diff --git a/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Ansi.java b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Ansi.java
index a00b59b..8cb2b35 100644
--- a/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Ansi.java
+++ b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Ansi.java
@@ -1,5 +1,7 @@
 package org.codejive.twinkle.ansi;
 
+import java.io.IOException;
+
 public class Ansi {
     public static final char ESC = '\u001B';
 
@@ -68,22 +70,26 @@ public static String style(Object... styles) {
         if (styles == null || styles.length == 0) {
             return "";
         }
-        return style(new StringBuilder(), styles).toString();
+        try {
+            return style(new StringBuilder(), styles).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    public static StringBuilder style(StringBuilder sb, Object... styles) {
+    public static Appendable style(Appendable appendable, Object... styles) throws IOException {
         if (styles == null || styles.length == 0) {
-            return sb;
+            return appendable;
         }
-        sb.append(CSI);
+        appendable.append(CSI);
         for (int i = 0; i < styles.length; i++) {
-            sb.append(styles[i]);
+            appendable.append(styles[i].toString());
             if (i < styles.length - 1) {
-                sb.append(";");
+                appendable.append(";");
             }
         }
-        sb.append("m");
-        return sb;
+        appendable.append("m");
+        return appendable;
     }
 
     public static String foreground(int index) {
diff --git a/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Printable.java b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Printable.java
new file mode 100644
index 0000000..dd2c3fb
--- /dev/null
+++ b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Printable.java
@@ -0,0 +1,70 @@
+package org.codejive.twinkle.ansi;
+
+import java.io.IOException;
+import org.jspecify.annotations.NonNull;
+
+public interface Printable {
+    /**
+     * Converts the object to an ANSI string, including ANSI escape codes for styles. This method
+     * resets the current style to default at the start of the string.
+     *
+     * @return The ANSI string representation of the object.
+     */
+    @NonNull String toAnsiString();
+
+    /**
+     * Outputs the object as an ANSI string, including ANSI escape codes for styles. This method
+     * resets the current style to default at the start of the output.
+     *
+     * @param appendable The <code>Appendable</code> to write the ANSI output to.
+     * @return The <code>Appendable</code> passed as parameter.
+     */
+    @NonNull Appendable toAnsi(Appendable appendable) throws IOException;
+
+    /**
+     * Converts the object to an ANSI string, including ANSI escape codes for styles. This method
+     * takes into account the provided current style to generate a result that is as efficient as
+     * possible in terms of ANSI codes.
+     *
+     * @param currentStyle The current style to start with.
+     * @return The ANSI string representation of the object.
+     */
+    default @NonNull String toAnsiString(Style currentStyle) {
+        return toAnsiString(currentStyle.state());
+    }
+
+    /**
+     * Outputs the object as an ANSI string, including ANSI escape codes for styles. This method
+     * takes into account the provided current style to generate a result that is as efficient as
+     * possible in terms of ANSI codes.
+     *
+     * @param appendable The <code>Appendable</code> to write the ANSI output to.
+     * @param currentStyle The current style to start with.
+     * @return The <code>Appendable</code> passed as parameter.
+     */
+    default @NonNull Appendable toAnsi(Appendable appendable, Style currentStyle)
+            throws IOException {
+        return toAnsi(appendable, currentStyle.state());
+    }
+
+    /**
+     * Converts the object to an ANSI string, including ANSI escape codes for styles. This method
+     * takes into account the provided current style to generate a result that is as efficient as
+     * possible in terms of ANSI codes.
+     *
+     * @param currentStyleState The current style to start with.
+     * @return The ANSI string representation of the object.
+     */
+    @NonNull String toAnsiString(long currentStyleState);
+
+    /**
+     * Outputs the object as an ANSI string, including ANSI escape codes for styles. This method
+     * takes into account the provided current style to generate a result that is as efficient as
+     * possible in terms of ANSI codes.
+     *
+     * @param appendable The <code>Appendable</code> to write the ANSI output to.
+     * @param currentStyleState The current style to start with.
+     * @return The <code>Appendable</code> passed as parameter.
+     */
+    @NonNull Appendable toAnsi(Appendable appendable, long currentStyleState) throws IOException;
+}
diff --git a/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Style.java b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Style.java
index 843eb0f..80a78f8 100644
--- a/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Style.java
+++ b/twinkle-ansi/src/main/java/org/codejive/twinkle/ansi/Style.java
@@ -1,10 +1,11 @@
 package org.codejive.twinkle.ansi;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import org.jspecify.annotations.NonNull;
 
-public class Style {
+public class Style implements Printable {
     private final long state;
 
     private static final long IDX_BOLD = 0;
@@ -347,27 +348,32 @@ public String toString() {
         return sb.toString();
     }
 
