diff --git a/src/__mocks__/glob.ts b/src/__mocks__/glob.ts
index 30855f1b..66140a35 100644
--- a/src/__mocks__/glob.ts
+++ b/src/__mocks__/glob.ts
@@ -17,9 +17,10 @@ module.exports = (
     const paths = mockGlobs[glob];
 
     if (!paths) {
-      return callback(new Error(`Invalid glob: ${glob}`), null);
+      callback(new Error(`Invalid glob: ${glob}`), null);
+      return;
     }
 
-    return callback(null, paths);
+    callback(null, paths);
   });
 };
diff --git a/src/__mocks__/path.ts b/src/__mocks__/path.ts
index 9974f859..60941c07 100644
--- a/src/__mocks__/path.ts
+++ b/src/__mocks__/path.ts
@@ -7,19 +7,17 @@ const resolve = (...paths: string[]) => {
   let path = '';
 
   for (const cur of paths) {
-    path = !path ? normalize(cur) : _path.join(path, normalize(cur));
+    path = path ? _path.join(path, normalize(cur)) : normalize(cur);
   }
 
   if (path.startsWith(projectDir)) {
     path = _path.join('/root/project', path.substr(projectDir.length));
   } else if (path.startsWith('/') && !path.startsWith('/root')) {
     path = _path.join('/root/', path.substr(1));
-  } else {
-    if (path.startsWith('./')) {
-      path = _path.join('/root/project/', path.substr(2));
-    } else if (!path.startsWith('/')) {
-      path = _path.join('/root/project/', path);
-    }
+  } else if (path.startsWith('./')) {
+    path = _path.join('/root/project/', path.substr(2));
+  } else if (!path.startsWith('/')) {
+    path = _path.join('/root/project/', path);
   }
 
   return normalize(path);
@@ -31,7 +29,7 @@ const relative = (a: string, b: string) =>
 const join = (...segments: string[]): string => {
   const trimmed: string[] = [];
 
-  segments.forEach((current, i) => {
+  for (let [i, current] of segments.entries()) {
     const isFirst = i === 0;
     const isLast = i === segments.length - 1;
 
@@ -44,7 +42,7 @@ const join = (...segments: string[]): string => {
     }
 
     trimmed.push(current);
-  });
+  }
 
   return trimmed.join('/');
 };
diff --git a/src/cli/config-loader.ts b/src/cli/config-loader.ts
index cb3273dd..c68f43c4 100644
--- a/src/cli/config-loader.ts
+++ b/src/cli/config-loader.ts
@@ -1,5 +1,6 @@
 import { readFile } from 'fs/promises';
 import { join } from 'path';
+import process from 'process';
 import { checkPath } from '../utils/fs-async';
 
 export const DEFAULT_FILEPATHS = [
@@ -11,17 +12,17 @@ export const DEFAULT_FILEPATHS = [
   'fantasticonrc.js'
 ];
 
-const attemptLoading = async (filepath: string): Promise<any | void> => {
+const attemptLoading = async (filepath: string) => {
   const fileExists = await checkPath(filepath, 'file');
   if (fileExists) {
     try {
       return require(join(process.cwd(), filepath));
-    } catch (err) {}
+    } catch {}
 
     try {
       const content = await readFile(filepath, 'utf8');
       return JSON.parse(content);
-    } catch (err) {}
+    } catch {}
 
     throw new Error(`Failed parsing configuration at '${filepath}'`);
   }
diff --git a/src/cli/index.ts b/src/cli/index.ts
index 054cac9a..3c74f417 100644
--- a/src/cli/index.ts
+++ b/src/cli/index.ts
@@ -1,16 +1,13 @@
+import process from 'process';
 import commander from 'commander';
 import { FontAssetType, OtherAssetType } from '../types/misc';
-import { loadConfig, DEFAULT_FILEPATHS } from './config-loader';
 import { DEFAULT_OPTIONS } from '../constants';
 import { generateFonts } from '../core/runner';
 import { removeUndefined } from '../utils/validation';
+import { loadConfig, DEFAULT_FILEPATHS } from './config-loader';
 import { getLogger } from './logger';
-
-const {
-  bin,
-  name: packageName,
-  version
-} = require('../../package.json') as any;
+// eslint-disable-next-line @typescript-eslint/no-var-requires
+const { bin, name: packageName, version } = require('../../package.json');
 
 const getCommandName = () => (bin && Object.keys(bin)[0]) || packageName;
 
