diff --git a/lib/gui/modules/child-writer.js b/lib/gui/modules/child-writer.js
deleted file mode 100644
index 7463f933..00000000
--- a/lib/gui/modules/child-writer.js
+++ /dev/null
@@ -1,244 +0,0 @@
-/*
- * Copyright 2017 balena.io
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *    http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-'use strict'
-
-const Bluebird = require('bluebird')
-const _ = require('lodash')
-const ipc = require('node-ipc')
-const sdk = require('etcher-sdk')
-// eslint-disable-next-line node/no-missing-require
-const EXIT_CODES = require('../../shared/exit-codes')
-// eslint-disable-next-line node/no-missing-require
-const errors = require('../../shared/errors')
-
-ipc.config.id = process.env.IPC_CLIENT_ID
-ipc.config.socketRoot = process.env.IPC_SOCKET_ROOT
-
-// NOTE: Ensure this isn't disabled, as it will cause
-// the stdout maxBuffer size to be exceeded when flashing
-ipc.config.silent = true
-
-// > If set to 0, the client will NOT try to reconnect.
-// See https://github.com/RIAEvangelist/node-ipc/
-//
-// The purpose behind this change is for this process
-// to emit a "disconnect" event as soon as the GUI
-// process is closed, so we can kill this process as well.
-ipc.config.stopRetrying = 0
-
-const DISCONNECT_DELAY = 100
-const IPC_SERVER_ID = process.env.IPC_SERVER_ID
-
-/**
- * @summary Send a log debug message to the IPC server
- * @function
- * @private
- *
- * @param {String} message - message
- *
- * @example
- * log('Hello world!')
- */
-const log = (message) => {
-  ipc.of[IPC_SERVER_ID].emit('log', message)
-}
-
-/**
- * @summary Terminate the child writer process
- * @function
- * @private
- *
- * @param {Number} [code=0] - exit code
- *
- * @example
- * terminate(1)
- */
-const terminate = (code) => {
-  ipc.disconnect(IPC_SERVER_ID)
-  process.nextTick(() => {
-    process.exit(code || EXIT_CODES.SUCCESS)
-  })
-}
-
-/**
- * @summary Handle a child writer error
- * @function
- * @private
- *
- * @param {Error} error - error
- *
- * @example
- * handleError(new Error('Something bad happened!'))
- */
-const handleError = async (error) => {
-  ipc.of[IPC_SERVER_ID].emit('error', errors.toJSON(error))
-  await Bluebird.delay(DISCONNECT_DELAY)
-  terminate(EXIT_CODES.GENERAL_ERROR)
-}
-
-/**
- * @summary writes the source to the destinations and valiates the writes
- * @param {SourceDestination} source - source
- * @param {SourceDestination[]} destinations - destinations
- * @param {Boolean} verify - whether to validate the writes or not
- * @param {Boolean} trim - whether to trim ext partitions before writing
- * @param {Function} onProgress - function to call on progress
- * @param {Function} onFail - function to call on fail
- * @returns {Promise<{ bytesWritten, devices, errors} >}
- *
- * @example
- * writeAndValidate(source, destinations, verify, onProgress, onFail, onFinish, onError)
- */
-const writeAndValidate = async (source, destinations, verify, trim, onProgress, onFail) => {
-  let innerSource = await source.getInnerSource()
-  if (trim && (await innerSource.canRead())) {
-    innerSource = new sdk.sourceDestination.ConfiguredSource(
-      innerSource,
-      trim,
-
-      // Create stream from file-disk (not source stream)
-      true
-    )
-  }
-  const { failures, bytesWritten } = await sdk.multiWrite.pipeSourceToDestinations(
-    innerSource,
-    destinations,
-    onFail,
-    onProgress,
-    verify
-  )
-  const result = {
-    bytesWritten,
-    devices: {
-      failed: failures.size,
-      successful: destinations.length - failures.size
-    },
-    errors: []
-  }
-  for (const [ destination, error ] of failures) {
-    error.device = destination.drive.device
-    result.errors.push(error)
-  }
-  return result
-}
-
-ipc.connectTo(IPC_SERVER_ID, () => {
-  process.once('uncaughtException', handleError)
-
-  // Gracefully exit on the following cases. If the parent
-  // process detects that child exit successfully but
-  // no flashing information is available, then it will
-  // assume that the child died halfway through.
