diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 74ed5d6..de0cca9 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -131,7 +131,8 @@ jobs:
 
       - name: Publish package
         run: |
-          cp README.md app/
+          chmod u+x scripts/npm-publish.sh
+          ./scripts/npm-publish.sh
           cd app
           npm publish
         env:
diff --git a/README.md b/README.md
index 186530a..cac376f 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,12 @@ It also asks users to key in the file download URL of a remote PAGASA 10-Day wea
 
 > _**INFO:** When installing the package using `npm i ph-municipalities`, the default data source is inside `/data/day1.xlsx`. All source codes and files are also inside the **ph-municipalities** root directory._
 
+### Architecture Diagram
+
+![ph-municipalities-arch](/docs/diagrams/ph-municipalities-arch-90.png)
+
+###  Dataset Output
+
 Extracted municipalities are written in JSON files following the format:
 
 ```
@@ -65,6 +71,7 @@ The following dependencies are used for this project. Feel free to use other dep
   - [`npm run minify:all`](#npm-run-minifyall)
   - [`npm run lint`](#npm-run-lint)
   - [`npm run lint:fix`](#npm-run-lintfix)
+  - [`npm test`](#npm-test)
 - [Class Usage](#class-usage)
   - [Load and Parse a Local Excel File](#load-and-parse-a-local-excel-file)
   - [Download and Parse a Remote Excel File](#download-and-parse-a-remote-excel-file)
@@ -220,6 +227,10 @@ Lint JavaScript source codes.
 
 Fix JavaScript lint errors.
 
+### `npm test`
+
+Run tests defined in the `/app/__tests__` directory.
+
 ## Class Usage
 
 Below are example usages of the `ExcelFile` class, run from the **/app/src/examples** directory. Check out the `/app/src/examples/sample_usage.js` file for more examples.
diff --git a/app/package-lock.json b/app/package-lock.json
index 99370e0..3e0b6c6 100644
--- a/app/package-lock.json
+++ b/app/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "ph-municipalities",
-  "version": "1.3.3",
+  "version": "1.3.4",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "ph-municipalities",
-      "version": "1.3.3",
+      "version": "1.3.4",
       "license": "ISC",
       "dependencies": {
         "dotenv": "^16.0.1",
diff --git a/app/package.json b/app/package.json
index 81ab17a..50a54c6 100644
--- a/app/package.json
+++ b/app/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ph-municipalities",
-  "version": "1.3.3",
+  "version": "1.3.4",
   "description": "List and write the `municipalities` of Philippines provinces or regions into JSON files",
   "main": "index.js",
   "engines": {
diff --git a/docs/diagrams/ph-municipalities-arch-90.png b/docs/diagrams/ph-municipalities-arch-90.png
new file mode 100644
index 0000000..b40d835
Binary files /dev/null and b/docs/diagrams/ph-municipalities-arch-90.png differ
diff --git a/docs/diagrams/ph-municipalities-arch.drawio b/docs/diagrams/ph-municipalities-arch.drawio
new file mode 100644
index 0000000..5a234a7
--- /dev/null
+++ b/docs/diagrams/ph-municipalities-arch.drawio
@@ -0,0 +1,133 @@
+<mxfile host="Electron" modified="2024-08-28T02:39:18.762Z" agent="Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) draw.io/22.0.3 Chrome/114.0.5735.289 Electron/25.8.4 Safari/537.36" etag="v7skEjIrMClVe-O8wROi" version="22.0.3" type="device">
+  <diagram name="Page-1" id="PT_rIEPRiHDDqEcKwNWF">
+    <mxGraphModel dx="2518" dy="974" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="850" pageHeight="1100" math="0" shadow="0">
+      <root>
+        <mxCell id="0" />
+        <mxCell id="1" parent="0" />
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-98" value="" style="rounded=0;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+          <mxGeometry x="-650" y="305" width="200" height="326" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-60" value="" style="shape=cylinder3;whiteSpace=wrap;html=1;boundedLbl=1;backgroundOutline=1;size=15;" vertex="1" parent="1">
+          <mxGeometry x="-200" y="128" width="140" height="195" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-73" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-1" target="N0Y9xDM0efUduAB5_r4A-63">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-126" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;entryX=0.75;entryY=0;entryDx=0;entryDy=0;dashed=1;endArrow=none;endFill=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-1" target="N0Y9xDM0efUduAB5_r4A-98">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-1" value="ExcelFile / ExcelFactory&lt;br&gt;(class)" style="rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;" vertex="1" parent="1">
+          <mxGeometry x="-545" y="195" width="150" height="60" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-4" value="PAGASA 10-day Excel file&lt;br&gt;(local cache)" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-180" y="173" width="100" height="60" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-5" value="PAGASA 10-day Excel file&lt;br&gt;(remote)" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-180" y="243" width="100" height="60" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-10" value="" style="rounded=1;whiteSpace=wrap;html=1;" vertex="1" parent="1">
+          <mxGeometry x="-570" y="20" width="200" height="50" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-25" value="PAGASA seasonal settings&lt;br&gt;(region - province names)" style="html=1;verticalLabelPosition=middle;align=left;labelBackgroundColor=#ffffff;verticalAlign=middle;strokeWidth=2;strokeColor=#0080F0;shadow=0;dashed=0;shape=mxgraph.ios7.icons.settings;labelPosition=right;spacingLeft=6;" vertex="1" parent="1">
+          <mxGeometry x="-560" y="30" width="30" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-62" value="load()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-338" y="210.5" width="70" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-74" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=0.5;entryY=1;entryDx=0;entryDy=0;startArrow=classic;startFill=1;dashed=1;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-63" target="N0Y9xDM0efUduAB5_r4A-10">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-78" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;entryX=0.5;entryY=0;entryDx=0;entryDy=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-63" target="N0Y9xDM0efUduAB5_r4A-62">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-63" value="init()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-505" y="118" width="70" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-76" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=0;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;dashed=1;startArrow=classic;startFill=1;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-62" target="N0Y9xDM0efUduAB5_r4A-60">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-77" value="Data Sources" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontStyle=1" vertex="1" parent="1">
