diff --git a/README.md b/README.md
index 825a420..c0c1cc8 100644
--- a/README.md
+++ b/README.md
@@ -4,10 +4,10 @@
 
 A curated collection of utility functions and types absent from the Go standard library that make life easier.
 
-See documentation: https://pkg.go.dev/github.com/jpfourny/papaya
+See documentation: https://pkg.go.dev/github.com/jpfourny/papaya/v2
 
 See tests and examples for usage.
 
 ## Installation
 
-`go get github.com/jpfourny/papaya`
+`go get github.com/jpfourny/papaya/v2`
diff --git a/examples/people.go b/examples/people.go
index 95eb756..9e242cd 100644
--- a/examples/people.go
+++ b/examples/people.go
@@ -3,7 +3,7 @@ package examples
 import (
 	"fmt"
 
-	"github.com/jpfourny/papaya/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
 )
 
 type Person struct {
diff --git a/examples/stream/map_test.go b/examples/stream/map_test.go
index f11633f..39d36d4 100644
--- a/examples/stream/map_test.go
+++ b/examples/stream/map_test.go
@@ -2,11 +2,11 @@ package stream
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/stream"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/stream"
 )
 
 func TestMapIntToString(t *testing.T) {
diff --git a/examples/stream/sort_test.go b/examples/stream/sort_test.go
index 709690a..e002057 100644
--- a/examples/stream/sort_test.go
+++ b/examples/stream/sort_test.go
@@ -4,9 +4,9 @@ import (
 	"fmt"
 	"testing"
 
-	"github.com/jpfourny/papaya/examples"
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/stream"
+	"github.com/jpfourny/papaya/v2/examples"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/stream"
 )
 
 func TestSort(t *testing.T) {
diff --git a/go.mod b/go.mod
index ed2c543..7a8814d 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
-module github.com/jpfourny/papaya
+module github.com/jpfourny/papaya/v2
 
 go 1.23
diff --git a/internal/kvstore/kvstore.go b/internal/kvstore/kvstore.go
index 18bf085..0053809 100644
--- a/internal/kvstore/kvstore.go
+++ b/internal/kvstore/kvstore.go
@@ -1,8 +1,8 @@
 package kvstore
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 	"slices"
 )
 
diff --git a/internal/kvstore/kvstore_test.go b/internal/kvstore/kvstore_test.go
index 32f8001..ae16857 100644
--- a/internal/kvstore/kvstore_test.go
+++ b/internal/kvstore/kvstore_test.go
@@ -1,9 +1,9 @@
 package kvstore
 
 import (
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 	"testing"
 )
 
diff --git a/pkg/cmp/comparer.go b/pkg/cmp/comparer.go
index 4886811..6d3591b 100644
--- a/pkg/cmp/comparer.go
+++ b/pkg/cmp/comparer.go
@@ -4,8 +4,8 @@ import (
 	stdcmp "cmp"
 	"time"
 
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 // Comparer is a function that compares two values of the same type E and returns an integer.
diff --git a/pkg/cmp/comparer_test.go b/pkg/cmp/comparer_test.go
index 4b5ec9f..305866d 100644
--- a/pkg/cmp/comparer_test.go
+++ b/pkg/cmp/comparer_test.go
@@ -5,8 +5,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/ptr"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/ptr"
 )
 
 type Person struct {
diff --git a/pkg/env/env.go b/pkg/env/env.go
index a25ac5a..1d9e55f 100644
--- a/pkg/env/env.go
+++ b/pkg/env/env.go
@@ -1,11 +1,11 @@
 package env
 
 import (
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/stream"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/stream"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
 	"os"
 	"strings"
 	"time"
diff --git a/pkg/env/env_test.go b/pkg/env/env_test.go
index 82aed32..68d0369 100644
--- a/pkg/env/env_test.go
+++ b/pkg/env/env_test.go
@@ -1,8 +1,8 @@
 package env
 
 import (
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/stream"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/stream"
 	"os"
 	"testing"
 	"time"
diff --git a/pkg/ptr/pointer.go b/pkg/ptr/pointer.go
index 1f3823f..b17001f 100644
--- a/pkg/ptr/pointer.go
+++ b/pkg/ptr/pointer.go
@@ -1,6 +1,6 @@
 package ptr
 
