diff --git a/.changeset/selfish-fans-pump.md b/.changeset/selfish-fans-pump.md
new file mode 100644
index 00000000..c27a1225
--- /dev/null
+++ b/.changeset/selfish-fans-pump.md
@@ -0,0 +1,5 @@
+---
+"@terrazzo/parser": patch
+---
+
+Fix bug in alias resolution
diff --git a/.changeset/serious-wombats-invent.md b/.changeset/serious-wombats-invent.md
new file mode 100644
index 00000000..cd69cd5f
--- /dev/null
+++ b/.changeset/serious-wombats-invent.md
@@ -0,0 +1,5 @@
+---
+"@terrazzo/parser": patch
+---
+
+Fix type error with parser output
diff --git a/packages/parser/src/parse/alias.ts b/packages/parser/src/parse/alias.ts
index f2c992f3..87c527c9 100644
--- a/packages/parser/src/parse/alias.ts
+++ b/packages/parser/src/parse/alias.ts
@@ -130,7 +130,7 @@ export function applyAliases(
             const { id: aliasID, mode: aliasMode } = parseAlias(subvalue);
             const aliasToken = tokens[aliasOfID]!;
             const possibleTypes: string[] = expectedAliasTypes?.[property as keyof typeof expectedAliasTypes] || [];
-            if (!possibleTypes.includes(aliasToken.$type)) {
+            if (possibleTypes.length && !possibleTypes.includes(aliasToken.$type)) {
               const elementNode = ($valueNode as ArrayNode).elements[i]!.value;
               logger.error({
                 message: `Invalid alias: expected $type: "${possibleTypes.join('" or "')}", received $type: "${aliasToken.$type}".`,
diff --git a/packages/parser/src/parse/index.ts b/packages/parser/src/parse/index.ts
index bd4b5ef2..df3ebda4 100644
--- a/packages/parser/src/parse/index.ts
+++ b/packages/parser/src/parse/index.ts
@@ -3,11 +3,10 @@ import { type Token, type TokenNormalized, isTokenMatch, pluralize, splitID } fr
 import type ytm from 'yaml-to-momoa';
 import lintRunner from '../lint/index.js';
 import Logger from '../logger.js';
-import type { ConfigInit } from '../types.js';
+import type { ConfigInit, InputSource } from '../types.js';
 import { applyAliases } from './alias.js';
 import { getObjMembers, injectObjMembers, maybeJSONString, traverse } from './json.js';
 import normalize from './normalize.js';
-import type { ParseInput } from './types.js';
 import validate from './validate.js';
 
 export * from './validate.js';
@@ -31,12 +30,12 @@ export interface ParseOptions {
 
 export interface ParseResult {
   tokens: Record<string, TokenNormalized>;
-  sources: Record<string, ParseInput>;
+  sources: InputSource[];
 }
 
 /** Parse */
 export default async function parse(
-  input: ParseInput[],
+  input: Omit<InputSource, 'document'>[],
   {
     logger = new Logger(),
     skipLint = false,
@@ -48,7 +47,7 @@ export default async function parse(
   let tokens: Record<string, TokenNormalized> = {};
   // note: only keeps track of sources with locations on disk; in-memory sources are discarded
   // (it’s only for reporting line numbers, which doesn’t mean as much for dynamic sources)
-  const sources: Record<string, ParseInput> = {};
+  const sources: Record<string, InputSource> = {};
 
   if (!Array.isArray(input)) {
     logger.error({ group: 'parser', label: 'init', message: 'Input must be an array of input objects.' });
@@ -86,6 +85,7 @@ export default async function parse(
       sources[input[i]!.filename!.protocol === 'file:' ? input[i]!.filename!.href : input[i]!.filename!.href] = {
         filename: input[i]!.filename,
         src: result.src,
+        document: result.document,
       };
     }
   }
@@ -170,7 +170,7 @@ export default async function parse(
 
   return {
     tokens,
-    sources,
+    sources: Object.values(sources),
   };
 }
 
@@ -449,5 +449,9 @@ async function parseSingle(
     timing: performance.now() - normalizeStart,
   });
 