@@ -37,11 +34,9 @@ const printList = (available: { [key: string]: string }, defaults: string[]) =>
   ).join(', ')})`;
 
 const printDefaultValue = (value: any) => {
-  let printVal = String(value);
+  const printVal = String(value);
 
-  if (typeof value === 'undefined') {
-    return '';
-  }
+  if (value === undefined) return '';
 
   return ` (default: ${printVal})`;
 };
@@ -137,6 +132,7 @@ const buildOptions = async (cmd: commander.Command, loadedConfig = {}) => {
   };
 };
 
-const run = async (options: any) => await generateFonts(options, true);
+const run = async (options: any) => generateFonts(options, true);
 
+// eslint-disable-next-line @typescript-eslint/no-floating-promises
 cli();
diff --git a/src/cli/logger.ts b/src/cli/logger.ts
index 3de00393..85b51465 100644
--- a/src/cli/logger.ts
+++ b/src/cli/logger.ts
@@ -24,6 +24,7 @@ export const getLogger = (debug = false, silent = false) => ({
     this.log(picocolor.yellow('Generating font kit...'));
 
     if (!loadedConfigPath) return;
+
     this.log(
       picocolor.green(
         `${figures.tick} Using configuration file: ${picocolor.green(
diff --git a/src/constants.ts b/src/constants.ts
index 811c4b70..a789d02a 100644
--- a/src/constants.ts
+++ b/src/constants.ts
@@ -1,6 +1,6 @@
 import { resolve } from 'path';
-import { RunnerOptions } from './types/runner';
 import { FontAssetType, OtherAssetType } from './types/misc';
+import { RunnerOptions } from './types/runner';
 import { getIconId } from './utils/icon-id';
 
 export const TEMPLATES_DIR = resolve(__dirname, '../templates');
@@ -26,7 +26,7 @@ export const DEFAULT_OPTIONS: Omit<RunnerOptions, 'inputDir' | 'outputDir'> = {
   tag: 'i',
   prefix: 'icon',
   fontsUrl: undefined,
-  getIconId: getIconId
+  getIconId
 };
 
 export const DEFAULT_START_CODEPOINT = 0xf101;
diff --git a/src/core/__tests__/config-parser.ts b/src/core/__tests__/config-parser.ts
index c59a61c0..3cbebb68 100644
--- a/src/core/__tests__/config-parser.ts
+++ b/src/core/__tests__/config-parser.ts
@@ -38,19 +38,19 @@ const mockConfig = {
 };
 
 const testError = async (options: object, key: string, message: string) =>
-  expect(() => parseConfig({ ...mockConfig, ...options })).rejects.toThrow(
-    `Invalid option ${key}: ${message}`
-  );
+  expect(async () =>
+    parseConfig({ ...mockConfig, ...options })
+  ).rejects.toThrow(`Invalid option ${key}: ${message}`);
 
-const testParsed = async (key: string, input: any, output: any) =>
-  expect((await parseConfig({ ...mockConfig, [key]: input }))[key]).toEqual(
-    output
-  );
+const testParsed = async (key: string, input: any, output: any) => {
+  const config = await parseConfig({ ...mockConfig, [key]: input });
+  expect(config[key]).toEqual(output);
+};
 
 describe('Config parser', () => {
   beforeEach(() => {
     checkPathMock.mockClear();
-    checkPathMock.mockImplementation(() => Promise.resolve(true));
+    checkPathMock.mockImplementation(async () => true);
   });
 
   test('returns correctly parsed input when valid', async () => {
@@ -93,11 +93,11 @@ describe('Config parser', () => {
   });
 
   test('correctly validates existance of input and output paths', async () => {
-    checkPathMock.mockImplementationOnce(() => Promise.resolve(false));
+    checkPathMock.mockImplementationOnce(async () => false);
 
     await testError({ inputDir: 'foo' }, 'inputDir', 'foo is not a directory');
 
