diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 45d25427..06d6385d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,7 +7,7 @@ on:
     branches: [master]
 
 jobs:
-  build:
+  build-and-test:
     runs-on: ubuntu-latest
 
     steps:
diff --git a/src/components/Modals/Interlace/index.tsx b/src/components/Modals/Interlace/index.tsx
index 67c85428..ee2e2fbc 100644
--- a/src/components/Modals/Interlace/index.tsx
+++ b/src/components/Modals/Interlace/index.tsx
@@ -45,20 +45,16 @@ export const InterlaceModal = ({
   const { fetchRegions } = useRegions();
 
   const currentMask = regionMetadata.region.getMask().toBin();
+  // Represents the first active bit in the bitmap.
   const oneStart = currentMask.indexOf('1');
+  // Represents the last active bit in the bitmap.
   const oneEnd = currentMask.lastIndexOf('1');
   const activeBits = oneEnd - oneStart + 1;
 
   const [working, setWorking] = useState(false);
   const [position, setPosition] = useState(oneStart);
 
-  const generateMask = (position: number): string => {
-    const mask = Array(COREMASK_BIT_LEN).fill('0');
-    for (let i = oneStart; i <= position; ++i) mask[i] = '1';
-    return mask.join('');
-  };
-
-  const newMask = generateMask(position);
+  const newMask = CoreMask.fromChunk(oneStart, position + 1).toBin();
 
   const onInterlace = async () => {
     if (!api || !activeAccount || !activeSigner) return;
diff --git a/src/pages/purchase/index.tsx b/src/pages/purchase.tsx
similarity index 99%
rename from src/pages/purchase/index.tsx
rename to src/pages/purchase.tsx
index 4c295dc9..accdc9c6 100644
--- a/src/pages/purchase/index.tsx
+++ b/src/pages/purchase.tsx
@@ -29,7 +29,7 @@ import {
   getSaleEndInBlocks,
   getSaleProgress,
   getSaleStartInBlocks,
-} from '../../utils/sale/util';
+} from '../utils/sale/utils';
 
 const Purchase = () => {
   const theme = useTheme();
diff --git a/src/utils/sale/util.test.ts b/src/utils/sale/utils.test.ts
similarity index 99%
rename from src/utils/sale/util.test.ts
rename to src/utils/sale/utils.test.ts
index 0e869f67..1c256c60 100644
--- a/src/utils/sale/util.test.ts
+++ b/src/utils/sale/utils.test.ts
@@ -6,7 +6,7 @@ import {
   getSaleEndInBlocks,
   getSaleProgress,
   getSaleStartInBlocks,
-} from './util';
+} from './utils';
 
 describe('Purchase page', () => {
   const mockSaleInfo: SaleInfo = {
diff --git a/src/utils/sale/util.ts b/src/utils/sale/utils.ts
similarity index 100%
rename from src/utils/sale/util.ts
rename to src/utils/sale/utils.ts