-    public String toAnsiString() {
+    @Override
+    public @NonNull String toAnsiString() {
         return toAnsiString(UNSTYLED);
     }
 
-    public StringBuilder toAnsiString(StringBuilder sb) {
-        return toAnsiString(sb, Style.UNSTYLED);
-    }
-
-    public String toAnsiString(Style currentStyle) {
-        return toAnsiString(currentStyle.state());
-    }
-
-    public StringBuilder toAnsiString(StringBuilder sb, Style currentStyle) {
-        return toAnsiString(sb, currentStyle.state());
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable) throws IOException {
+        try {
+            return toAnsi(appendable, Style.UNSTYLED);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    public String toAnsiString(long currentStyleState) {
-        return toAnsiString(new StringBuilder(), currentStyleState).toString();
+    @Override
+    public @NonNull String toAnsiString(long currentStyleState) {
+        try {
+            return toAnsi(new StringBuilder(), currentStyleState).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    public StringBuilder toAnsiString(StringBuilder sb, long currentStyleState) {
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable, long currentStyleState)
+            throws IOException {
         List<Object> styles = new ArrayList<>();
         if ((currentStyleState & (F_BOLD | F_FAINT)) != (state & (F_BOLD | F_FAINT))) {
             // First we switch to NORMAL to clear both BOLD and FAINT
@@ -426,6 +432,6 @@ public StringBuilder toAnsiString(StringBuilder sb, long currentStyleState) {
         if ((currentStyleState & MASK_BG_COLOR) != (state & MASK_BG_COLOR)) {
             styles.add(bgColor().toAnsiBgArgs());
         }
-        return Ansi.style(sb, styles.toArray());
+        return Ansi.style(appendable, styles.toArray());
     }
 }
diff --git a/twinkle-chart/src/test/java/examples/BarDemo.java b/twinkle-chart/src/test/java/examples/BarDemo.java
index a3b06b2..19f29ac 100644
--- a/twinkle-chart/src/test/java/examples/BarDemo.java
+++ b/twinkle-chart/src/test/java/examples/BarDemo.java
@@ -22,18 +22,18 @@ private static void printSimpleBar() {
         Panel pnl = Panel.of(20, 1);
         Bar b = Bar.bar().setValue(42);
         b.render(pnl);
-        System.out.println(pnl.toString());
+        System.out.println(pnl);
     }
 
     private static void printHorizontalBars() {
         Panel pnl = Panel.of(20, 4);
         FracBarConfig cfg = FracBarConfig.create();
         renderHorizontal(pnl, cfg);
-        System.out.println(pnl.toString());
+        System.out.println(pnl);
 
         cfg.direction(BarConfig.Direction.R2L);
         renderHorizontal(pnl, cfg);
-        System.out.println(pnl.toString());
+        System.out.println(pnl);
     }
 
     private static void renderHorizontal(Panel pnl, FracBarConfig cfg) {
@@ -48,11 +48,11 @@ private static void printVerticalBars() {
         Panel pnl = Panel.of(16, 8);
         FracBarConfig cfg = FracBarConfig.create().direction(BarConfig.Direction.B2T);
         renderVertical(pnl, cfg);
-        System.out.println(pnl.toString());
+        System.out.println(pnl);
 
         cfg.direction(BarConfig.Direction.T2B);
         renderVertical(pnl, cfg);
-        System.out.println(pnl.toString());
+        System.out.println(pnl);
     }
 
     private static void renderVertical(Panel pnl, FracBarConfig cfg) {
diff --git a/twinkle-chart/src/test/java/examples/MathPlotFourDemo.java b/twinkle-chart/src/test/java/examples/MathPlotFourDemo.java
index 4ce9d0c..6ac6930 100644
--- a/twinkle-chart/src/test/java/examples/MathPlotFourDemo.java
+++ b/twinkle-chart/src/test/java/examples/MathPlotFourDemo.java
@@ -1,6 +1,8 @@
 // java
 package examples;
 
+import java.io.IOException;
+import java.io.PrintWriter;
 import java.util.Random;
 import org.codejive.twinkle.ansi.Ansi;
 import org.codejive.twinkle.ansi.Color;
@@ -15,7 +17,7 @@
 import org.jspecify.annotations.NonNull;
 
 public class MathPlotFourDemo {
-    public static void main(String[] args) throws InterruptedException {
+    public static void main(String[] args) throws InterruptedException, IOException {
         Panel pnl = Panel.of(60, 40);
         AnimatingMathPlot p1 = new AnimatingMathPlot(Size.of(30, 20), " Interfering Waves 1 ");
         AnimatingMathPlot p2 = new AnimatingMathPlot(Size.of(30, 20), " Interfering Waves 2 ");
@@ -26,11 +28,12 @@ public static void main(String[] args) throws InterruptedException {
         Canvas v3 = pnl.view(0, 20, 30, 20);
         Canvas v4 = pnl.view(30, 20, 30, 20);
 