-    checkPathMock.mockImplementation(val => Promise.resolve(val !== 'bar'));
+    checkPathMock.mockImplementation(async val => val !== 'bar');
 
     await testError(
       { outputDir: 'bar' },
@@ -107,7 +107,7 @@ describe('Config parser', () => {
   });
 
   test('throws expected error when passing an unrecognised option', async () => {
-    await expect(() =>
+    await expect(async () =>
       parseConfig({ ...mockConfig, foo: 'bar' })
     ).rejects.toThrow("The option 'foo' is not recognised");
   });
diff --git a/src/core/__tests__/runner.ts b/src/core/__tests__/runner.ts
index a19288dc..45732802 100644
--- a/src/core/__tests__/runner.ts
+++ b/src/core/__tests__/runner.ts
@@ -16,9 +16,9 @@ jest.mock('../../constants', () => ({
 }));
 
 jest.mock('../../generators', () => ({
-  generateAssets: jest.fn(options =>
-    Promise.resolve({ mockGenerated: { assets: {}, options } })
-  )
+  generateAssets: jest.fn(async options => ({
+    mockGenerated: { assets: {}, options }
+  }))
 }));
 
 jest.mock('../../generators/generator-options', () => ({
@@ -26,8 +26,8 @@ jest.mock('../../generators/generator-options', () => ({
 }));
 
 jest.mock('../../utils/assets', () => ({
-  writeAssets: jest.fn(() => Promise.resolve([{ mock: 'writeResult' }])),
-  loadAssets: jest.fn(() => Promise.resolve({ mock: 'assets' }))
+  writeAssets: jest.fn(async () => [{ mock: 'writeResult' }]),
+  loadAssets: jest.fn(async () => ({ mock: 'assets' }))
 }));
 
 jest.mock('../config-parser', () => ({
@@ -82,7 +82,7 @@ describe('Runner', () => {
   test('`generateFonts` throws error if `outputDir` is not given and `mustWrite` is `true`', async () => {
     const optionsIn = { inputDir: 'foo' } as any;
 
-    await expect(() => generateFonts(optionsIn, true)).rejects.toThrow(
+    await expect(async () => generateFonts(optionsIn, true)).rejects.toThrow(
       'You must specify an output directory'
     );
   });
@@ -90,7 +90,7 @@ describe('Runner', () => {
   test('`generateFonts` throws error if `inputDir` is not given', async () => {
     const optionsIn = {} as any;
 
-    await expect(() => generateFonts(optionsIn)).rejects.toThrow(
+    await expect(async () => generateFonts(optionsIn)).rejects.toThrow(
       'You must specify an input directory'
     );
   });
diff --git a/src/core/config-parser.ts b/src/core/config-parser.ts
index e44d1a6a..df06fb24 100644
--- a/src/core/config-parser.ts
+++ b/src/core/config-parser.ts
@@ -55,8 +55,8 @@ export const parseConfig = async (input: object = {}) => {
       for (const fn of validators) {
         val = await fn(val, val);
       }
-    } catch (err) {
-      throw new Error(`Invalid option ${key}: ${err.message}`);
+    } catch (error) {
+      throw new Error(`Invalid option ${key}: ${error.message}`);
     }
 
     out[key] = val;
diff --git a/src/core/runner.ts b/src/core/runner.ts
index d5152937..cbc96c6f 100644
--- a/src/core/runner.ts
+++ b/src/core/runner.ts
@@ -9,8 +9,8 @@ import {
 import { CodepointsMap } from '../utils/codepoints';
 import { getGeneratorOptions } from '../generators/generator-options';
 import { GeneratedAssets } from '../generators/generate-assets';
-import { parseConfig } from './config-parser';
 import { generateAssets } from '../generators';
+import { parseConfig } from './config-parser';
 
 export interface RunnerResults {
   options: RunnerOptions;
@@ -20,7 +20,7 @@ export interface RunnerResults {
   codepoints: CodepointsMap;
 }
 
