diff --git a/src/bom2table.js b/src/bom2table.js
deleted file mode 100644
index 6f7cd68..0000000
--- a/src/bom2table.js
+++ /dev/null
@@ -1,166 +0,0 @@
-/* eslint-disable array-callback-return */
-// Modules
-const beautify = require('js-beautify').html;
-const csv = require('csvtojson');
-
-// Configuration
-// Which components should we remove from the BOM?
-const rejectedParts = [
-  'TP1',
-  'TP2',
-  'TP3',
-  'G',
-  'U$1',
-  'S1',
-  'J1',
-  'J2',
-  'JP1',
-  'JP2',
-  'V',
-  'I',
-  'O',
-  'T1',
-  'T2',
-  'T3',
-  'INPUT',
-];
-
-// Return false if the Part value of the object passed in is in the list to remove
-function isJunk(element) {
-  return !rejectedParts.includes(element.Part);
-}
-
-function getPartType(partName) {
-  // console.log(partName.Part);
-  if (partName.Part.match(/^C\d/) != null) {
-    return 'C';
-    // eslint-disable-next-line no-else-return
-  } else if (partName.Part.match(/^R\d/) != null) {
-    return 'R';
-  }
-  return 'Q';
-}
-
-function getJSONParts(allParts) {
-  const jsonParts = {};
-  const C = {};
-  const R = {};
-  const Q = {};
-
-  allParts.map((partEntry) => {
-    switch (getPartType(partEntry)) {
-      case 'C':
-        C[partEntry.Part] = partEntry.Value;
-        break;
-      case 'R':
-        R[partEntry.Part] = partEntry.Value;
-        break;
-      default:
-        Q[partEntry.Part] = partEntry.Value;
-    }
-  });
-
-  jsonParts.C = C;
-  jsonParts.R = R;
-  jsonParts.Q = Q;
-
-  return jsonParts;
-}
-
-// Format the HTML nicely and output to a pre code block
-function displayMarkup() {
-  const tableCode = document.querySelector('table').outerHTML;
-  const markup = document.getElementById('markup');
-  markup.innerText = beautify(tableCode);
-}
-
-// Table functions
-function clearTable() {
-  document.querySelector('table').innerHTML = '';
-}
-
-function generateTableHead(table, data) {
-  const thead = table.createTHead();
-  const row = thead.insertRow();
-  // Populate Header row
-  data.map((key) => {
-    const th = document.createElement('th');
-    const text = document.createTextNode(key);
-    th.appendChild(text);
-    row.appendChild(th);
-  });
-}
-
-function generateTableBody(table, data) {
-  data.map((component) => {
-    const row = table.insertRow();
-    // Insert Part Name
-    const partName = row.insertCell();
-    const partNameText = document.createTextNode(component.Part);
-    partName.appendChild(partNameText);
-    // Insert Part Value
-    const partVal = row.insertCell();
-    const partValText = document.createTextNode(component.Value);
-    partVal.appendChild(partValText);
-  });
-}
-
-function makeTable(csvString) {
-  csv({
-    delimiter: ';',
-    includeColumns: /(Part|Value)/,
-    ignoreEmpty: true,
-  })
-    .fromString(csvString)
-    .then((jsonObj) => {
-      // Create array containing only relevant parts
-      const parts = jsonObj.filter(isJunk);
-      console.log(parts);
-      const table = document.querySelector('table');
-      const headerData = Object.keys(parts[0]);
-      generateTableBody(table, parts);
-      generateTableHead(table, headerData);
-      displayMarkup();
-    })
-    .catch((e) => {
-      console.error(e);
-    });
-}
-
-// Create a JSON object for Contentful
-function makeJSON(csvString) {
-  csv({
-    delimiter: ';',
-    includeColumns: /(Part|Value)/,
-    ignoreEmpty: true,
-  })
-    .fromString(csvString)
-    .then((res) => {
-      const object = res.filter(isJunk);
-
-      const parts = getJSONParts(object);
-
-      document.getElementById('jsonObject').innerText = JSON.stringify(
-        parts,
-        null,
-        2,
-      );
-    })
-    .catch((e) => {
-      console.error(e);
-    });
-}
-
-function handleFiles() {
-  const csvFilePath = this.files[0];
-  const reader = new FileReader();
-  reader.readAsText(csvFilePath);
-  reader.onload = () => {
-    clearTable();
-    makeTable(reader.result);
-    makeJSON(reader.result);
-  };
-}
-
-const csvPicker = document.getElementById('csvFile');
-csvPicker.addEventListener('change', handleFiles, false);
diff --git a/src/bom2table.ts b/src/bom2table.ts
new file mode 100644
index 0000000..c1d4486
--- /dev/null
+++ b/src/bom2table.ts
@@ -0,0 +1,163 @@
+/* eslint-disable @typescript-eslint/no-non-null-assertion */
+/* eslint-disable array-callback-return */
+// Modules
+import { html as beautify } from 'js-beautify';
+import csv from 'csvtojson';
+import { Converter } from 'csvtojson/v2/Converter';
+
+// Configuration
+// Which components should we remove from the BOM?