-
-  process.once('SIGINT', () => {
-    terminate(EXIT_CODES.SUCCESS)
-  })
-
-  process.once('SIGTERM', () => {
-    terminate(EXIT_CODES.SUCCESS)
-  })
-
-  // The IPC server failed. Abort.
-  ipc.of[IPC_SERVER_ID].on('error', () => {
-    terminate(EXIT_CODES.SUCCESS)
-  })
-
-  // The IPC server was disconnected. Abort.
-  ipc.of[IPC_SERVER_ID].on('disconnect', () => {
-    terminate(EXIT_CODES.SUCCESS)
-  })
-
-  ipc.of[IPC_SERVER_ID].on('write', async (options) => {
-    /**
-     * @summary Progress handler
-     * @param {Object} state - progress state
-     * @example
-     * writer.on('progress', onProgress)
-     */
-    const onProgress = (state) => {
-      ipc.of[IPC_SERVER_ID].emit('state', state)
-    }
-
-    let exitCode = EXIT_CODES.SUCCESS
-
-    /**
-     * @summary Abort handler
-     * @example
-     * writer.on('abort', onAbort)
-     */
-    const onAbort = async () => {
-      log('Abort')
-      ipc.of[IPC_SERVER_ID].emit('abort')
-      await Bluebird.delay(DISCONNECT_DELAY)
-      terminate(exitCode)
-    }
-
-    ipc.of[IPC_SERVER_ID].on('cancel', onAbort)
-
-    /**
-     * @summary Failure handler (non-fatal errors)
-     * @param {SourceDestination} destination - destination
-     * @param {Error} error - error
-     * @example
-     * writer.on('fail', onFail)
-     */
-    const onFail = (destination, error) => {
-      ipc.of[IPC_SERVER_ID].emit('fail', {
-        // TODO: device should be destination
-        device: destination.drive,
-        error: errors.toJSON(error)
-      })
-    }
-
-    const destinations = _.map(options.destinations, 'device')
-    log(`Image: ${options.imagePath}`)
-    log(`Devices: ${destinations.join(', ')}`)
-    log(`Umount on success: ${options.unmountOnSuccess}`)
-    log(`Validate on success: ${options.validateWriteOnSuccess}`)
-    log(`Trim: ${options.trim}`)
-    const dests = _.map(options.destinations, (destination) => {
-      return new sdk.sourceDestination.BlockDevice(destination, options.unmountOnSuccess)
-    })
-    const source = new sdk.sourceDestination.File(options.imagePath, sdk.sourceDestination.File.OpenFlags.Read)
-    try {
-      const results = await writeAndValidate(
-        source,
-        dests,
-        options.validateWriteOnSuccess,
-        options.trim,
-        onProgress,
-        onFail
-      )
-      log(`Finish: ${results.bytesWritten}`)
-      results.errors = _.map(results.errors, (error) => {
-        return errors.toJSON(error)
-      })
-      ipc.of[IPC_SERVER_ID].emit('done', { results })
-      await Bluebird.delay(DISCONNECT_DELAY)
-      terminate(exitCode)
-    } catch (error) {
-      log(`Error: ${error.message}`)
-      exitCode = EXIT_CODES.GENERAL_ERROR
-      ipc.of[IPC_SERVER_ID].emit('error', errors.toJSON(error))
-    }
-  })
-
-  ipc.of[IPC_SERVER_ID].on('connect', () => {
-    log(`Successfully connected to IPC server: ${IPC_SERVER_ID}, socket root ${ipc.config.socketRoot}`)
-    ipc.of[IPC_SERVER_ID].emit('ready', {})
-  })
-})
diff --git a/lib/gui/modules/child-writer.ts b/lib/gui/modules/child-writer.ts
new file mode 100644
index 00000000..4d3c4413