-import "github.com/jpfourny/papaya/pkg/opt"
+import "github.com/jpfourny/papaya/v2/pkg/opt"
 
 // Nil returns a nil pointer to the type parameter V.
 func Nil[V any]() *V {
diff --git a/pkg/res/failure.go b/pkg/res/failure.go
index b43cbac..77f9f8a 100644
--- a/pkg/res/failure.go
+++ b/pkg/res/failure.go
@@ -2,7 +2,7 @@ package res
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // Failure represents a failed result.
diff --git a/pkg/res/partial_success.go b/pkg/res/partial_success.go
index 2500858..40d7a5f 100644
--- a/pkg/res/partial_success.go
+++ b/pkg/res/partial_success.go
@@ -2,7 +2,7 @@ package res
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // PartialSuccess represents a partially-successful result.
diff --git a/pkg/res/result.go b/pkg/res/result.go
index 1ae5bf6..47cf492 100644
--- a/pkg/res/result.go
+++ b/pkg/res/result.go
@@ -2,7 +2,7 @@ package res
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // Result represents the result of an operation that may have a value and/or an error.
diff --git a/pkg/res/success.go b/pkg/res/success.go
index 67edfcb..79f363f 100644
--- a/pkg/res/success.go
+++ b/pkg/res/success.go
@@ -2,7 +2,7 @@ package res
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // Success represents a successful result.
diff --git a/pkg/stream/aggregate.go b/pkg/stream/aggregate.go
index 7059054..69b89a3 100644
--- a/pkg/stream/aggregate.go
+++ b/pkg/stream/aggregate.go
@@ -1,11 +1,11 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
-	"github.com/jpfourny/papaya/pkg/stream/reducer"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/reducer"
 )
 
 // Reducer represents a function that takes two inputs of type E and returns an output of type E.
diff --git a/pkg/stream/aggregate_test.go b/pkg/stream/aggregate_test.go
index db67be0..db3c609 100644
--- a/pkg/stream/aggregate_test.go
+++ b/pkg/stream/aggregate_test.go
@@ -1,10 +1,10 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 func TestReduce(t *testing.T) {
diff --git a/pkg/stream/collect.go b/pkg/stream/collect.go
index 24965d7..824c71e 100644
--- a/pkg/stream/collect.go
+++ b/pkg/stream/collect.go
@@ -2,9 +2,9 @@ package stream
 
 import (
 	"context"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
 
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 // CollectSlice returns a slice containing all elements from the stream.
diff --git a/pkg/stream/collect_test.go b/pkg/stream/collect_test.go
index 7146903..72e2633 100644
--- a/pkg/stream/collect_test.go
+++ b/pkg/stream/collect_test.go
@@ -4,8 +4,8 @@ import (
 	"context"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 func TestCollectSlice(t *testing.T) {
diff --git a/pkg/stream/combine.go b/pkg/stream/combine.go
index 3ed0138..5e7f563 100644
--- a/pkg/stream/combine.go
+++ b/pkg/stream/combine.go
@@ -2,11 +2,11 @@ package stream
 
 import (
 	"context"
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
-	"github.com/jpfourny/papaya/pkg/stream/pred"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/pred"
 )
 
