diff --git a/core/auxiliary.go b/core/auxiliary.go
index 7d3321e..ea4fb70 100644
--- a/core/auxiliary.go
+++ b/core/auxiliary.go
@@ -2,8 +2,6 @@ package core
 
 import (
 	"os"
-	"reflect"
-	"unsafe"
 )
 
 var (
@@ -15,9 +13,3 @@ var (
 func roundToPageSize(length int) int {
 	return (length + (pageSize - 1)) & (^(pageSize - 1))
 }
-
-// Convert a pointer and length to a byte slice that describes that memory.
-func getBytes(ptr *byte, len int) []byte {
-	var sl = reflect.SliceHeader{Data: uintptr(unsafe.Pointer(ptr)), Len: len, Cap: len}
-	return *(*[]byte)(unsafe.Pointer(&sl))
-}
diff --git a/core/auxiliary_test.go b/core/auxiliary_test.go
index 67b5432..793eecd 100644
--- a/core/auxiliary_test.go
+++ b/core/auxiliary_test.go
@@ -1,10 +1,8 @@
 package core
 
 import (
-	"bytes"
 	"fmt"
 	"testing"
-	"unsafe"
 )
 
 func TestRoundToPageSize(t *testing.T) {
@@ -23,31 +21,3 @@ func TestRoundToPageSize(t *testing.T) {
 		t.Error("failed with test input page_size + 1")
 	}
 }
-
-func TestGetBytes(t *testing.T) {
-	// Allocate an ordinary buffer.
-	buffer := make([]byte, 32)
-
-	// Get am alternate reference to it using our slice builder.
-	derived := getBytes(&buffer[0], len(buffer))
-
-	// Check for naive equality.
-	if !bytes.Equal(buffer, derived) {
-		t.Error("naive equality check failed")
-	}
-
-	// Modify and check if the change was reflected in both.
-	buffer[0] = 1
-	buffer[31] = 1
-	if !bytes.Equal(buffer, derived) {
-		t.Error("modified equality check failed")
-	}
-
-	// Do a deep comparison.
-	if uintptr(unsafe.Pointer(&buffer[0])) != uintptr(unsafe.Pointer(&derived[0])) {
-		t.Error("pointer values differ")
-	}
-	if len(buffer) != len(derived) || cap(buffer) != cap(derived) {
-		t.Error("length or capacity values differ")
-	}
-}
diff --git a/core/buffer.go b/core/buffer.go
index afea842..fd10029 100644
--- a/core/buffer.go
+++ b/core/buffer.go
@@ -3,6 +3,7 @@ package core
 import (
 	"errors"
 	"sync"
+	"unsafe"
 
 	"github.com/awnumar/memcall"
 )
@@ -58,15 +59,15 @@ func NewBuffer(size int) (*Buffer, error) {
 	}
 
 	// Construct slice reference for data buffer.
-	b.data = getBytes(&b.memory[pageSize+innerLen-size], size)
+	b.data = unsafe.Slice(&b.memory[pageSize+innerLen-size], size)
 
 	// Construct slice references for page sectors.
-	b.preguard = getBytes(&b.memory[0], pageSize)
-	b.inner = getBytes(&b.memory[pageSize], innerLen)
-	b.postguard = getBytes(&b.memory[pageSize+innerLen], pageSize)
+	b.preguard = unsafe.Slice(&b.memory[0], pageSize)
+	b.inner = unsafe.Slice(&b.memory[pageSize], innerLen)
+	b.postguard = unsafe.Slice(&b.memory[pageSize+innerLen], pageSize)
 
 	// Construct slice reference for canary portion of inner page.
-	b.canary = getBytes(&b.memory[pageSize], len(b.inner)-len(b.data))
+	b.canary = unsafe.Slice(&b.memory[pageSize], len(b.inner)-len(b.data))
 
 	// Lock the pages that will hold sensitive data.
 	if err := memcall.Lock(b.inner); err != nil {
diff --git a/core/coffer_test.go b/core/coffer_test.go
index ecb6acd..297365a 100644
--- a/core/coffer_test.go
+++ b/core/coffer_test.go
@@ -2,9 +2,7 @@ package core
 
 import (
 	"bytes"
-	"context"
-	"os"
-	"strconv"
+	"math/rand/v2"
 	"sync"
 	"testing"
 	"time"
@@ -176,24 +174,10 @@ func TestCofferDestroy(t *testing.T) {
 }
 
 func TestCofferConcurrent(t *testing.T) {
-	testConcurrency := 3
-	envVar := os.Getenv("TEST_CONCURRENCY")
-	if len(envVar) > 0 {
-		envVarValue, err := strconv.Atoi(envVar)
-		if envVarValue > 0 {
-			testConcurrency = envVarValue
-			t.Logf("test concurrency set to %v", testConcurrency)
-		} else {
-			t.Logf("cannot use test concurrency %v: %v", envVar, err)
-		}
-	}
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
+	testConcurrency := 10
+	testDuration := 2 * time.Second
 
 	funcs := []func(s *Coffer) error{
-		func(s *Coffer) error {
-			return s.Init()
-		},
 		func(s *Coffer) error {
 			return s.Rekey()
 		},
@@ -204,39 +188,30 @@ func TestCofferConcurrent(t *testing.T) {
 	}
 	wg := &sync.WaitGroup{}
 
-	for _, fn := range funcs {
-		for i := 0; i != testConcurrency; i++ {
-			s := NewCoffer()
-			wg.Add(1)
-
-			go func(ctx context.Context, wg *sync.WaitGroup, s *Coffer, target func(s *Coffer) error) {
-				defer wg.Done()
-				for {
-					select {
-					case <-time.After(time.Millisecond):
-						err := target(s)
-						if err != nil {
-							if err == ErrCofferExpired {
-								return
-							}
-							t.Fatalf("unexpected error: %v", err)
-						}
-					case <-ctx.Done():
-						return
-					}
+	s := NewCoffer()
+	defer s.Destroy()
+
+	start := time.Now()
+
+	for range testConcurrency {
+		wg.Add(1)
+		go func(t *testing.T) {
+			defer wg.Done()
+			defer func() {
+				if r := recover(); r != nil {
+					// Log panic -- it's likely just ran out of mlock space.
+					t.Logf("Recovered from panic: %s", r)
 				}
-			}(ctx, wg, s, fn)
-
-			wg.Add(1)
-			go func(ctx context.Context, wg *sync.WaitGroup, s *Coffer, i int) {
-				defer wg.Done()
-				select {
-				case <-time.After(time.Duration(i) * time.Millisecond):
-				case <-ctx.Done():
+			}()
+			fIndex := rand.IntN(len(funcs))
+			for time.Since(start) < testDuration {
+				err := funcs[fIndex](s)
+				if err != nil && err != ErrCofferExpired {
+					t.Errorf("unexpected error: %v", err)
 				}
-				s.Destroy()
-			}(ctx, wg, s, i)
-		}
+			}
+		}(t)
 	}
+
 	wg.Wait()
 }