diff --git a/engine.go b/engine.go
index 0f32493..bb21ff5 100644
--- a/engine.go
+++ b/engine.go
@@ -28,7 +28,7 @@ func (e *Engine) RegisterBlock(name string, td Renderer) {
 		if err != nil {
 			return err
 		}
-		_, err = w.Write([]byte(s))
+		_, err = io.WriteString(w, s)
 		return err
 	})
 }
@@ -60,7 +60,7 @@ func (e *Engine) RegisterTag(name string, td Renderer) {
 			if err != nil {
 				return err
 			}
-			_, err = w.Write([]byte(s))
+			_, err = io.WriteString(w, s)
 			return err
 		}, nil
 	})
diff --git a/render/context_test.go b/render/context_test.go
index 550ac79..be3cdfa 100644
--- a/render/context_test.go
+++ b/render/context_test.go
@@ -16,19 +16,19 @@ func addContextTestTags(s Config) {
 		if err != nil {
 			return err
 		}
-		_, err = w.Write([]byte(fmt.Sprint(v)))
+		_, err = fmt.Fprint(w, v)
 		return err
 	})
 	s.AddBlock("parse").Compiler(func(c BlockNode) (func(io.Writer, Context) error, error) {
 		a := c.Args
 		return func(w io.Writer, c Context) error {
-			_, err := w.Write([]byte(a))
+			_, err := io.WriteString(w, a)
 			return err
 		}, nil
 	})
 	s.AddTag("tag_name", func(string) (func(io.Writer, Context) error, error) {
 		return func(w io.Writer, c Context) error {
-			_, err := w.Write([]byte(c.TagName()))
+			_, err := io.WriteString(w, c.TagName())
 			return err
 		}, nil
 	})
@@ -38,7 +38,7 @@ func addContextTestTags(s Config) {
 			if err != nil {
 				return err
 			}
-			_, err = w.Write([]byte(s))
+			_, err = io.WriteString(w, s)
 			return err
 		}, nil
 	})
diff --git a/render/render.go b/render/render.go
index 01cd18e..5e5b423 100644
--- a/render/render.go
+++ b/render/render.go
@@ -30,7 +30,7 @@ func (n *BlockNode) render(w io.Writer, ctx nodeContext) Error {
 
 func (n *RawNode) render(w io.Writer, ctx nodeContext) Error {
 	for _, s := range n.slices {
-		_, err := w.Write([]byte(s))
+		_, err := io.WriteString(w, s)
 		if err != nil {
 			return wrapRenderError(err, n)
 		}
@@ -60,7 +60,7 @@ func (n *TagNode) render(w io.Writer, ctx nodeContext) Error {
 }
 
 func (n *TextNode) render(w io.Writer, ctx nodeContext) Error {
-	_, err := w.Write([]byte(n.Source))
+	_, err := io.WriteString(w, n.Source)
 	return wrapRenderError(err, n)
 }
 
@@ -83,7 +83,7 @@ func writeObject(value interface{}, w io.Writer) error {
 		}
 		return nil
 	default:
-		_, err := w.Write([]byte(fmt.Sprint(value)))
+		_, err := io.WriteString(w, fmt.Sprint(value))
 		return err
 	}
 }
diff --git a/tags/include_tag.go b/tags/include_tag.go
index 76108d4..6442a24 100644
--- a/tags/include_tag.go
+++ b/tags/include_tag.go
@@ -25,7 +25,7 @@ func includeTag(source string) (func(io.Writer, render.Context) error, error) {
 		if err != nil {
 			return err
 		}
-		_, err = w.Write([]byte(s))
+		_, err = io.WriteString(w, s)
 		return err
 	}, nil
 }
diff --git a/tags/iteration_tags.go b/tags/iteration_tags.go
index a2f776a..6240c39 100644
--- a/tags/iteration_tags.go
+++ b/tags/iteration_tags.go
@@ -51,7 +51,7 @@ func cycleTag(args string) (func(io.Writer, render.Context) error, error) {
 		n := cycleMap[group]
 		cycleMap[group] = n + 1
 		// The parser guarantees that there will be at least one item.
-		_, err = w.Write([]byte(values[n%len(values)]))
+		_, err = io.WriteString(w, values[n%len(values)])
 		return err
 	}, nil
 }