diff --git a/packages/3-targets/6-adapters/postgres/src/core/sql-renderer.ts b/packages/3-targets/6-adapters/postgres/src/core/sql-renderer.ts
index 24579d30b616..26709ec56bc4 100644
--- a/packages/3-targets/6-adapters/postgres/src/core/sql-renderer.ts
+++ b/packages/3-targets/6-adapters/postgres/src/core/sql-renderer.ts
@@ -196,7 +196,17 @@ function renderLimitOffset(
   pim: ParamIndexMap,
 ): string {
   if (value === undefined) return '';
-  if (typeof value === 'number') return `${keyword} ${value}`;
+  if (typeof value === 'number') {
+    // NaN/±Infinity stringify into SQL identifiers (`LIMIT NaN`) and crash the engine.
+    if (!Number.isFinite(value)) {
+      throw adapterError(
+        'RUNTIME.AST_INVALID',
+        `${keyword} requires a finite number, got ${String(value)}`,
+        { meta: { node: 'select', clause: keyword } },
+      );
+    }
+    return `${keyword} ${value}`;
+  }
   return `${keyword} ${renderExpr(value, contract, pim)}`;
 }
 
diff --git a/packages/3-targets/6-adapters/postgres/test/adapter-errors.test.ts b/packages/3-targets/6-adapters/postgres/test/adapter-errors.test.ts
index 06daac81f43c..6e3cc8234afe 100644
--- a/packages/3-targets/6-adapters/postgres/test/adapter-errors.test.ts
+++ b/packages/3-targets/6-adapters/postgres/test/adapter-errors.test.ts
@@ -142,6 +142,22 @@ describe('adapter-postgres structured error codes', () => {
     );
   });
 
+  it('raises RUNTIME.AST_INVALID for a non-finite LIMIT or OFFSET', () => {
+    const base = () =>
+      SelectAst.from(TableSource.named('user', undefined, 'public')).withProjection([
+        ProjectionItem.of('id', ColumnRef.of('user', 'id')),
+      ]);
+    for (const ast of [
+      base().withLimit(Number.NaN),
+      base().withLimit(Number.POSITIVE_INFINITY),
+      base().withOffset(Number.NaN),
+    ]) {
+      expect(structuredCodeOf(() => renderLoweredSql(ast, contract, codecLookup))).toBe(
+        'RUNTIME.AST_INVALID',
+      );
+    }
+  });
+
   it('raises RUNTIME.AST_INVALID for an INSERT with zero rows', () => {
     const ast = InsertAst.into(TableSource.named('user', undefined, 'public')).withRows([]);
     expect(structuredCodeOf(() => renderLoweredSql(ast, contract, codecLookup))).toBe(
diff --git a/packages/3-targets/6-adapters/sqlite/src/core/adapter.ts b/packages/3-targets/6-adapters/sqlite/src/core/adapter.ts
index 81f2cb537219..7bb31e975afa 100644
--- a/packages/3-targets/6-adapters/sqlite/src/core/adapter.ts
+++ b/packages/3-targets/6-adapters/sqlite/src/core/adapter.ts
@@ -228,7 +228,17 @@ function renderLimitOffset(
   ctx: SqliteRenderContext,
 ): string {
   if (value === undefined) return '';
-  if (typeof value === 'number') return `${keyword} ${value}`;
+  if (typeof value === 'number') {
+    // NaN/±Infinity stringify into SQL identifiers (`LIMIT NaN`) and crash the engine.
+    if (!Number.isFinite(value)) {
+      throw structuredError(
+        'RUNTIME.AST_INVALID',
+        `${keyword} requires a finite number, got ${String(value)}`,
+        { meta: { node: 'select', clause: keyword } },
+      );
+    }
+    return `${keyword} ${value}`;
+  }
   return `${keyword} ${renderExpr(value, ctx)}`;
 }
 
diff --git a/packages/3-targets/6-adapters/sqlite/test/adapter.test.ts b/packages/3-targets/6-adapters/sqlite/test/adapter.test.ts
index 9024b0144409..9667e319692c 100644
--- a/packages/3-targets/6-adapters/sqlite/test/adapter.test.ts
+++ b/packages/3-targets/6-adapters/sqlite/test/adapter.test.ts
@@ -156,6 +156,21 @@ describe('SQLite adapter', () => {
       );
     });
 
+    it('throws RUNTIME.AST_INVALID for non-finite LIMIT / OFFSET', () => {
+      const base = () =>
+        SelectAst.from(TableSource.named('user')).withProjection([
+          ProjectionItem.of('id', ColumnRef.of('user', 'id')),
+        ]);
+      for (const ast of [
+        base().withLimit(Number.NaN),
+        base().withLimit(Number.POSITIVE_INFINITY),
+        base().withOffset(Number.NaN),
+        base().withLimit(1).withOffset(Number.NEGATIVE_INFINITY),
+      ]) {
+        expect(() => adapter.lower(ast, { contract })).toThrow(/requires a finite number/);
+      }
+    });
+
     it('renders DISTINCT', () => {
       const ast = SelectAst.from(TableSource.named('user'))
         .withProjection([ProjectionItem.of('email', ColumnRef.of('user', 'email'))])
diff --git a/packages/3-targets/6-adapters/sqlite/test/structured-errors.test.ts b/packages/3-targets/6-adapters/sqlite/test/structured-errors.test.ts
index 0fe5db9b350f..3201d0ecba5e 100644
--- a/packages/3-targets/6-adapters/sqlite/test/structured-errors.test.ts
+++ b/packages/3-targets/6-adapters/sqlite/test/structured-errors.test.ts
@@ -99,6 +99,22 @@ describe('structured error codes', () => {
     });
   });
 
+  it('RUNTIME.AST_INVALID on a non-finite LIMIT', () => {
+    const err = catchError(() =>
+      runtimeAdapter.lower(
+        SelectAst.from(TableSource.named('user'))
+          .withProjection([ProjectionItem.of('id', LiteralExpr.of(1))])
+          .withLimit(Number.NaN),
+        { contract },
+      ),
+    );
+    expect(isStructuredError(err)).toBe(true);
+    expect(err).toMatchObject({
+      code: 'RUNTIME.AST_INVALID',
+      meta: { node: 'select', clause: 'LIMIT' },
+    });
+  });
+
   it('RUNTIME.AST_UNSUPPORTED on DEFAULT as an INSERT value', () => {
     const ast = InsertAst.into(TableSource.named('user')).withRows([
       { email: new DefaultValueExpr() },