diff --git a/dist/index.js b/dist/index.js
index a9c4d31..b778f82 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -473,8 +473,7 @@ function createNodeAnchors(doc, prefix) {
     return {
         onAnchor: (source) => {
             aliasObjects.push(source);
-            if (!prevAnchors)
-                prevAnchors = anchorNames(doc);
+            prevAnchors ?? (prevAnchors = anchorNames(doc));
             const anchor = findNewAnchor(prefix, prevAnchors);
             prevAnchors.add(anchor);
             return anchor;
@@ -638,23 +637,36 @@ class Alias extends NodeBase {
      * Resolve the value of this alias within `doc`, finding the last
      * instance of the `source` anchor before this node.
      */
-    resolve(doc) {
+    resolve(doc, ctx) {
+        let nodes;
+        if (ctx?.aliasResolveCache) {
+            nodes = ctx.aliasResolveCache;
+        }
+        else {
+            nodes = [];
+            visit$1(doc, {
+                Node: (_key, node) => {
+                    if (isAlias(node) || hasAnchor(node))
+                        nodes.push(node);
+                }
+            });
+            if (ctx)
+                ctx.aliasResolveCache = nodes;
+        }
         let found = undefined;
-        visit$1(doc, {
-            Node: (_key, node) => {
-                if (node === this)
-                    return visit$1.BREAK;
-                if (node.anchor === this.source)
-                    found = node;
-            }
-        });
+        for (const node of nodes) {
+            if (node === this)
+                break;
+            if (node.anchor === this.source)
+                found = node;
+        }
         return found;
     }
     toJSON(_arg, ctx) {
         if (!ctx)
             return { source: this.source };
         const { anchors, doc, maxAliasCount } = ctx;
-        const source = this.resolve(doc);
+        const source = this.resolve(doc, ctx);
         if (!source) {
             const msg = `Unresolved alias (the anchor must be set before the alias): ${this.source}`;
             throw new ReferenceError(msg);
@@ -773,8 +785,7 @@ function createNode(value, tagName, ctx) {
     if (aliasDuplicateObjects && value && typeof value === 'object') {
         ref = sourceObjects.get(value);
         if (ref) {
-            if (!ref.anchor)
-                ref.anchor = onAnchor(value);
+            ref.anchor ?? (ref.anchor = onAnchor(value));
             return new Alias(ref.anchor);
         }
         else {
@@ -1379,10 +1390,9 @@ function plainString(item, ctx, onComment, onChompKeep) {
         (inFlow && /[[\]{},]/.test(value))) {
         return quotedString(value, ctx);
     }
-    if (!value ||
-        /^[\n\t ,[\]{}#&*!|>'"%@`]|^[?-]$|^[?-][ \t]|[\n:][ \t]|[ \t]\n|[\n\t ]#|[\n\t :]$/.test(value)) {
+    if (/^[\n\t ,[\]{}#&*!|>'"%@`]|^[?-]$|^[?-][ \t]|[\n:][ \t]|[ \t]\n|[\n\t ]#|[\n\t :]$/.test(value)) {
         // not allowed:
-        // - empty string, '-' or '?'
+        // - '-' or '?'
