diff --git a/Makefile b/Makefile
index d900bb21a9..a20c48fa17 100644
--- a/Makefile
+++ b/Makefile
@@ -14,6 +14,8 @@ else
         AR = gcc-ar
       endif
     endif
+
+    ALPINE=$(wildcard /etc/alpine-release)
   endif
 
   ifeq ($(UNAME_S),Darwin)
@@ -396,9 +398,14 @@ endif
 
 # target specific build options
 libponyrt.buildoptions = -DPONY_NO_ASSERT
+libponyrt-pic.buildoptions = -DPONY_NO_ASSERT
 
 libponyrt.tests.linkoptions += -rdynamic
 
+ifneq ($(ALPINE),)
+  libponyrt.tests.linkoptions += -lexecinfo
+endif
+
 libponyc.buildoptions = -D__STDC_CONSTANT_MACROS
 libponyc.buildoptions += -D__STDC_FORMAT_MACROS
 libponyc.buildoptions += -D__STDC_LIMIT_MACROS
@@ -410,16 +417,29 @@ libponyc.tests.buildoptions += -DPONY_PACKAGES_DIR=\"$(packages_abs_src)\"
 
 libponyc.tests.linkoptions += -rdynamic
 
+ifneq ($(ALPINE),)
+  libponyc.tests.linkoptions += -lexecinfo
+endif
+
 libponyc.benchmarks.buildoptions = -D__STDC_CONSTANT_MACROS
 libponyc.benchmarks.buildoptions += -D__STDC_FORMAT_MACROS
 libponyc.benchmarks.buildoptions += -D__STDC_LIMIT_MACROS
 
 libgbenchmark.buildoptions := -DHAVE_POSIX_REGEX
 
+ifneq ($(ALPINE),)
+  libponyc.benchmarks.linkoptions += -lexecinfo
+  libponyrt.benchmarks.linkoptions += -lexecinfo
+endif
+
 ponyc.buildoptions = $(libponyc.buildoptions)
 
 ponyc.linkoptions += -rdynamic
 
+ifneq ($(ALPINE),)
+  ponyc.linkoptions += -lexecinfo
+endif
+
 ifeq ($(OSTYPE), linux)
   libponyrt-pic.buildoptions += -fpic
 endif
diff --git a/src/common/platform.h b/src/common/platform.h
index 164945960c..0a2d9d76f7 100644
--- a/src/common/platform.h
+++ b/src/common/platform.h
@@ -1,6 +1,12 @@
 #ifndef PLATFORM_H
 #define PLATFORM_H
 
+#ifdef __linux__
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#endif
+
 #include <stdbool.h>
 #include <stdint.h>
 
diff --git a/src/common/pony/detail/atomics.h b/src/common/pony/detail/atomics.h
index 764db96c81..149f6a9e5e 100644
--- a/src/common/pony/detail/atomics.h
+++ b/src/common/pony/detail/atomics.h
@@ -36,7 +36,7 @@ using std::atomic_thread_fence;
 #  endif
 #elif defined(__GNUC__) && !defined(__clang__)
 #  include <features.h>
-#  if __GNUC_PREREQ(4, 9)
+#  if ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((4) << 16) + (9))
 #    ifdef __cplusplus
 //     g++ doesn't like C11 atomics. We never need atomic ops in C++ files so
 //     we only define the atomic types.
@@ -50,7 +50,7 @@ using std::atomic_thread_fence;
 #      define PONY_ATOMIC(T) T _Atomic
 #      define PONY_ATOMIC_RVALUE(T) T _Atomic
 #    endif
-#  elif __GNUC_PREREQ(4, 7)
+#  elif ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((4) << 16) + (7))
 #    define PONY_ATOMIC(T) alignas(sizeof(T)) T
 #    define PONY_ATOMIC_RVALUE(T) T
 #    define PONY_ATOMIC_BUILTINS
diff --git a/src/common/ponyassert.h b/src/common/ponyassert.h
index 80a0d8ec2b..f8fcb324ec 100644
--- a/src/common/ponyassert.h
+++ b/src/common/ponyassert.h
@@ -2,11 +2,12 @@
 #define PLATFORM_PONYASSERT_H
 