-        System.out.print(Ansi.hideCursor());
+        PrintWriter pout = new PrintWriter(System.out);
+        pout.print(Ansi.hideCursor());
         try {
             for (int i = 0; i < 400; i++) {
                 if (i > 0) {
-                    System.out.print(Ansi.cursorMove(Ansi.CURSOR_PREV_LINE, pnl.size().height()));
+                    pout.print(Ansi.cursorMove(Ansi.CURSOR_PREV_LINE, pnl.size().height()));
                 }
 
                 p1.update();
@@ -43,12 +46,13 @@ public static void main(String[] args) throws InterruptedException {
                 p3.render(v3);
                 p4.render(v4);
 
-                System.out.println(pnl.toAnsiString());
+                pnl.toAnsi(pout);
+                pout.println();
 
                 Thread.sleep(20);
             }
         } finally {
-            System.out.print(Ansi.showCursor());
+            pout.print(Ansi.showCursor());
         }
     }
 }
diff --git a/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledBuffer.java b/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledBuffer.java
index 3b2cb83..6be21ad 100644
--- a/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledBuffer.java
+++ b/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledBuffer.java
@@ -1,9 +1,10 @@
 package org.codejive.twinkle.core.text;
 
+import org.codejive.twinkle.ansi.Printable;
 import org.codejive.twinkle.ansi.Style;
 import org.jspecify.annotations.NonNull;
 
-public interface StyledBuffer extends StyledCharSequence {
+public interface StyledBuffer extends StyledCharSequence, Printable {
 
     char REPLACEMENT_CHAR = '\uFFFD';
 
@@ -35,36 +36,6 @@ default int putStringAt(int index, @NonNull Style style, @NonNull CharSequence s
 
     @NonNull StyledBuffer resize(int newSize);
 
-    /**
-     * Converts the buffer to an ANSI string, including ANSI escape codes for styles. This method
-     * resets the current style to default at the start of the string.
-     *
-     * @return The ANSI string representation of the styled buffer.
-     */
-    @NonNull String toAnsiString();
-
-    /**
-     * Converts the buffer to an ANSI string, including ANSI escape codes for styles. This method
-     * takes into account the provided current style to generate a result that is as efficient as
-     * possible in terms of ANSI codes.
-     *
-     * @param currentStyle The current style to start with.
-     * @return The ANSI string representation of the styled buffer.
-     */
-    default @NonNull String toAnsiString(Style currentStyle) {
-        return toAnsiString(currentStyle.state());
-    }
-
-    /**
-     * Converts the buffer to an ANSI string, including ANSI escape codes for styles. This method
-     * takes into account the provided current style to generate a result that is as efficient as
-     * possible in terms of ANSI codes.
-     *
-     * @param currentStyle The current style to start with.
-     * @return The ANSI string representation of the styled buffer.
-     */
-    @NonNull String toAnsiString(long currentStyle);
-
     StyledBuffer EMPTY =
             new StyledCodepointBuffer(0) {
                 @Override
diff --git a/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledCodepointBuffer.java b/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledCodepointBuffer.java
index 86d88b9..425a378 100644
--- a/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledCodepointBuffer.java
+++ b/twinkle-core/src/main/java/org/codejive/twinkle/core/text/StyledCodepointBuffer.java
@@ -1,5 +1,6 @@
 package org.codejive.twinkle.core.text;
 
+import java.io.IOException;
 import org.codejive.twinkle.ansi.Ansi;
 import org.codejive.twinkle.ansi.Style;
 import org.jspecify.annotations.NonNull;
@@ -255,8 +256,17 @@ private boolean outside(int index, int length) {
         // plus 20 extra for escape codes
         int initialCapacity = length() + 20;
         StringBuilder sb = new StringBuilder(initialCapacity);
-        sb.append(Ansi.STYLE_RESET);
-        return toAnsiString(sb, Style.UNSTYLED.state()).toString();
+        try {
+            return toAnsi(sb).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable) throws IOException {
+        appendable.append(Ansi.STYLE_RESET);
+        return toAnsi(appendable, Style.UNSTYLED.state());
     }
 