-  return { tokens, document, src };
+  return {
+    tokens,
+    document,
+    src,
+  };
 }
diff --git a/packages/parser/src/parse/types.ts b/packages/parser/src/parse/types.ts
deleted file mode 100644
index fb2fd6eb..00000000
--- a/packages/parser/src/parse/types.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-export interface ParseInput {
-  /** Source filename (if read from disk) */
-  filename?: URL;
-  /** JSON/YAML string, or JSON-serializable object (if already in memory) */
-  src: string | object;
-}
diff --git a/packages/plugin-css/test/cli.test.ts b/packages/plugin-css/test/cli.test.ts
index 96ac6dad..fd90cf49 100644
--- a/packages/plugin-css/test/cli.test.ts
+++ b/packages/plugin-css/test/cli.test.ts
@@ -67,7 +67,7 @@ describe('tz build', () => {
     it('outDir', async () => {
       const cwd = new URL('./fixtures/cli-config-outdir/', import.meta.url);
       await execa('node', [cmd, 'build'], { cwd });
-      expect(fs.readFileSync(new URL('./styles/out/actual.css', cwd), 'utf8')).toMatchFileSnapshot(
+      await expect(fs.readFileSync(new URL('./styles/out/actual.css', cwd), 'utf8')).toMatchFileSnapshot(
         fileURLToPath(new URL('./styles/out/want.css', cwd)),
       );
     });
diff --git a/packages/plugin-css/test/js.test.ts b/packages/plugin-css/test/js.test.ts
index b9d9914a..1f383260 100644
--- a/packages/plugin-css/test/js.test.ts
+++ b/packages/plugin-css/test/js.test.ts
@@ -62,7 +62,7 @@ describe('Node.js API', () => {
           config,
         });
         const result = await build(tokens, { sources, config });
-        expect(result.outputFiles.find((f) => f.filename === output)?.contents).toMatchFileSnapshot(
+        await expect(result.outputFiles.find((f) => f.filename === output)?.contents).toMatchFileSnapshot(
           fileURLToPath(new URL('./want.css', cwd)),
         );
       },
@@ -93,12 +93,16 @@ describe('Node.js API', () => {
       { cwd },
     );
     const tokensJSON = new URL('./tokens.json', cwd);
-    const { tokens, sources } = await parse([{ filename: tokensJSON, src: fs.readFileSync(tokensJSON, 'utf8') }], {
-      config,
-    });
-    const result = await build(tokens, { sources, config });
-    expect(result.outputFiles.find((f) => f.filename === output)?.contents).toMatchFileSnapshot(
-      fileURLToPath(new URL('./want.css', cwd)),
-    );
+    try {
+      const { tokens, sources } = await parse([{ filename: tokensJSON, src: fs.readFileSync(tokensJSON, 'utf8') }], {
+        config,
+      });
+      const result = await build(tokens, { sources, config });
+      await expect(result.outputFiles.find((f) => f.filename === output)?.contents).toMatchFileSnapshot(
+        fileURLToPath(new URL('./want.css', cwd)),
+      );
+    } catch (err) {
+      console.error(err);
+    }
   });
 });
diff --git a/packages/plugin-js/test/index.test.ts b/packages/plugin-js/test/index.test.ts
index 668fb2a0..f33c35b0 100644
--- a/packages/plugin-js/test/index.test.ts
+++ b/packages/plugin-js/test/index.test.ts
@@ -24,10 +24,10 @@ describe('@terrazzo/plugin-js', () => {
         config,
       });
       const result = await build(tokens, { sources, config });
-      expect(result.outputFiles.find((f) => f.filename === filename)?.contents).toMatchFileSnapshot(
+      await expect(result.outputFiles.find((f) => f.filename === filename)?.contents).toMatchFileSnapshot(
         fileURLToPath(new URL('./want.js', cwd)),
       );
-      expect(
+      await expect(
         result.outputFiles.find((f) => f.filename === filename.replace(/\.js$/, '.d.ts'))?.contents,
       ).toMatchFileSnapshot(fileURLToPath(new URL('./want.d.ts', cwd)));
 
