diff --git a/src/parse.ts b/src/parse.ts
index 091c22c..62fb5a9 100644
--- a/src/parse.ts
+++ b/src/parse.ts
@@ -19,6 +19,8 @@ const singleQuoteReg = /'(?:\\[\s\w"'\\`]|[^\n\r'\\])*?'/g;
 
 const doubleQuoteReg = /"(?:\\[\s\w"'\\`]|[^\n\r"\\])*?"/g;
 
+const lineTerminatorReg = /(?:\r\n|[\n\r\u2028\u2029])/g;
+
 /** Escape special regular expression characters inside a string */
 
 function escapeRegExp(string: string) {
@@ -109,7 +111,9 @@ export function parse(this: Eta, str: string): Array<AstObject> {
   );
 
   const parseCloseReg = new RegExp(
-    "'|\"|`|\\/\\*|(\\s*(-|_)?" + escapeRegExp(config.tags[1]) + ")",
+    "'|\"|`|\\/\\*|(\\s*(-|_)?" +
+      escapeRegExp(config.tags[1]) +
+      ")|\\/\\/",
     "g",
   );
 
@@ -161,6 +165,14 @@ export function parse(this: Eta, str: string): Array<AstObject> {
             ParseErr("unclosed comment", str, closeTag.index);
           }
           parseCloseReg.lastIndex = commentCloseInd;
+        } else if (char === "//") {
+          lineTerminatorReg.lastIndex = parseCloseReg.lastIndex;
+          const match = lineTerminatorReg.exec(str);
+          if (match) {
+            parseCloseReg.lastIndex = match.index + match[0].length;
+          } else {
+            parseCloseReg.lastIndex = str.length;
+          }
         } else if (char === "'") {
           singleQuoteReg.lastIndex = closeTag.index;
 
diff --git a/test/parse.spec.ts b/test/parse.spec.ts
index 2b8f757..4de8e01 100644
--- a/test/parse.spec.ts
+++ b/test/parse.spec.ts
@@ -34,6 +34,22 @@ describe("parse test", () => {
     ]);
   });
 
+  it("works with unpaired apostrophe in single-line comment", () => {
+    const buff = eta.parse("hi <% // comment with unpaired apostrophe' \n %>");
+    expect(buff).toEqual([
+      "hi ",
+      { val: "// comment with unpaired apostrophe' \n", t: "e" },
+    ]);
+  });
+
+  it("works with unpaired apostrophe in multiline comment", () => {
+    const buff = eta.parse("hi <% /* comment with unpaired apostrophe' */ %>");
+    expect(buff).toEqual([
+      "hi ",
+      { val: "/* comment with unpaired apostrophe' */", t: "e" },
+    ]);
+  });
+
   it("parses with simple template literal", () => {
     // biome-ignore lint/suspicious/noTemplateCurlyInString: intentional
     const buff = eta.parse("hi <%= `template %> ${value}` %>");
@@ -114,4 +130,32 @@ describe("parse test", () => {
   <%= /* %>
       ^`);
   });
+
+  it("handles alternative closing tags properly, rather than confusing them with comments", () => {
+    const originalEta = new Eta({ tags: ["{{", "//"] });
+    const buff = originalEta.parse("{{= it.x//");
+    expect(buff).toEqual([{ val: "it.x", t: "i" }]);
+    const originalEta2 = new Eta({ tags: ["{{", "//}}"] });
+    const buff2 = originalEta2.parse("{{= it.x//}}");
+    expect(buff2).toEqual([{ val: "it.x", t: "i" }]);
+  });
+
+  it("handles various line termination characters in single-line comments", () => {
+    const cases = ["\r", "\r\n", "\u2028", "\u2029", "\n"];
+    for (const terminator of cases) {
+      const buff = eta.parse(`hi <% // comment ending with terminator${terminator} %>`);
+      expect(buff).toEqual([
+        "hi ",
+        { val: `// comment ending with terminator${terminator}`, t: "e" },
+      ]);
+    }
+  });
+
+  it("handles a sequence looking like close tag inside single line comment", () => {
+    const buff = eta.parse("hi <% // comment %> with close tag\n %>");
+    expect(buff).toEqual([
+      "hi ",
+      { val: "// comment %> with close tag\n", t: "e" },
+    ]);
+  });
 });