 // Combiner represents a function that combines two elements of type E1 and E2 into an element of type F.
diff --git a/pkg/stream/combine_test.go b/pkg/stream/combine_test.go
index f2d2f63..d20c784 100644
--- a/pkg/stream/combine_test.go
+++ b/pkg/stream/combine_test.go
@@ -4,9 +4,9 @@ import (
 	"fmt"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 func TestCombine(t *testing.T) {
diff --git a/pkg/stream/consumer.go b/pkg/stream/consumer.go
new file mode 100644
index 0000000..c2d1171
--- /dev/null
+++ b/pkg/stream/consumer.go
@@ -0,0 +1,18 @@
+package stream
+
+// Consumer represents a function that accepts a yielded element of type E and returns a boolean value.
+// The boolean value indicates whether the consumer wishes to continue accepting elements.
+// If the consumer returns false, the caller must stop yielding elements.
+type Consumer[E any] func(yield E) (cont bool)
+
+func stopSensingConsumer[E any](c Consumer[E]) (Consumer[E], *bool) {
+	stopped := new(bool)
+	c2 := func(e E) bool {
+		if c(e) {
+			return true
+		}
+		*stopped = true
+		return false
+	}
+	return c2, stopped
+}
diff --git a/pkg/stream/consumer_test.go b/pkg/stream/consumer_test.go
new file mode 100644
index 0000000..407cced
--- /dev/null
+++ b/pkg/stream/consumer_test.go
@@ -0,0 +1,44 @@
+package stream
+
+import (
+	"slices"
+	"testing"
+)
+
+func Test_stopSensingConsumer(t *testing.T) {
+	t.Run("stream-exhausted", func(t *testing.T) {
+		s := Of(1, 2, 3)
+		var saw []int
+		c1 := func(e int) bool {
+			saw = append(saw, e)
+			return true
+		}
+		c2, stopped := stopSensingConsumer(c1)
+		s(c2)
+		if *stopped {
+			t.Errorf("expected stopped to be false; got true")
+		}
+		want := []int{1, 2, 3}
+		if !slices.Equal(saw, want) {
+			t.Errorf("expected to see %v; got %v", want, saw)
+		}
+	})
+
+	t.Run("consumer-stopped", func(t *testing.T) {
+		s := Of(1, 2, 3)
+		var saw []int
+		c1 := func(e int) bool {
+			saw = append(saw, e)
+			return false
+		}
+		c2, stopped := stopSensingConsumer(c1)
+		s(c2)
+		if !*stopped {
+			t.Errorf("expected stopped to be true; got false")
+		}
+		want := []int{1}
+		if !slices.Equal(saw, want) {
+			t.Errorf("expected to see %v; got %v", want, saw)
+		}
+	})
+}
diff --git a/pkg/stream/filter.go b/pkg/stream/filter.go
index 79e5b9f..45b8594 100644
--- a/pkg/stream/filter.go
+++ b/pkg/stream/filter.go
@@ -1,9 +1,9 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/kvstore"
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/internal/kvstore"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 // Predicate is a function that accepts a value of type E and returns a boolean.
diff --git a/pkg/stream/filter_test.go b/pkg/stream/filter_test.go
index 6986e81..92066c0 100644
--- a/pkg/stream/filter_test.go
+++ b/pkg/stream/filter_test.go
@@ -1,11 +1,11 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
 )
 
 func TestFilter(t *testing.T) {
diff --git a/pkg/stream/from.go b/pkg/stream/from.go
index f1e7886..476b6e9 100644
--- a/pkg/stream/from.go
+++ b/pkg/stream/from.go
@@ -3,7 +3,7 @@ package stream
 import (
 	"context"
 
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 // FromSlice creates a stream that iterates over the elements of the given slice.
diff --git a/pkg/stream/from_test.go b/pkg/stream/from_test.go
index 9d73fb2..77a89dc 100644
--- a/pkg/stream/from_test.go
+++ b/pkg/stream/from_test.go
@@ -6,8 +6,8 @@ import (
 	"sync"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 func TestFromSlice(t *testing.T) {
diff --git a/pkg/stream/generate_test.go b/pkg/stream/generate_test.go
index 0e916b9..f673c3a 100644
--- a/pkg/stream/generate_test.go
+++ b/pkg/stream/generate_test.go
@@ -1,7 +1,7 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
 	"math/rand"
 	"testing"
 )
diff --git a/pkg/stream/group.go b/pkg/stream/group.go
index 7f5b55a..c31af1a 100644
--- a/pkg/stream/group.go
+++ b/pkg/stream/group.go
@@ -1,11 +1,11 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/kvstore"
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/internal/kvstore"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
 )
 