+const rejectedParts = [
+  'TP1',
+  'TP2',
+  'TP3',
+  'G',
+  'U$1',
+  'S1',
+  'J1',
+  'J2',
+  'JP1',
+  'JP2',
+  'V',
+  'I',
+  'O',
+  'T1',
+  'T2',
+  'T3',
+  'INPUT',
+];
+
+// Return false if the Part value of the object passed in is in the list to remove
+function isJunk(element: part) {
+  return !rejectedParts.includes(element.Part);
+}
+
+function getPartType(component: part) {
+  // console.log(partName.Part);
+  if (component.Part.match(/^C\d/) != null) {
+    return 'C';
+    // eslint-disable-next-line no-else-return
+  } else if (component.Part.match(/^R\d/) != null) {
+    return 'R';
+  }
+  return 'Q';
+}
+
+function getJSONParts(allParts: part[]) {
+  const jsonParts: structuredParts = {
+    C: {},
+    R: {},
+    Q: {},
+  };
+
+  allParts.map((partEntry: part) => {
+    switch (getPartType(partEntry)) {
+      case 'C':
+        jsonParts.C[partEntry.Part] = partEntry.Value;
+        break;
+      case 'R':
+        jsonParts.R[partEntry.Part] = partEntry.Value;
+        break;
+      default:
+        jsonParts.Q[partEntry.Part] = partEntry.Value;
+    }
+  });
+  return jsonParts;
+}
+
+// Format the HTML nicely and output to a pre code block
+function displayMarkup() {
+  const tableCode = document.querySelector('table')!.outerHTML;
+  const markup = document.getElementById('markup') as HTMLElement;
+  markup.innerText = beautify(tableCode);
+}
+
+// Table functions
+function clearTable() {
+  document.querySelector('table')!.innerHTML = '';
+}
+
+function generateTableHead(table: HTMLTableElement, data: Array<string>) {
+  const thead = table.createTHead();
+  const row = thead.insertRow();
+  // Populate Header row
+  data.map((key) => {
+    const th = document.createElement('th');
+    const text = document.createTextNode(key);
+    th.appendChild(text);
+    row.appendChild(th);
+  });
+}
+
+function generateTableBody(table: HTMLTableElement, data: part[]) {
+  data.map((component) => {
+    const row = table.insertRow();
+    // Insert Part Name
+    const partName = row.insertCell();
+    const partNameText = document.createTextNode(component.Part);
+    partName.appendChild(partNameText);
+    // Insert Part Value
+    const partVal = row.insertCell();
+    const partValText = document.createTextNode(component.Value);
+    partVal.appendChild(partValText);
+  });
+}
+
+async function makeTable(csvString: string) {
+
+  const converter: Converter = csv({
+    delimiter: ';',
+    includeColumns: /(Part|Value)/,
+    ignoreEmpty: true,
+  })
+
+  const jsonArray = await converter.fromString(csvString);
+  // Filter out unwanted parts
+  const parts = jsonArray.filter(isJunk);
+  // Build table
+  const table = document.querySelector('table') as HTMLTableElement;
+  const headerData = Object.keys(parts[0]);
+  generateTableBody(table, parts);
+  generateTableHead(table, headerData);
+  displayMarkup();
+}
+
+// Create a JSON object for Contentful
+function makeJSON(csvString: string) {
+  csv({
+    delimiter: ';',
+    includeColumns: /(Part|Value)/,
+    ignoreEmpty: true,
+  })
+    .fromString(csvString)
+    .then((res) => {
+      const object = res.filter(isJunk);
+
+      const parts = getJSONParts(object);
+
+      document.getElementById('jsonObject')!.innerText = JSON.stringify(
+        parts,
+        null,
+        2,
+      );
+    });
+}
+
+const csvPicker = document.getElementById('csvFile') as HTMLInputElement;
+// csvPicker?.addEventListener('change', handleFiles, false);
+csvPicker.onchange = function handleFiles(event: Event) {
+  // const csvFile = event.target.files[0];
+  const target = event.target as HTMLInputElement;
+  const csvFile: File = (target.files as FileList)[0];
+  const reader = new FileReader();
+  reader.readAsText(csvFile);
+  reader.onload = () => {
+    if (reader.result == null) {
+      throw new Error('Something went wrong.');
+    }
+    const csvString = reader.result.toString();
+    clearTable();
+    makeTable(csvString);
+    makeJSON(csvString);
+  };
+}
diff --git a/src/boms2table.d.ts b/src/boms2table.d.ts
index 94b7a4b..2f3b8cf 100644
--- a/src/boms2table.d.ts
+++ b/src/boms2table.d.ts
@@ -2,3 +2,15 @@ interface part {
   Part: string,
   Value: string,
 }
+
+interface structuredParts {
+  C: {
+    [key: string]: string
+  },
+  R: {
+    [key: string]: string
+  },
+  Q: {
+    [key: string]: string
+  }
+}
\ No newline at end of file