+          <mxGeometry x="-175" y="133" width="90" height="20" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-80" value="" style="shape=cylinder3;whiteSpace=wrap;html=1;boundedLbl=1;backgroundOutline=1;size=15;" vertex="1" parent="1">
+          <mxGeometry x="-373" y="323" width="140" height="227" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-81" value="Stored Data" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontStyle=1" vertex="1" parent="1">
+          <mxGeometry x="-349" y="329" width="90" height="20" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-83" value="Processed province / municipality&lt;br&gt;names" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-352" y="370" width="100" height="60" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-84" value="Raw Excel data&lt;br&gt;(json)&lt;br&gt;" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-352" y="440" width="100" height="40" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-85" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=0.5;entryY=0;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-62" target="N0Y9xDM0efUduAB5_r4A-80">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-87" value="listRegions()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-630" y="348" width="160" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-88" value="listAllProvinces()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-630" y="398" width="160" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-116" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-89" target="N0Y9xDM0efUduAB5_r4A-108">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-89" value="listMunicipalities()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-630" y="448" width="160" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-90" value="writeMuniicipalities()" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-630" y="498" width="160" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-91" value="get()*" style="shape=process;whiteSpace=wrap;html=1;backgroundOutline=1;" vertex="1" parent="1">
+          <mxGeometry x="-630" y="548" width="160" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-92" value="PAGASA seasonal settings" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-352" y="490" width="100" height="40" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-96" value="Class Methods" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;fontStyle=1" vertex="1" parent="1">
+          <mxGeometry x="-610" y="312" width="110" height="30" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-99" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=0;entryY=0;entryDx=0;entryDy=64.25;entryPerimeter=0;dashed=1;startArrow=classic;startFill=1;exitX=1;exitY=0.25;exitDx=0;exitDy=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-98" target="N0Y9xDM0efUduAB5_r4A-80">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-106" value="province list" style="strokeWidth=2;html=1;shape=mxgraph.flowchart.direct_data;whiteSpace=wrap;spacingRight=20;" vertex="1" parent="1">
+          <mxGeometry x="-830" y="402.5" width="120" height="43" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-107" value="region list" style="strokeWidth=2;html=1;shape=mxgraph.flowchart.direct_data;whiteSpace=wrap;spacingRight=20;" vertex="1" parent="1">
+          <mxGeometry x="-830" y="342" width="120" height="43" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-108" value="municipality list" style="strokeWidth=2;html=1;shape=mxgraph.flowchart.direct_data;whiteSpace=wrap;spacingRight=20;" vertex="1" parent="1">
+          <mxGeometry x="-830" y="467.5" width="120" height="43" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-109" value="municipality list&lt;br&gt;JSON" style="whiteSpace=wrap;html=1;shape=mxgraph.basic.document" vertex="1" parent="1">
+          <mxGeometry x="-815" y="532" width="90" height="60" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-111" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=1;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-87" target="N0Y9xDM0efUduAB5_r4A-107">
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+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-112" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;entryX=1;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-88" target="N0Y9xDM0efUduAB5_r4A-106">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-118" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;entryX=1;entryY=0.5;entryDx=0;entryDy=0;entryPerimeter=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-90" target="N0Y9xDM0efUduAB5_r4A-109">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-119" value="(other class methods)" style="text;html=1;strokeColor=none;fillColor=none;align=center;verticalAlign=middle;whiteSpace=wrap;rounded=0;" vertex="1" parent="1">
+          <mxGeometry x="-615" y="601" width="130" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-134" style="edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;entryX=0;entryY=0.75;entryDx=0;entryDy=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-121" target="N0Y9xDM0efUduAB5_r4A-1">
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+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-121" value="NPM script&lt;br&gt;list:province" style="shape=parallelogram;perimeter=parallelogramPerimeter;whiteSpace=wrap;html=1;fixedSize=1;fillColor=#f5f5f5;fontColor=#333333;strokeColor=#666666;" vertex="1" parent="1">
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+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-133" style="edgeStyle=orthogonalEdgeStyle;rounded=1;orthogonalLoop=1;jettySize=auto;html=1;entryX=0;entryY=0.25;entryDx=0;entryDy=0;" edge="1" parent="1" source="N0Y9xDM0efUduAB5_r4A-130" target="N0Y9xDM0efUduAB5_r4A-1">
+          <mxGeometry relative="1" as="geometry" />
+        </mxCell>
+        <mxCell id="N0Y9xDM0efUduAB5_r4A-130" value="NPM script&lt;br&gt;list:region" style="shape=parallelogram;perimeter=parallelogramPerimeter;whiteSpace=wrap;html=1;fixedSize=1;fillColor=#f5f5f5;strokeColor=#666666;fontColor=#333333;" vertex="1" parent="1">
+          <mxGeometry x="-730" y="128" width="130" height="52" as="geometry" />
+        </mxCell>
+      </root>
+    </mxGraphModel>
+  </diagram>
+</mxfile>
diff --git a/scripts/npm-publish.sh b/scripts/npm-publish.sh
new file mode 100644
index 0000000..fa08807
--- /dev/null
+++ b/scripts/npm-publish.sh
@@ -0,0 +1,4 @@
+#!/bin/bash
+
+sed "s|/docs/diagrams/||g" README.md > app/README.md
+cp docs/diagrams/ph-municipalities-arch-90.png app/