 // GroupByKey returns a stream that values key-value pairs by key.
diff --git a/pkg/stream/group_test.go b/pkg/stream/group_test.go
index ad4c696..fc47c1d 100644
--- a/pkg/stream/group_test.go
+++ b/pkg/stream/group_test.go
@@ -4,8 +4,8 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 )
 
 func TestGroupByKey(t *testing.T) {
diff --git a/pkg/stream/iter.go b/pkg/stream/iter.go
index 0e683d6..890cf69 100644
--- a/pkg/stream/iter.go
+++ b/pkg/stream/iter.go
@@ -1,7 +1,7 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 	"iter"
 )
 
diff --git a/pkg/stream/iter_test.go b/pkg/stream/iter_test.go
index 3bce647..a9d8f96 100644
--- a/pkg/stream/iter_test.go
+++ b/pkg/stream/iter_test.go
@@ -1,8 +1,8 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/pair"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 	"maps"
 	"slices"
 	"testing"
@@ -23,5 +23,5 @@ func TestFromIterSeq2(t *testing.T) {
 		pair.Of(3, 4),
 		pair.Of(5, 6),
 	}
-	assert.ElementsMatch(t, got, want)
+	assert.ElementsMatchAnyOrder(t, got, want)
 }
diff --git a/pkg/stream/map.go b/pkg/stream/map.go
index e14bc4b..2c30712 100644
--- a/pkg/stream/map.go
+++ b/pkg/stream/map.go
@@ -1,7 +1,7 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // Mapper represents a function that transforms an input of type E to an output of type F.
@@ -66,18 +66,11 @@ type StreamMapper[E, F any] func(from E) (to Stream[F])
 //	out := stream.DebugString(s) // "<1, 1, 2, 2, 3, 3>"
 func FlatMap[E, F any](s Stream[E], m StreamMapper[E, F]) Stream[F] {
 	return func(yield Consumer[F]) {
-		stopped := false
-		yield2 := func(f F) bool { // Stop-sensing consumer.
-			if yield(f) {
-				return true
-			}
-			stopped = true
-			return false
-		}
+		yield2, stopped := stopSensingConsumer(yield)
 
 		s(func(e E) bool {
 			m(e)(yield2)
-			if stopped {
+			if *stopped {
 				return false // Consumer saw enough.
 			}
 			return true
@@ -104,17 +97,10 @@ type SliceMapper[E, F any] func(from E) (to []F)
 func FlatMapSlice[E, F any](s Stream[E], m SliceMapper[E, F]) Stream[F] {
 	return func(yield Consumer[F]) {
 		s(func(e E) bool {
-			stopped := false
-			yield2 := func(f F) bool { // Stop-sensing consumer.
-				if yield(f) {
-					return true
-				}
-				stopped = true
-				return false
-			}
+			yield2, stopped := stopSensingConsumer(yield)
 
 			FromSlice(m(e))(yield2)
-			if stopped {
+			if *stopped {
 				return false // Consumer saw enough.
 			}
 			return true
diff --git a/pkg/stream/map_test.go b/pkg/stream/map_test.go
index 636f703..53816c5 100644
--- a/pkg/stream/map_test.go
+++ b/pkg/stream/map_test.go
@@ -2,10 +2,10 @@ package stream
 
 import (
 	"fmt"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
 )
 
 func TestMap(t *testing.T) {
diff --git a/pkg/stream/mapper/condition.go b/pkg/stream/mapper/condition.go
index 24c9fe9..af40cea 100644
--- a/pkg/stream/mapper/condition.go
+++ b/pkg/stream/mapper/condition.go
@@ -1,6 +1,6 @@
 package mapper
 
-import "github.com/jpfourny/papaya/pkg/opt"
+import "github.com/jpfourny/papaya/v2/pkg/opt"
 
 // If returns a function that accepts a value of any type E and returns the result of calling the `ifTrue` function as an opt.Optional or an empty opt, if the `cond` function returns false.
 //
diff --git a/pkg/stream/mapper/condition_test.go b/pkg/stream/mapper/condition_test.go
index aec32fa..66e56b4 100644
--- a/pkg/stream/mapper/condition_test.go
+++ b/pkg/stream/mapper/condition_test.go
@@ -1,10 +1,10 @@
 package mapper
 
 import (
-	"github.com/jpfourny/papaya/pkg/stream/pred"
+	"github.com/jpfourny/papaya/v2/pkg/stream/pred"
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 func TestIf(t *testing.T) {
diff --git a/pkg/stream/mapper/convert.go b/pkg/stream/mapper/convert.go
index b35184a..bcf8550 100644
--- a/pkg/stream/mapper/convert.go
+++ b/pkg/stream/mapper/convert.go
@@ -1,6 +1,6 @@
 package mapper
 