diff --git a/packages/plugin-sass/test/index.test.ts b/packages/plugin-sass/test/index.test.ts
index cba304a8..9067ada2 100644
--- a/packages/plugin-sass/test/index.test.ts
+++ b/packages/plugin-sass/test/index.test.ts
@@ -30,7 +30,7 @@ describe('@terrazzo/plugin-scss', () => {
       config,
     });
     const result = await build(tokens, { sources, config });
-    expect(result.outputFiles.find((f) => f.filename === filename)?.contents).toMatchFileSnapshot(
+    await expect(result.outputFiles.find((f) => f.filename === filename)?.contents).toMatchFileSnapshot(
       fileURLToPath(new URL('./want.scss', cwd)),
     );
   });
diff --git a/packages/plugin-swift/test/index.test.ts b/packages/plugin-swift/test/index.test.ts
index 670eee53..10a6cdff 100644
--- a/packages/plugin-swift/test/index.test.ts
+++ b/packages/plugin-swift/test/index.test.ts
@@ -24,7 +24,7 @@ describe('@terrazzo/plugin-swift', () => {
     });
     const result = await build(tokens, { config, sources });
     for (const { filename, contents } of result.outputFiles) {
-      expect(contents).toMatchFileSnapshot(fileURLToPath(new URL(filename, cwd)));
+      await expect(contents).toMatchFileSnapshot(fileURLToPath(new URL(filename, cwd)));
     }
   });
 });
diff --git a/packages/plugin-tailwind/test/index.test.ts b/packages/plugin-tailwind/test/index.test.ts
index 7d5d3e25..b84ed7ff 100644
--- a/packages/plugin-tailwind/test/index.test.ts
+++ b/packages/plugin-tailwind/test/index.test.ts
@@ -60,20 +60,16 @@ describe('@cobalt-ui/plugin-tailwind', () => {
         const config = defineConfig(
           {
             outDir: './cjs/',
-            plugins: [
-              pluginTailwind({
-                ...baseConfig,
-                filename: './actual.js',
-                format: 'cjs',
-              }),
-            ],
+            plugins: [pluginTailwind({ ...baseConfig, filename: './actual.js', format: 'cjs' })],
           },
           { cwd },
         );
-        const { tokens, ast } = await parse(fs.readFileSync(new URL('../tokens.yaml', cwd), 'utf8'));
-        await build(tokens, { ast, config });
+        const { tokens, sources } = await parse([{ src: fs.readFileSync(new URL('../tokens.yaml', cwd), 'utf8') }], {
+          config,
+        });
+        await build(tokens, { sources, config });
 
-        expect(fs.readFileSync(new URL('./actual.js', cwd), 'utf8')).toMatchFileSnapshot(
+        await expect(fs.readFileSync(new URL('./actual.js', cwd), 'utf8')).toMatchFileSnapshot(
           fileURLToPath(new URL('./want.js', cwd)),
         );
       });
@@ -83,20 +79,16 @@ describe('@cobalt-ui/plugin-tailwind', () => {
         const config = defineConfig(
           {
             outDir: './cjs/',
-            plugins: [
-              pluginTailwind({
-                ...baseConfig,
-                filename: './actual.js',
-                format: 'esm',
-              }),
-            ],
+            plugins: [pluginTailwind({ ...baseConfig, filename: './actual.js', format: 'esm' })],
           },
           { cwd },
         );
-        const { tokens, ast } = await parse(fs.readFileSync(new URL('../tokens.yaml', cwd), 'utf8'));
-        await build(tokens, { ast, config });
+        const { tokens, sources } = await parse([{ src: fs.readFileSync(new URL('../tokens.yaml', cwd), 'utf8') }], {
+          config,
+        });
+        await build(tokens, { sources, config });
 
-        expect(fs.readFileSync(new URL('./actual.js', cwd), 'utf8')).toMatchFileSnapshot(
+        await expect(fs.readFileSync(new URL('./actual.js', cwd), 'utf8')).toMatchFileSnapshot(
           fileURLToPath(new URL('./want.js', cwd)),
         );
       });