diff --git a/packages/cosmo/src/main/scala/cosmo/Expr.scala b/packages/cosmo/src/main/scala/cosmo/Expr.scala
index 8234ee0..d57164c 100644
--- a/packages/cosmo/src/main/scala/cosmo/Expr.scala
+++ b/packages/cosmo/src/main/scala/cosmo/Expr.scala
@@ -46,6 +46,7 @@ class ExprEnv(val env: Env) {
 
   def expr(node: s.Node): Expr = {
     node match {
+      case s.Err(msg) => err(msg)
       // literals
       case s.TodoLit        => TodoLit.e
       case s.BoolLit(value) => Bool(value).e
diff --git a/packages/cosmo/src/main/scala/cosmo/Parser.scala b/packages/cosmo/src/main/scala/cosmo/Parser.scala
index b8b2ab7..ae67490 100644
--- a/packages/cosmo/src/main/scala/cosmo/Parser.scala
+++ b/packages/cosmo/src/main/scala/cosmo/Parser.scala
@@ -7,6 +7,10 @@ import fastparse._, fastparse.ScalaWhitespace._
 import cosmo.syntax._
 import cosmo.syntax.NodeParse._
 
+implicit class SoftErr[$: P](p: => P[Unit]) {
+  def err(msg: String): P[Unit] = p.map(_ => Err(msg))
+}
+
 object Parser {
   // Entry point
   def root[$: P]: P[Block] =
@@ -30,7 +34,8 @@ object Parser {
   def idCont[$: P] = P(letter | digit | "_")
 
   def delimStr[T, $: P](d: String, body: => P[T]) = d ~~/ delimStrCont(d, body)
-  def delimStrCont[T, $: P](d: String, body: => P[T]) = (!d ~~ body).repX.! ~~ d
+  def delimStrCont[T, $: P](d: String, body: => P[T]) =
+    (!End ~ !d ~~ body).repX.! ~~ (d | End.err("Unclosed string"))
   def shortStr[$: P] = P(shortStr0.map(unescapeStr))
   def shortStr0[$: P] = delimStr("\"", strEscape)
   def longStr[$: P] = P("\"".repX(3).!./.flatMapX(longStr0))
@@ -53,7 +58,7 @@ object Parser {
     P(longChars("\"$", delim).repX.! ~~/ tmplExpr)
 
   def longChars[$: P](mores: String, delim: String): P[Unit] =
-    P(litCharsWhile(mores) | !delim ~~ "\"".repX)
+    !End ~ P(litCharsWhile(mores) | !delim ~~ "\"".repX)
   def litCharsWhile[$: P](mores: String) = P(CharsWhile(!mores.contains(_)))
   def escapeseq[$: P]: P[Unit] = P("\\" ~ AnyChar)
   def tmplExpr[$: P]: P[Option[(Node, Option[String])]] =
diff --git a/packages/cosmo/src/main/scala/cosmo/Syntax.scala b/packages/cosmo/src/main/scala/cosmo/Syntax.scala
index 912a6e4..18b9048 100644
--- a/packages/cosmo/src/main/scala/cosmo/Syntax.scala
+++ b/packages/cosmo/src/main/scala/cosmo/Syntax.scala
@@ -17,6 +17,7 @@ sealed abstract class Node {
   def children: Iterator[Node] = this match {
     case Decorate(lhs, rhs)  => Iterator(lhs, rhs)
     case Semi(semi)          => semi.iterator
+    case Err(msg)            => Iterator.empty
     case Ident(name)         => Iterator.empty
     case BoolLit(value)      => Iterator.empty
     case IntLit(value)       => Iterator.empty
@@ -78,6 +79,7 @@ final case class Semi(semi: No) extends Node
 final case class Decorate(lhs: Node, rhs: Node) extends Node
 
 // Kind: Literals
+final case class Err(msg: String) extends Node
 // Just panic on problematic impls
 object TodoLit extends Node
 // Identifier
diff --git a/packages/cosmo/src/main/scala/cosmo/SyntaxSerialization.scala b/packages/cosmo/src/main/scala/cosmo/SyntaxSerialization.scala
index ce57939..fb21449 100644
--- a/packages/cosmo/src/main/scala/cosmo/SyntaxSerialization.scala
+++ b/packages/cosmo/src/main/scala/cosmo/SyntaxSerialization.scala
@@ -49,6 +49,7 @@ private def j(node: NodeKinds, buf: StringBuilder): Unit = {
       j(rhs, buf)
       buf.append("}")
     case Ident(name)    => buf.append(s""" "ident", "name": "$name"}""")
+    case Err(msg)       => buf.append(s""" "err", "msg": "$msg"}""")
     case BoolLit(value) => buf.append(s""" "bool", "value": $value}""")
     case IntLit(value)  => buf.append(s""" "int", "value": "$value"}""")
     case FloatLit(value) =>
diff --git a/packages/cosmo/src/test/scala/cosmo/SampleTests.scala b/packages/cosmo/src/test/scala/cosmo/SampleTests.scala
index 05aa11b..68c5723 100644
--- a/packages/cosmo/src/test/scala/cosmo/SampleTests.scala
+++ b/packages/cosmo/src/test/scala/cosmo/SampleTests.scala
@@ -44,9 +44,12 @@ class SampleTest extends munit.FunSuite:
   test("Syntax/lambda.syntax") {
     runTestOnFile("samples/Syntax/lambda.syntax.cos")
   }
-  test("Syntax/try-catch.syntax".only) {
+  test("Syntax/try-catch.syntax") {
     runTestOnFile("samples/Syntax/try-catch.syntax.cos")
   }
+  test("Syntax/errs/tmplLit01".only) {
+    runTestOnFile("samples/Syntax/errs/tmplLit01.cos-ast")
+  }
   test("Syntax/tmplLit.syntax") {
     runTestOnFile("samples/Syntax/tmplLit.syntax.cos")
   }
diff --git a/samples/Syntax/errs/tmplLit01.cos-ast b/samples/Syntax/errs/tmplLit01.cos-ast
new file mode 100644
index 0000000..beaf269
--- /dev/null
+++ b/samples/Syntax/errs/tmplLit01.cos-ast
@@ -0,0 +1,3 @@
+
+"""
+terminate by EOF