-import "github.com/jpfourny/papaya/pkg/constraint"
+import "github.com/jpfourny/papaya/v2/pkg/constraint"
 
 // BoolToBool returns a function that accepts a value of boolean type E and returns a value of boolean type F.
 func BoolToBool[E constraint.Boolean, F constraint.Boolean]() func(E) F {
diff --git a/pkg/stream/mapper/format.go b/pkg/stream/mapper/format.go
index 9b3b39b..3160dcd 100644
--- a/pkg/stream/mapper/format.go
+++ b/pkg/stream/mapper/format.go
@@ -4,7 +4,7 @@ import (
 	"fmt"
 	"strconv"
 
-	"github.com/jpfourny/papaya/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
 )
 
 // Sprint returns a function that accepts a value of any type and returns the result of calling fmt.Sprint on it.
diff --git a/pkg/stream/mapper/misc.go b/pkg/stream/mapper/misc.go
index bf9494c..634397e 100644
--- a/pkg/stream/mapper/misc.go
+++ b/pkg/stream/mapper/misc.go
@@ -1,6 +1,6 @@
 package mapper
 
-import "github.com/jpfourny/papaya/pkg/constraint"
+import "github.com/jpfourny/papaya/v2/pkg/constraint"
 
 // Identity returns a function that accepts a value of any type E and returns that value.
 func Identity[E any]() func(E) E {
diff --git a/pkg/stream/mapper/parse.go b/pkg/stream/mapper/parse.go
index 5de5912..c819dd4 100644
--- a/pkg/stream/mapper/parse.go
+++ b/pkg/stream/mapper/parse.go
@@ -4,8 +4,8 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 // TryParseBool returns a function that accepts a value of any string type and returns the result of calling strconv.ParseBool on it.
diff --git a/pkg/stream/mapper/parse_test.go b/pkg/stream/mapper/parse_test.go
index f9eae35..f38edb1 100644
--- a/pkg/stream/mapper/parse_test.go
+++ b/pkg/stream/mapper/parse_test.go
@@ -4,7 +4,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 func TestTryParseBool(t *testing.T) {
diff --git a/pkg/stream/mapper/pointer.go b/pkg/stream/mapper/pointer.go
index fedd0d7..021455e 100644
--- a/pkg/stream/mapper/pointer.go
+++ b/pkg/stream/mapper/pointer.go
@@ -1,8 +1,8 @@
 package mapper
 
 import (
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/ptr"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/ptr"
 )
 
 // PtrRef returns a function that accepts a value of type V and returns a pointer to a copy of the value (on the heap).
diff --git a/pkg/stream/mapper/pointer_test.go b/pkg/stream/mapper/pointer_test.go
index 0aa6dd1..172270e 100644
--- a/pkg/stream/mapper/pointer_test.go
+++ b/pkg/stream/mapper/pointer_test.go
@@ -3,8 +3,8 @@ package mapper
 import (
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/ptr"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/ptr"
 )
 
 func TestPtrRef(t *testing.T) {
diff --git a/pkg/stream/match.go b/pkg/stream/match.go
index 8ab1ba0..3b26d76 100644
--- a/pkg/stream/match.go
+++ b/pkg/stream/match.go
@@ -2,9 +2,9 @@ package stream
 
 import (
 	"context"
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/stream/pred"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/stream/pred"
 )
 
 // AnyMatch returns true if any element in the stream matches the given Predicate.
diff --git a/pkg/stream/match_test.go b/pkg/stream/match_test.go
index 1e36688..f2cf06e 100644
--- a/pkg/stream/match_test.go
+++ b/pkg/stream/match_test.go
@@ -1,7 +1,7 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
 	"testing"
 )
 
diff --git a/pkg/stream/misc.go b/pkg/stream/misc.go
index 6a773c2..b3c8346 100644
--- a/pkg/stream/misc.go
+++ b/pkg/stream/misc.go
@@ -1,10 +1,10 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/constraint"
-	"github.com/jpfourny/papaya/pkg/opt"
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
-	"github.com/jpfourny/papaya/pkg/stream/pred"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/pred"
 	"strings"
 )
 