-export const sanitiseOptions = (userOptions: any) =>
+export const sanitiseOptions = async (userOptions: any) =>
   parseConfig({
     ...DEFAULT_OPTIONS,
     ...userOptions
diff --git a/src/generators/asset-types/__tests__/css.ts b/src/generators/asset-types/__tests__/css.ts
index b83d587f..b6e20ae0 100644
--- a/src/generators/asset-types/__tests__/css.ts
+++ b/src/generators/asset-types/__tests__/css.ts
@@ -1,6 +1,7 @@
-import cssGen from '../css';
-import { renderSrcAttribute } from '../../../utils/css';
+import { Buffer } from 'buffer';
 import { resolve } from 'path';
+import { renderSrcAttribute } from '../../../utils/css';
+import cssGen from '../css';
 
 const renderSrcMock = renderSrcAttribute as any as jest.Mock;
 
diff --git a/src/generators/asset-types/__tests__/eot.ts b/src/generators/asset-types/__tests__/eot.ts
index c6e917d1..d6f02e49 100644
--- a/src/generators/asset-types/__tests__/eot.ts
+++ b/src/generators/asset-types/__tests__/eot.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import _ttf2eot from 'ttf2eot';
 import { FontGeneratorOptions } from '../../../types/generator';
 import eotGen from '../eot';
@@ -9,7 +10,7 @@ jest.mock('ttf2eot', () =>
 );
 
 const mockOptions = (eotOptions = { __mock: 'options__' } as any) =>
-  ({}) as unknown as FontGeneratorOptions;
+  ({} as unknown as FontGeneratorOptions);
 
 const ttf = '::ttf::' as unknown as Buffer;
 
diff --git a/src/generators/asset-types/__tests__/html.ts b/src/generators/asset-types/__tests__/html.ts
index 1d7df909..e3cb034a 100644
--- a/src/generators/asset-types/__tests__/html.ts
+++ b/src/generators/asset-types/__tests__/html.ts
@@ -1,5 +1,5 @@
-import htmlGen from '../html';
 import { resolve } from 'path';
+import htmlGen from '../html';
 
 const mockOptions = {
   name: 'test-font',
diff --git a/src/generators/asset-types/__tests__/json.ts b/src/generators/asset-types/__tests__/json.ts
index 57808888..dd1f47a7 100644
--- a/src/generators/asset-types/__tests__/json.ts
+++ b/src/generators/asset-types/__tests__/json.ts
@@ -1,6 +1,6 @@
-import jsonGen from '../json';
-import { OtherAssetType } from '../../../types/misc';
 import { DEFAULT_OPTIONS } from '../../../constants';
+import { OtherAssetType } from '../../../types/misc';
+import jsonGen from '../json';
 
 const mockCodepoints = { foo: 'oof', bar: 'baz' };
 
@@ -8,7 +8,7 @@ const mockOptions = (jsonOptions: any = {}) =>
   ({
     codepoints: mockCodepoints,
     formatOptions: { [OtherAssetType.JSON]: jsonOptions }
-  }) as any;
+  } as any);
 
 const renderAndParse = async (jsonOptions?: any) =>
   JSON.parse(
diff --git a/src/generators/asset-types/__tests__/sass.ts b/src/generators/asset-types/__tests__/sass.ts
index 9c96038a..868ecdc9 100644
--- a/src/generators/asset-types/__tests__/sass.ts
+++ b/src/generators/asset-types/__tests__/sass.ts
@@ -1,6 +1,7 @@
-import sassGen from '../sass';
-import { renderSrcAttribute } from '../../../utils/css';
+import { Buffer } from 'buffer';
 import { resolve } from 'path';
+import { renderSrcAttribute } from '../../../utils/css';
+import sassGen from '../sass';
 
 const renderSrcMock = renderSrcAttribute as any as jest.Mock;
 
diff --git a/src/generators/asset-types/__tests__/scss.ts b/src/generators/asset-types/__tests__/scss.ts
index 248e616a..a0f9a926 100644
--- a/src/generators/asset-types/__tests__/scss.ts
+++ b/src/generators/asset-types/__tests__/scss.ts
@@ -1,6 +1,7 @@
-import scssGen from '../scss';
-import { renderSrcAttribute } from '../../../utils/css';
+import { Buffer } from 'buffer';
 import { resolve } from 'path';
+import { renderSrcAttribute } from '../../../utils/css';
+import scssGen from '../scss';
 
 const renderSrcMock = renderSrcAttribute as any as jest.Mock;
 