         // - start with an indicator character (except [?:-]) or /[?-] /
         // - '\n ', ': ' or ' \n' anywhere
         // - '#' not preceded by a non-space char
@@ -1525,7 +1535,7 @@ function getTagObject(tags, item) {
         tagObj = tags.find(t => t.nodeClass && obj instanceof t.nodeClass);
     }
     if (!tagObj) {
-        const name = obj?.constructor?.name ?? typeof obj;
+        const name = obj?.constructor?.name ?? (obj === null ? 'null' : typeof obj);
         throw new Error(`Tag not resolved for ${name} value`);
     }
     return tagObj;
@@ -1540,7 +1550,7 @@ function stringifyProps(node, tagObj, { anchors, doc }) {
         anchors.add(anchor);
         props.push(`&${anchor}`);
     }
-    const tag = node.tag ? node.tag : tagObj.default ? null : tagObj.tag;
+    const tag = node.tag ?? (tagObj.default ? null : tagObj.tag);
     if (tag)
         props.push(doc.directives.tagString(tag));
     return props.join(' ');
@@ -1566,8 +1576,7 @@ function stringify$2(item, ctx, onComment, onChompKeep) {
     const node = isNode(item)
         ? item
         : ctx.doc.createNode(item, { onTagObj: o => (tagObj = o) });
-    if (!tagObj)
-        tagObj = getTagObject(ctx.doc.schema.tags, node);
+    tagObj ?? (tagObj = getTagObject(ctx.doc.schema.tags, node));
     const props = stringifyProps(node, tagObj, ctx);
     if (props.length > 0)
         ctx.indentAtStart = (ctx.indentAtStart ?? 0) + props.length + 1;
@@ -1826,6 +1835,7 @@ function addPairToJSMap(ctx, map, { key, value }) {
 function stringifyKey(key, jsKey, ctx) {
     if (jsKey === null)
         return '';
+    // eslint-disable-next-line @typescript-eslint/no-base-to-string
     if (typeof jsKey !== 'object')
         return String(jsKey);
     if (isNode(key) && ctx?.doc) {
@@ -2530,8 +2540,7 @@ const binary = {
         else {
             throw new Error('This environment does not support writing binary tags; either Buffer or btoa is required');
         }
-        if (!type)
-            type = Scalar.BLOCK_LITERAL;
+        type ?? (type = Scalar.BLOCK_LITERAL);
         if (type !== Scalar.QUOTE_DOUBLE) {
             const lineWidth = Math.max(ctx.options.lineWidth - ctx.indent.length, ctx.options.minContentWidth);
             const n = Math.ceil(str.length / lineWidth);
@@ -3667,8 +3676,7 @@ function resolveProps(tokens, { flow, indicator, next, offset, onError, parentIn
                 if (token.source.endsWith(':'))
                     onError(token.offset + token.source.length - 1, 'BAD_ALIAS', 'Anchor ending in : is ambiguous', true);
                 anchor = token;
-                if (start === null)
-                    start = token.offset;
+                start ?? (start = token.offset);
                 atNewline = false;
                 hasSpace = false;
                 reqSpace = true;
@@ -3677,8 +3685,7 @@ function resolveProps(tokens, { flow, indicator, next, offset, onError, parentIn
                 if (tag)
                     onError(token, 'MULTIPLE_TAGS', 'A node can have at most one tag');
                 tag = token;
-                if (start === null)
-                    start = token.offset;
+                start ?? (start = token.offset);
                 atNewline = false;
                 hasSpace = false;
                 reqSpace = true;
@@ -4754,8 +4761,7 @@ function findScalarTagByTest({ atKey, directives, schema }, value, token, onErro
 
 function emptyScalarPosition(offset, before, pos) {
     if (before) {
-        if (pos === null)
-            pos = before.length;
+        pos ?? (pos = before.length);
         for (let i = pos - 1; i >= 0; --i) {
             let st = before[i];
             switch (st.type) {
diff --git a/package-lock.json b/package-lock.json
index 844bc4d..d21d1f9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -10145,14 +10145,14 @@
       "dev": true
     },
     "node_modules/yaml": {
-      "version": "2.7.1",
-      "resolved": "https://registry.npmjs.org/yaml/-/yaml-2.7.1.tgz",
-      "integrity": "sha512-10ULxpnOCQXxJvBgxsn9ptjq6uviG/htZKk9veJGhlqn3w/DxQ631zFF+nlQXLwmImeS5amR2dl2U8sg6U9jsQ==",
+      "version": "2.8.0",
+      "resolved": "https://registry.npmjs.org/yaml/-/yaml-2.8.0.tgz",
+      "integrity": "sha512-4lLa/EcQCB0cJkyts+FpIRx5G/llPxfP6VQU5KByHEhLxY3IJCH0f0Hy1MHI8sClTvsIb8qwRJ6R/ZdlDJ/leQ==",
       "bin": {
         "yaml": "bin.mjs"
       },
       "engines": {
-        "node": ">= 14"
+        "node": ">= 14.6"
       }
     },
     "node_modules/yargs": {