@@ -165,21 +165,14 @@ func StringJoin(s Stream[string], sep string) string {
 //	out := stream.DebugString(s) // "<1, 2, 3, 0, 0>"
 func Pad[E any](s Stream[E], pad E, length int) Stream[E] {
 	return func(yield Consumer[E]) {
-		stopped := false
-		yield2 := func(e E) bool { // Stop-sensing consumer.
-			if yield(e) {
-				return true
-			}
-			stopped = true
-			return false
-		}
+		yield2, stopped := stopSensingConsumer(yield)
 
 		i := 0
 		s(func(e E) bool {
 			i++
 			return yield2(e)
 		})
-		if stopped {
+		if *stopped {
 			return // Consumer saw enough.
 		}
 		for ; i < length; i++ {
diff --git a/pkg/stream/misc_test.go b/pkg/stream/misc_test.go
index 0871f7e..f7597fd 100644
--- a/pkg/stream/misc_test.go
+++ b/pkg/stream/misc_test.go
@@ -1,12 +1,12 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/stream/mapper"
-	"github.com/jpfourny/papaya/pkg/stream/pred"
+	"github.com/jpfourny/papaya/v2/pkg/stream/mapper"
+	"github.com/jpfourny/papaya/v2/pkg/stream/pred"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
-	"github.com/jpfourny/papaya/pkg/opt"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/opt"
 )
 
 func TestForEach(t *testing.T) {
diff --git a/pkg/stream/pred/compare.go b/pkg/stream/pred/compare.go
index b8ca780..f1b1165 100644
--- a/pkg/stream/pred/compare.go
+++ b/pkg/stream/pred/compare.go
@@ -4,8 +4,8 @@ import (
 	"math"
 	"reflect"
 
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
 )
 
 // Equal returns a function that returns true if the provided value is equal to the provided want value.
diff --git a/pkg/stream/pred/compare_test.go b/pkg/stream/pred/compare_test.go
index b76d371..e964ae3 100644
--- a/pkg/stream/pred/compare_test.go
+++ b/pkg/stream/pred/compare_test.go
@@ -3,7 +3,7 @@ package pred
 import (
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/ptr"
+	"github.com/jpfourny/papaya/v2/pkg/ptr"
 )
 
 func TestEqual(t *testing.T) {
diff --git a/pkg/stream/pred/in.go b/pkg/stream/pred/in.go
index b61f705..f2226d5 100644
--- a/pkg/stream/pred/in.go
+++ b/pkg/stream/pred/in.go
@@ -1,6 +1,6 @@
 package pred
 
-import "github.com/jpfourny/papaya/pkg/cmp"
+import "github.com/jpfourny/papaya/v2/pkg/cmp"
 
 // In returns a function that returns true if the provided value is equal to any of the provided want values.
 // It uses the == operator to compare values.
diff --git a/pkg/stream/pred/zero_test.go b/pkg/stream/pred/zero_test.go
index f70b6bc..74432c6 100644
--- a/pkg/stream/pred/zero_test.go
+++ b/pkg/stream/pred/zero_test.go
@@ -3,8 +3,8 @@ package pred
 import (
 	"testing"
 
-	"github.com/jpfourny/papaya/pkg/pair"
-	"github.com/jpfourny/papaya/pkg/ptr"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
+	"github.com/jpfourny/papaya/v2/pkg/ptr"
 )
 
 func TestNil(t *testing.T) {
diff --git a/pkg/stream/reducer/reducer.go b/pkg/stream/reducer/reducer.go
index 3b2fcb6..d9688db 100644
--- a/pkg/stream/reducer/reducer.go
+++ b/pkg/stream/reducer/reducer.go
@@ -1,8 +1,8 @@
 package reducer
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
 )
 
 // Sum returns a function that computes the sum of two given values.
diff --git a/pkg/stream/set.go b/pkg/stream/set.go
index 00d4783..3853950 100644
--- a/pkg/stream/set.go
+++ b/pkg/stream/set.go
@@ -1,8 +1,8 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/kvstore"
-	"github.com/jpfourny/papaya/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/internal/kvstore"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
 )
 