 #include "platform.h"
+#include <assert.h>
 
 PONY_EXTERN_C_BEGIN
 
-#if defined(NDEBUG) && defined(PONY_NO_ASSERT)
-#  define pony_assert(expr) ((void)0)
+#if defined(PONY_NO_ASSERT)
+#  define pony_assert(expr) assert(expr)
 #else
 #  define pony_assert(expr) \
     ((expr) ? (void)0 : \
diff --git a/src/libponyc/codegen/genexe.c b/src/libponyc/codegen/genexe.c
index d82d6fcde9..0028b6ad9f 100644
--- a/src/libponyc/codegen/genexe.c
+++ b/src/libponyc/codegen/genexe.c
@@ -261,6 +261,7 @@ static bool link_exe(compile_t* c, ast_t* program,
       "Warning: environment variable $CC undefined, using %s as the linker\n",
       PONY_COMPILER);
   }
+
   const char* mcx16_arg = target_is_ilp32(c->opt->triple) ? "" : "-mcx16";
   const char* fuseld = target_is_linux(c->opt->triple) ? "-fuse-ld=gold" : "";
   const char* ldl = target_is_linux(c->opt->triple) ? "-ldl" : "";
diff --git a/src/libponyrt/asio/asio.c b/src/libponyrt/asio/asio.c
index 36fb19cd48..79f29ca8c6 100644
--- a/src/libponyrt/asio/asio.c
+++ b/src/libponyrt/asio/asio.c
@@ -33,6 +33,11 @@ asio_backend_t* ponyint_asio_get_backend()
   return running_base.backend;
 }
 
+uint32_t ponyint_asio_get_cpu()
+{
+  return asio_cpu;
+}
+
 void ponyint_asio_init(uint32_t cpu)
 {
   asio_cpu = cpu;
diff --git a/src/libponyrt/asio/asio.h b/src/libponyrt/asio/asio.h
index 618a9759f5..36cd173512 100644
--- a/src/libponyrt/asio/asio.h
+++ b/src/libponyrt/asio/asio.h
@@ -68,6 +68,11 @@ bool ponyint_asio_start();
  */
 asio_backend_t* ponyint_asio_get_backend();
 
+/** Returns the cpu assigned for the ASIO thread.
+ *
+ */
+uint32_t ponyint_asio_get_cpu();
+
 /** Attempts to stop an asynchronous event mechanism.
  *
  * Stopping an event mechanism is only possible if there are no pending "noisy"
diff --git a/src/libponyrt/asio/epoll.c b/src/libponyrt/asio/epoll.c
index 8443e79a28..17b6612b80 100644
--- a/src/libponyrt/asio/epoll.c
+++ b/src/libponyrt/asio/epoll.c
@@ -6,6 +6,7 @@
 
 #include "../actor/messageq.h"
 #include "../mem/pool.h"
+#include "../sched/cpu.h"
 #include <sys/epoll.h>
 #include <sys/eventfd.h>
 #include <sys/timerfd.h>
@@ -163,6 +164,7 @@ PONY_API void pony_asio_event_resubscribe_read(asio_event_t* ev)
 
 DECLARE_THREAD_FN(ponyint_asio_backend_dispatch)
 {
+  ponyint_cpu_affinity(ponyint_asio_get_cpu());
   pony_register_thread();
   asio_backend_t* b = arg;
 
diff --git a/src/libponyrt/asio/iocp.c b/src/libponyrt/asio/iocp.c
index f5672da875..7e36630a2d 100644
--- a/src/libponyrt/asio/iocp.c
+++ b/src/libponyrt/asio/iocp.c
@@ -7,6 +7,7 @@
 
 #include "../actor/messageq.h"
 #include "../mem/pool.h"
+#include "../sched/cpu.h"
 #include <string.h>
 #include <signal.h>
 #include <stdbool.h>
@@ -101,6 +102,7 @@ void ponyint_asio_backend_final(asio_backend_t* b)
 