--- /dev/null
+++ b/lib/gui/modules/child-writer.ts
@@ -0,0 +1,260 @@
+/*
+ * Copyright 2017 balena.io
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { delay } from 'bluebird';
+import { Drive as DrivelistDrive } from 'drivelist';
+import * as sdk from 'etcher-sdk';
+import * as _ from 'lodash';
+import * as ipc from 'node-ipc';
+
+import { toJSON } from '../../shared/errors';
+import { GENERAL_ERROR, SUCCESS } from '../../shared/exit-codes';
+
+ipc.config.id = process.env.IPC_CLIENT_ID as string;
+ipc.config.socketRoot = process.env.IPC_SOCKET_ROOT as string;
+
+// NOTE: Ensure this isn't disabled, as it will cause
+// the stdout maxBuffer size to be exceeded when flashing
+ipc.config.silent = true;
+
+// > If set to 0, the client will NOT try to reconnect.
+// See https://github.com/RIAEvangelist/node-ipc/
+//
+// The purpose behind this change is for this process
+// to emit a "disconnect" event as soon as the GUI
+// process is closed, so we can kill this process as well.
+// @ts-ignore (0 is a valid value for stopRetrying and is not the same as false)
+ipc.config.stopRetrying = 0;
+
+const DISCONNECT_DELAY = 100;
+const IPC_SERVER_ID = process.env.IPC_SERVER_ID as string;
+
+/**
+ * @summary Send a log debug message to the IPC server
+ */
+function log(message: string) {
+	ipc.of[IPC_SERVER_ID].emit('log', message);
+}
+
+/**
+ * @summary Terminate the child writer process
+ */
+function terminate(exitCode: number) {
+	ipc.disconnect(IPC_SERVER_ID);
+	process.nextTick(() => {
+		process.exit(exitCode || SUCCESS);
+	});
+}
+
+/**
+ * @summary Handle a child writer error
+ */
+async function handleError(error: Error) {
+	ipc.of[IPC_SERVER_ID].emit('error', toJSON(error));
+	await delay(DISCONNECT_DELAY);
+	terminate(GENERAL_ERROR);
+}
+
+interface WriteResult {
+	bytesWritten: number;
+	devices: {
+		failed: number;
+		successful: number;
+	};
+	errors: Array<Error & { device: string }>;
+}
+
+/**
+ * @summary writes the source to the destinations and valiates the writes
+ * @param {SourceDestination} source - source
+ * @param {SourceDestination[]} destinations - destinations
+ * @param {Boolean} verify - whether to validate the writes or not
+ * @param {Boolean} trim - whether to trim ext partitions before writing
+ * @param {Function} onProgress - function to call on progress
+ * @param {Function} onFail - function to call on fail
+ * @returns {Promise<{ bytesWritten, devices, errors} >}
+ */
+async function writeAndValidate(
+	source: sdk.sourceDestination.SourceDestination,
+	destinations: sdk.sourceDestination.BlockDevice[],
+	verify: boolean,
+	trim: boolean,
+	onProgress: sdk.multiWrite.OnProgressFunction,
+	onFail: sdk.multiWrite.OnFailFunction,
+): Promise<WriteResult> {
+	let innerSource: sdk.sourceDestination.SourceDestination = await source.getInnerSource();
+	if (trim && (await innerSource.canRead())) {
+		// @ts-ignore FIXME: ts thinks that SparseReadStream can't be assigned to SparseReadable (which it implements)
+		innerSource = new sdk.sourceDestination.ConfiguredSource(
+			innerSource,
+			trim,
+			// Create stream from file-disk (not source stream)