 // Union combines multiple streams into a single stream (concatenation).
@@ -15,18 +15,11 @@ import (
 //	out := stream.DebugString(s) // "<1, 2, 3, 4, 4, 5, 6>"
 func Union[E any](ss ...Stream[E]) Stream[E] {
 	return func(yield Consumer[E]) {
-		stopped := false
-		yield2 := func(e E) bool { // Stop-sensing consumer.
-			if yield(e) {
-				return true
-			}
-			stopped = true
-			return false
-		}
+		yield2, stopped := stopSensingConsumer(yield)
 
 		for _, s := range ss {
 			s(yield2)
-			if stopped {
+			if *stopped {
 				return // Consumer saw enough.
 			}
 		}
diff --git a/pkg/stream/set_test.go b/pkg/stream/set_test.go
index 6f69940..6d71b3f 100644
--- a/pkg/stream/set_test.go
+++ b/pkg/stream/set_test.go
@@ -1,10 +1,10 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
 )
 
 func TestUnion(t *testing.T) {
diff --git a/pkg/stream/sort.go b/pkg/stream/sort.go
index c9a64df..301f015 100644
--- a/pkg/stream/sort.go
+++ b/pkg/stream/sort.go
@@ -1,8 +1,9 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/pkg/cmp"
-	"github.com/jpfourny/papaya/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/cmp"
+	"github.com/jpfourny/papaya/v2/pkg/constraint"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 	"slices"
 )
 
@@ -41,3 +42,113 @@ func SortBy[E any](s Stream[E], compare cmp.Comparer[E]) Stream[E] {
 		FromSlice(sl)(yield)
 	}
 }
+
+// SortKeyAsc returns a stream that sorts the elements by key in ascending order.
+// The elements must be pairs of key and value.
+// The keys must implement the Ordered interface.
+//
+// Example usage:
+//
+//	s := stream.SortKeyAsc(
+//	  stream.Of(
+//	    pair.Of(3, "c"),
+//	    pair.Of(1, "a"),
+//	    pair.Of(2, "b"),
+//	  ),
+//	)
+//	out := stream.DebugString(s) // "<1:a, 2:b, 3:c>"
+func SortKeyAsc[K constraint.Ordered, V any](s Stream[pair.Pair[K, V]]) Stream[pair.Pair[K, V]] {
+	return SortKeyBy(s, cmp.Natural[K]())
+}
+
+// SortKeyDesc returns a stream that sorts the elements by key in descending order.
+// The elements must be pairs of key and value.
+// The keys must implement the Ordered interface.
+//
+// Example usage:
+//
+//	s := stream.SortKeyDesc(
+//	  stream.Of(
+//	    pair.Of(3, "c"),
+//	    pair.Of(1, "a"),
+//	    pair.Of(2, "b"),
+//	  ),
+//	)
+//	out := stream.DebugString(s) // "<3:c, 2:b, 1:a>"
+func SortKeyDesc[K constraint.Ordered, V any](s Stream[pair.Pair[K, V]]) Stream[pair.Pair[K, V]] {
+	return SortKeyBy(s, cmp.Reverse[K]())
+}
+
+// SortKeyBy returns a stream that sorts the elements by key using the given cmp.Comparer.
+// The elements must be pairs of key and value.
+// The order of the elements is determined by the comparer.
+//
+// Example usage:
+//
+//	s := stream.SortKeyBy(
+//	  stream.Of(
+//	    pair.Of(3, "c"),
+//	    pair.Of(1, "a"),
+//	    pair.Of(2, "b"),
+//	  ),
+//	  cmp.Natural[int](),
+//	)
+//	out := stream.DebugString(s) // "<1:a, 2:b, 3:c>"
+func SortKeyBy[K any, V any](s Stream[pair.Pair[K, V]], compare cmp.Comparer[K]) Stream[pair.Pair[K, V]] {
+	return SortBy(s, cmp.ComparingBy(pair.Pair[K, V].First, compare))
+}
+
+// SortValueAsc returns a stream that sorts the elements by value in ascending order.
+// The elements must be pairs of key and value.
+// The values must implement the Ordered interface.
+//
+// Example usage:
+//
+//	s := stream.SortValueAsc(
+//	  stream.Of(
+//	    pair.Of("c", 3),
+//	    pair.Of("a", 1),
+//	    pair.Of("b", 2),
+//	  ),
+//	)
+//	out := stream.DebugString(s) // "a:1, b:2, c:3"
+func SortValueAsc[K any, V constraint.Ordered](s Stream[pair.Pair[K, V]]) Stream[pair.Pair[K, V]] {
+	return SortValueBy(s, cmp.Natural[V]())
+}
+
+// SortValueDesc returns a stream that sorts the elements by value in descending order.
+// The elements must be pairs of key and value.
+// The values must implement the Ordered interface.
+//
+// Example usage:
+//
+//	s := stream.SortValueDesc(
+//	  stream.Of(
+//	    pair.Of("c", 3),
+//	    pair.Of("a", 1),
+//	    pair.Of("b", 2),
+//	  ),
+//	)
+//	out := stream.DebugString(s) // "c:3, b:2, a:1"
+func SortValueDesc[K any, V constraint.Ordered](s Stream[pair.Pair[K, V]]) Stream[pair.Pair[K, V]] {
+	return SortValueBy(s, cmp.Reverse[V]())
+}
+
+// SortValueBy returns a stream that sorts the elements by value using the given cmp.Comparer.
+// The elements must be pairs of key and value.
+// The order of the elements is determined by the comparer.
+//
+// Example usage:
+//
+//	s := stream.SortValueBy(
+//	  stream.Of(
+//	    pair.Of("c", 3),
+//	    pair.Of("a", 1),
+//	    pair.Of("b", 2),
+//	  ),
+//	  cmp.Natural[int](),
+//	)
+//	out := stream.DebugString(s) // "a:1, b:2, c:3"
+func SortValueBy[K any, V any](s Stream[pair.Pair[K, V]], compare cmp.Comparer[V]) Stream[pair.Pair[K, V]] {
+	return SortBy(s, cmp.ComparingBy(pair.Pair[K, V].Second, compare))
+}
diff --git a/pkg/stream/sort_test.go b/pkg/stream/sort_test.go
index b1803e3..3c48a84 100644
--- a/pkg/stream/sort_test.go
+++ b/pkg/stream/sort_test.go
@@ -1,7 +1,8 @@
 package stream
 