 DECLARE_THREAD_FN(ponyint_asio_backend_dispatch)
 {
+  ponyint_cpu_affinity(ponyint_asio_get_cpu());
   pony_register_thread();
   asio_backend_t* b = (asio_backend_t*)arg;
   asio_event_t* stdin_event = NULL;
diff --git a/src/libponyrt/asio/kqueue.c b/src/libponyrt/asio/kqueue.c
index 794ee26f69..8c9206e944 100644
--- a/src/libponyrt/asio/kqueue.c
+++ b/src/libponyrt/asio/kqueue.c
@@ -4,6 +4,7 @@
 
 #include "../actor/messageq.h"
 #include "../mem/pool.h"
+#include "../sched/cpu.h"
 #include "ponyassert.h"
 #include <sys/event.h>
 #include <string.h>
@@ -120,6 +121,7 @@ PONY_API void pony_asio_event_resubscribe_write(asio_event_t* ev)
 
 DECLARE_THREAD_FN(ponyint_asio_backend_dispatch)
 {
+  ponyint_cpu_affinity(ponyint_asio_get_cpu());
   pony_register_thread();
   asio_backend_t* b = arg;
   struct kevent fired[MAX_EVENTS];
diff --git a/src/libponyrt/platform/threads.c b/src/libponyrt/platform/threads.c
index 5b8e1a980f..e23d990791 100644
--- a/src/libponyrt/platform/threads.c
+++ b/src/libponyrt/platform/threads.c
@@ -176,8 +176,6 @@ bool ponyint_thread_create(pony_thread_id_t* thread, thread_fn start,
     CPU_ZERO(&set);
     CPU_SET(cpu, &set);
 
-    pthread_attr_setaffinity_np(&attr, sizeof(cpu_set_t), &set);
-
     if(use_numa)
     {
       struct rlimit limit;
diff --git a/src/libponyrt/sched/cpu.c b/src/libponyrt/sched/cpu.c
index d9e897c0ae..df6f28af87 100644
--- a/src/libponyrt/sched/cpu.c
+++ b/src/libponyrt/sched/cpu.c
@@ -256,7 +256,11 @@ void ponyint_cpu_affinity(uint32_t cpu)
     return;
 
 #if defined(PLATFORM_IS_LINUX)
-  // Affinity is handled when spawning the thread.
+    cpu_set_t set;
+    CPU_ZERO(&set);
+    CPU_SET(cpu, &set);
+
+    sched_setaffinity(0, sizeof(cpu_set_t), &set);
 #elif defined(PLATFORM_IS_FREEBSD)
   // No pinning, since we cannot yet determine hyperthreads vs physical cores.
 #elif defined(PLATFORM_IS_MACOSX)
diff --git a/src/libponyrt/sched/scheduler.c b/src/libponyrt/sched/scheduler.c
index f46bfbf2fd..917520b54a 100644
--- a/src/libponyrt/sched/scheduler.c
+++ b/src/libponyrt/sched/scheduler.c
@@ -12,7 +12,7 @@
 #include <string.h>
 #include <stdio.h>
 
-#define SCHED_BATCH 100
+#define PONY_SCHED_BATCH 100
 
 static DECLARE_THREAD_FN(run_thread);
 
@@ -284,7 +284,7 @@ static void run(scheduler_t* sched)
     }
 
     // Run the current actor and get the next actor.
-    bool reschedule = ponyint_actor_run(&sched->ctx, actor, SCHED_BATCH);
+    bool reschedule = ponyint_actor_run(&sched->ctx, actor, PONY_SCHED_BATCH);
     pony_actor_t* next = pop_global(sched);
 
     if(reschedule)
@@ -370,6 +370,7 @@ static void ponyint_sched_shutdown()
 pony_ctx_t* ponyint_sched_init(uint32_t threads, bool noyield, bool nopin,
   bool pinasio)
 {
+  this_scheduler = NULL;
   pony_register_thread();
   this_scheduler->ctx.current = NULL;