+			true,
+		);
+	}
+	const {
+		failures,
+		bytesWritten,
+	} = await sdk.multiWrite.pipeSourceToDestinations(
+		innerSource,
+		// @ts-ignore FIXME: ts thinks that BlockWriteStream can't be assigned to WritableStream (which it implements)
+		destinations,
+		onFail,
+		onProgress,
+		verify,
+	);
+	const result: WriteResult = {
+		bytesWritten,
+		devices: {
+			failed: failures.size,
+			successful: destinations.length - failures.size,
+		},
+		errors: [],
+	};
+	for (const [destination, error] of failures) {
+		(error as (Error & { device: string })).device = destination.drive.device;
+		result.errors.push(error);
+	}
+	return result;
+}
+
+interface WriteOptions {
+	imagePath: string;
+	destinations: DrivelistDrive[];
+	unmountOnSuccess: boolean;
+	validateWriteOnSuccess: boolean;
+	trim: boolean;
+}
+
+ipc.connectTo(IPC_SERVER_ID, () => {
+	process.once('uncaughtException', handleError);
+
+	// Gracefully exit on the following cases. If the parent
+	// process detects that child exit successfully but
+	// no flashing information is available, then it will
+	// assume that the child died halfway through.
+
+	process.once('SIGINT', () => {
+		terminate(SUCCESS);
+	});
+
+	process.once('SIGTERM', () => {
+		terminate(SUCCESS);
+	});
+
+	// The IPC server failed. Abort.
+	ipc.of[IPC_SERVER_ID].on('error', () => {
+		terminate(SUCCESS);
+	});
+
+	// The IPC server was disconnected. Abort.
+	ipc.of[IPC_SERVER_ID].on('disconnect', () => {
+		terminate(SUCCESS);
+	});
+
+	ipc.of[IPC_SERVER_ID].on('write', async (options: WriteOptions) => {
+		/**
+		 * @summary Progress handler
+		 * @param {Object} state - progress state
+		 * @example
+		 * writer.on('progress', onProgress)
+		 */
+		const onProgress = (state: sdk.multiWrite.MultiDestinationProgress) => {
+			ipc.of[IPC_SERVER_ID].emit('state', state);
+		};
+
+		let exitCode = SUCCESS;
+
+		/**
+		 * @summary Abort handler
+		 * @example
+		 * writer.on('abort', onAbort)
+		 */
+		const onAbort = async () => {
+			log('Abort');
+			ipc.of[IPC_SERVER_ID].emit('abort');
+			await delay(DISCONNECT_DELAY);
+			terminate(exitCode);
+		};
+
+		ipc.of[IPC_SERVER_ID].on('cancel', onAbort);
+
+		/**
+		 * @summary Failure handler (non-fatal errors)
+		 * @param {SourceDestination} destination - destination
+		 * @param {Error} error - error
+		 * @example
+		 * writer.on('fail', onFail)
+		 */
+		const onFail = (
+			destination: sdk.sourceDestination.BlockDevice,
+			error: Error,
+		) => {
+			ipc.of[IPC_SERVER_ID].emit('fail', {
+				// TODO: device should be destination
+				// @ts-ignore (destination.drive is private)
+				device: destination.drive,
+				error: toJSON(error),
+			});
+		};
+
+		const destinations = _.map(options.destinations, 'device');
+		log(`Image: ${options.imagePath}`);
+		log(`Devices: ${destinations.join(', ')}`);
+		log(`Umount on success: ${options.unmountOnSuccess}`);
+		log(`Validate on success: ${options.validateWriteOnSuccess}`);
+		log(`Trim: ${options.trim}`);
+		const dests = _.map(options.destinations, destination => {
+			return new sdk.sourceDestination.BlockDevice(
+				destination,