 import (
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
+	"github.com/jpfourny/papaya/v2/pkg/pair"
 	"testing"
 )
 
@@ -27,3 +28,18 @@ func TestSortBy(t *testing.T) {
 	want := []int{1, 2, 3}
 	assert.ElementsMatch(t, got, want)
 }
+
+func TestSortKeyAsc(t *testing.T) {
+	s := SortKeyAsc(Of(
+		pair.Of(3, "c"),
+		pair.Of(1, "a"),
+		pair.Of(2, "b"),
+	))
+	got := CollectSlice(s)
+	want := []pair.Pair[int, string]{
+		pair.Of(1, "a"),
+		pair.Of(2, "b"),
+		pair.Of(3, "c"),
+	}
+	assert.ElementsMatch(t, got, want)
+}
diff --git a/pkg/stream/stream.go b/pkg/stream/stream.go
index cc6c6f7..b52552c 100644
--- a/pkg/stream/stream.go
+++ b/pkg/stream/stream.go
@@ -10,11 +10,6 @@ package stream
 // If the stream is exhausted, it must return true.
 type Stream[E any] func(c Consumer[E])
 
-// Consumer represents a function that accepts a yielded element of type E and returns a boolean value.
-// The boolean value indicates whether the consumer wishes to continue accepting elements.
-// If the consumer returns false, the caller must stop yielding elements.
-type Consumer[E any] func(yield E) (cont bool)
-
 // Empty returns a stream that does not contain any elements.
 // It always returns true when invoked with a consumer.
 //
diff --git a/pkg/stream/stream_test.go b/pkg/stream/stream_test.go
index 9c8a672..3075a5d 100644
--- a/pkg/stream/stream_test.go
+++ b/pkg/stream/stream_test.go
@@ -3,7 +3,7 @@ package stream
 import (
 	"testing"
 
-	"github.com/jpfourny/papaya/internal/assert"
+	"github.com/jpfourny/papaya/v2/internal/assert"
 )
 
 func TestEmpty(t *testing.T) {