package net.openhft.chronicle.bytes;

public interface ByteStringAppender<B extends ByteStringAppender<B>> extends StreamingDataOutput<B> {
    default B append(char ch) {
        BytesUtil.appendUTF(this, ch);
        return (B) this;
    }

    default B append(CharSequence cs) {
        return append(cs, 0, cs.length());
    }

    default B append(long value) {
        BytesUtil.append(this, value);
        return (B) this;
    }

    default B append(float f) {
        BytesUtil.append(this, f);
        return (B) this;
    }

    default B append(double d) {
        BytesUtil.append(this, d);
        return (B) this;
    }

    default B append(CharSequence cs, int start, int end) {
        BytesUtil.appendUTF(this, cs, start, end - start);
        return (B) this;
    }

    default B append(long value, int digits) {
        BytesUtil.append((RandomDataOutput) this, position(), value, digits);
        this.skip(digits);
        return (B) this;
    }

}

package net.openhft.chronicle.bytes;

public interface ByteStringAppender<B extends ByteStringAppender<B>> extends StreamingDataOutput<B> {
    default B append(char ch) {
        BytesUtil.appendUTF(this, ch);
        return (B) this;
    }

    default B append(CharSequence cs) {
        return append(cs, 0, cs.length());
    }

    default B append(long value) {
        BytesUtil.append(this, value);
        return (B) this;
    }

    default B append(float f) {
        BytesUtil.append(this, f);
        return (B) this;
    }

    default B append(double d) {
        BytesUtil.append(this, d);
        return (B) this;
    }

    default B append(CharSequence cs, int start, int end) {
        BytesUtil.appendUTF(this, cs, start, end - start);
        return (B) this;
    }
}

--- 
+++ 
@@ -29,4 +29,11 @@
         BytesUtil.appendUTF(this, cs, start, end - start);
         return (B) this;
     }
+
+    default B append(long value, int digits) {
+        BytesUtil.append((RandomDataOutput) this, position(), value, digits);
+        this.skip(digits);
+        return (B) this;
+    }
+
 }
Add support for text based LongArrayTextReference