+				options.unmountOnSuccess,
+			);
+		});
+		const source = new sdk.sourceDestination.File(
+			options.imagePath,
+			sdk.sourceDestination.File.OpenFlags.Read,
+		);
+		try {
+			const results = await writeAndValidate(
+				// @ts-ignore FIXME: ts thinks that SparseWriteStream can't be assigned to SparseWritable (which it implements)
+				source,
+				dests,
+				options.validateWriteOnSuccess,
+				options.trim,
+				onProgress,
+				onFail,
+			);
+			log(`Finish: ${results.bytesWritten}`);
+			results.errors = _.map(results.errors, error => {
+				return toJSON(error);
+			});
+			ipc.of[IPC_SERVER_ID].emit('done', { results });
+			await delay(DISCONNECT_DELAY);
+			terminate(exitCode);
+		} catch (error) {
+			log(`Error: ${error.message}`);
+			exitCode = GENERAL_ERROR;
+			ipc.of[IPC_SERVER_ID].emit('error', toJSON(error));
+		}
+	});
+
+	ipc.of[IPC_SERVER_ID].on('connect', () => {
+		log(
+			`Successfully connected to IPC server: ${IPC_SERVER_ID}, socket root ${ipc.config.socketRoot}`,
+		);
+		ipc.of[IPC_SERVER_ID].emit('ready', {});
+	});
+});
diff --git a/lib/start.js b/lib/start.js
index 28c90d5d..668b54bc 100644
--- a/lib/start.js
+++ b/lib/start.js
@@ -24,6 +24,7 @@
 // or the entry point file (this file) manually as an argument.
 
 if (process.env.ELECTRON_RUN_AS_NODE) {
+  // eslint-disable-next-line node/no-missing-require
   require('./gui/modules/child-writer')
 } else {
   require('./gui/etcher')
diff --git a/npm-shrinkwrap.json b/npm-shrinkwrap.json
index f83b8d04..28f042f0 100644
--- a/npm-shrinkwrap.json
+++ b/npm-shrinkwrap.json
@@ -1215,6 +1215,15 @@
       "resolved": "https://registry.npmjs.org/@types/node/-/node-12.12.24.tgz",
       "integrity": "sha512-1Ciqv9pqwVtW6FsIUKSZNB82E5Cu1I2bBTj1xuIHXLe/1zYLl3956Nbhg2MzSYHVfl9/rmanjbQIb7LibfCnug=="
     },
+    "@types/node-ipc": {
+      "version": "9.1.2",
+      "resolved": "https://registry.npmjs.org/@types/node-ipc/-/node-ipc-9.1.2.tgz",
+      "integrity": "sha512-140YlGizUg2Dbbmypc97RZ2iaWOEdcwec6QPJ9C5AWy8H/Hus6co4MeEF2lRPmOTBY3GJu+Xaxyr4FfyE6Hjew==",
+      "dev": true,
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@types/normalize-package-data": {
       "version": "2.4.0",
       "resolved": "https://registry.npmjs.org/@types/normalize-package-data/-/normalize-package-data-2.4.0.tgz",
diff --git a/package.json b/package.json
index d2f1471e..60d94ce8 100644
--- a/package.json
+++ b/package.json
@@ -97,6 +97,7 @@
     "@types/bindings": "^1.3.0",
     "@types/mime-types": "^2.1.0",
     "@types/node": "^12.12.24",
+    "@types/node-ipc": "^9.1.2",
     "@types/react-dom": "^16.8.4",
     "@types/request": "^2.48.4",
     "@types/semver": "^6.2.0",
diff --git a/tests/gui/modules/child-writer.spec.js b/tests/gui/modules/child-writer.spec.js
index 3b5929ec..bccfec97 100644
--- a/tests/gui/modules/child-writer.spec.js
+++ b/tests/gui/modules/child-writer.spec.js
@@ -18,6 +18,7 @@
 
 const m = require('mochainon')
 const ipc = require('node-ipc')
+// eslint-disable-next-line node/no-missing-require
 require('../../../lib/gui/modules/child-writer')
 
 describe('Browser: childWriter', function () {