     /**
@@ -278,22 +288,36 @@ private boolean outside(int index, int length) {
         // plus 20 extra for escape codes
         int initialCapacity = length() + 20;
         StringBuilder sb = new StringBuilder(initialCapacity);
-        return toAnsiString(sb, styleState).toString();
+        try {
+            return toAnsi(sb, styleState).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    private @NonNull StringBuilder toAnsiString(StringBuilder sb, long lastStyleState) {
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable, long lastStyleState)
+            throws IOException {
         for (int i = 0; i < length(); i++) {
             if (styleBuffer[i] != lastStyleState) {
                 Style style = Style.of(styleBuffer[i]);
-                style.toAnsiString(sb, lastStyleState);
+                style.toAnsi(appendable, lastStyleState);
                 lastStyleState = styleBuffer[i];
             }
             int cp = cpBuffer[i];
             if (cp == '\0') {
                 cp = ' ';
             }
-            sb.appendCodePoint(cp);
+            if (Character.isBmpCodePoint(cp)) {
+                appendable.append((char) cp);
+            } else if (Character.isValidCodePoint(cp)) {
+                appendable.append(Character.lowSurrogate(cp));
+                appendable.append(Character.highSurrogate(cp));
+            } else {
+                throw new IllegalArgumentException(
+                        String.format("Not a valid Unicode code point: 0x%X", cp));
+            }
         }
-        return sb;
+        return appendable;
     }
 }
diff --git a/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/Panel.java b/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/Panel.java
index 2cfeb4f..d8f4799 100644
--- a/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/Panel.java
+++ b/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/Panel.java
@@ -1,10 +1,10 @@
 package org.codejive.twinkle.core.widget;
 
-import org.codejive.twinkle.ansi.Style;
+import org.codejive.twinkle.ansi.Printable;
 import org.codejive.twinkle.core.text.StyledBuffer;
 import org.jspecify.annotations.NonNull;
 
-public interface Panel extends Canvas {
+public interface Panel extends Canvas, Printable {
 
     @NonNull Panel resize(@NonNull Size newSize);
 
@@ -16,14 +16,6 @@ public interface Panel extends Canvas {
     @Override
     @NonNull PanelView view(@NonNull Rect rect);
 
-    String toAnsiString();
-
-    default String toAnsiString(Style currentStyle) {
-        return toAnsiString(currentStyle.state());
-    }
-
-    String toAnsiString(long currentStyleState);
-
     static @NonNull Panel of(int width, int height) {
         return of(Size.of(width, height));
     }
diff --git a/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/StyledBufferPanel.java b/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/StyledBufferPanel.java
index bcd9c7e..6ee82f5 100644
--- a/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/StyledBufferPanel.java
+++ b/twinkle-core/src/main/java/org/codejive/twinkle/core/widget/StyledBufferPanel.java
@@ -2,6 +2,7 @@
 
 import static org.codejive.twinkle.core.text.StyledBuffer.REPLACEMENT_CHAR;
 
+import java.io.IOException;
 import org.codejive.twinkle.ansi.Ansi;
 import org.codejive.twinkle.ansi.Style;
 import org.codejive.twinkle.core.text.StyledBuffer;
@@ -206,33 +207,49 @@ public String toString() {
     }
 
     @Override
-    public String toAnsiString() {
+    public @NonNull String toAnsiString() {
         // Assuming only single-width characters for capacity estimation
         // plus 20 extra for escape codes and newline
         int initialCapacity = (size().width() + 20) * size().height();
         StringBuilder sb = new StringBuilder(initialCapacity);
         sb.append(Ansi.STYLE_RESET);
-        return toAnsiString(sb, Style.F_UNSTYLED).toString();
+        try {
+            return toAnsi(sb, Style.F_UNSTYLED).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable) throws IOException {
+        appendable.append(Ansi.STYLE_RESET);
+        return toAnsi(appendable, Style.F_UNSTYLED);
     }
 
     @Override
-    public String toAnsiString(long currentStyleState) {
+    public @NonNull String toAnsiString(long currentStyleState) {
         // Assuming only single-width characters for capacity estimation
         // plus 20 extra for escape codes and newline
         int initialCapacity = (size().width() + 1) * size().height();
         StringBuilder sb = new StringBuilder(initialCapacity);
-        return toAnsiString(sb, currentStyleState).toString();
+        try {
+            return toAnsi(sb, currentStyleState).toString();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
-    private @NonNull StringBuilder toAnsiString(StringBuilder sb, long currentStyleState) {
+    @Override
+    public @NonNull Appendable toAnsi(Appendable appendable, long currentStyleState)
+            throws IOException {
         for (int y = 0; y < size().height(); y++) {
-            sb.append(line(y).toAnsiString(currentStyleState));
+            line(y).toAnsi(appendable, currentStyleState);
             currentStyleState = line(y).styleStateAt(size().width() - 1);
             if (y < size().height() - 1) {
-                sb.append('\n');
+                appendable.append('\n');
             }
         }
-        return sb;
+        return appendable;
     }
 
     public static class StyledBufferPanelView extends StyledBufferPanel implements PanelView {