+}
+
+}
+
+#endif // __j6kernel
diff --git a/src/user/drv.uart/main.cpp b/src/user/drv.uart/main.cpp
index 70dbd4c..ae2c846 100644
--- a/src/user/drv.uart/main.cpp
+++ b/src/user/drv.uart/main.cpp
@@ -10,6 +10,7 @@
 #include <j6/protocols/service_locator.h>
 #include <j6/syscalls.h>
 #include <j6/sysconf.h>
+#include <j6/thread.hh>
 #include <j6/types.h>
 #include <util/hash.h>
 
@@ -34,7 +35,6 @@ uint8_t com2_out[out_buf_size];
 serial_port *g_com1;
 serial_port *g_com2;
 
-constexpr size_t stack_size = 0x10000;
 constexpr uintptr_t stack_top = 0xf80000000;
 
 int
@@ -119,16 +119,8 @@ main(int argc, const char **argv)
     g_com1 = &com1;
     g_com2 = &com2;
 
-    j6_handle_t child_stack_vma = j6_handle_invalid;
-    result = j6_vma_create_map(&child_stack_vma, stack_size, stack_top-stack_size, j6_vm_flag_write);
-    if (result != j6_status_ok)
-        return result;
-
-    uint64_t *sp = reinterpret_cast<uint64_t*>(stack_top - 0x10);
-    sp[0] = sp[1] = 0;
-
-    j6_handle_t child = j6_handle_invalid;
-    result = j6_thread_create(&child, __handle_self, stack_top - 0x10, reinterpret_cast<uintptr_t>(&pump_proc));
+    j6::thread pump_thread {pump_proc, stack_top};
+    result = pump_thread.start();
     if (result != j6_status_ok)
         return result;