diff --git a/src/generators/asset-types/__tests__/svg.ts b/src/generators/asset-types/__tests__/svg.ts
index 1b7dc9dd..3200dcfb 100644
--- a/src/generators/asset-types/__tests__/svg.ts
+++ b/src/generators/asset-types/__tests__/svg.ts
@@ -1,6 +1,8 @@
+import { Buffer } from 'buffer';
+import EventEmitter from 'events';
 import * as _SVGIcons2SVGFontStream from 'svgicons2svgfont';
-import { FontAssetType } from '../../../types/misc';
 import { FontGeneratorOptions } from '../../../types/generator';
+import { FontAssetType } from '../../../types/misc';
 import svgGen from '../svg';
 
 const SVGIcons2SVGFontStream = _SVGIcons2SVGFontStream as unknown as jest.Mock<
@@ -14,8 +16,6 @@ jest.mock('fs', () => ({
 }));
 
 jest.mock('svgicons2svgfont', () => {
-  const { EventEmitter } = require('events');
-
   class MockStream {
     public events = new EventEmitter();
     public content = '';
@@ -56,7 +56,7 @@ const mockOptions = (svgOptions = { __mock: 'options__' } as any) =>
       foo: { id: 'foo', absolutePath: '/root/foo.svg' },
       bar: { id: 'bar', absolutePath: '/root/bar.svg' }
     }
-  }) as unknown as FontGeneratorOptions;
+  } as unknown as FontGeneratorOptions);
 
 describe('`SVG` font generator', () => {
   beforeEach(() => {
diff --git a/src/generators/asset-types/__tests__/ts.ts b/src/generators/asset-types/__tests__/ts.ts
index 3f425945..87133bd3 100644
--- a/src/generators/asset-types/__tests__/ts.ts
+++ b/src/generators/asset-types/__tests__/ts.ts
@@ -1,5 +1,5 @@
+import { dirname, join } from 'path';
 import tsGen from '../ts';
-import { join, dirname } from 'path';
 
 const mockAssets = {
   foo: {
diff --git a/src/generators/asset-types/__tests__/ttf.ts b/src/generators/asset-types/__tests__/ttf.ts
index 7167c985..e715ab51 100644
--- a/src/generators/asset-types/__tests__/ttf.ts
+++ b/src/generators/asset-types/__tests__/ttf.ts
@@ -1,6 +1,7 @@
+import { Buffer } from 'buffer';
 import _svg2ttf from 'svg2ttf';
-import { FontAssetType } from '../../../types/misc';
 import { FontGeneratorOptions } from '../../../types/generator';
+import { FontAssetType } from '../../../types/misc';
 import ttfGen from '../ttf';
 
 const svg2ttf = _svg2ttf as unknown as jest.Mock<typeof _svg2ttf>;
@@ -12,7 +13,7 @@ jest.mock('svg2ttf', () =>
 const mockOptions = (ttfOptions = { __mock: 'options__' } as any) =>
   ({
     formatOptions: { [FontAssetType.TTF]: ttfOptions }
-  }) as unknown as FontGeneratorOptions;
+  } as unknown as FontGeneratorOptions);
 
 const svg = '::svg::';
 
diff --git a/src/generators/asset-types/__tests__/woff.ts b/src/generators/asset-types/__tests__/woff.ts
index 08bdd878..dbbe1721 100644
--- a/src/generators/asset-types/__tests__/woff.ts
+++ b/src/generators/asset-types/__tests__/woff.ts
@@ -1,6 +1,7 @@
+import { Buffer } from 'buffer';
 import _ttf2woff from 'ttf2woff';
-import { FontAssetType } from '../../../types/misc';
 import { FontGeneratorOptions } from '../../../types/generator';
+import { FontAssetType } from '../../../types/misc';
 import woffGen from '../woff';
 
 const ttf2woff = _ttf2woff as unknown as jest.Mock<typeof _ttf2woff>;
@@ -12,7 +13,7 @@ jest.mock('ttf2woff', () =>
 const mockOptions = (woffOptions = { __mock: 'options__' } as any) =>
   ({
     formatOptions: { [FontAssetType.WOFF]: woffOptions }
-  }) as unknown as FontGeneratorOptions;
+  } as unknown as FontGeneratorOptions);
 
 const ttf = '::ttf::' as unknown as Buffer;
 
diff --git a/src/generators/asset-types/__tests__/woff2.ts b/src/generators/asset-types/__tests__/woff2.ts
index ecec214a..dd608872 100644
--- a/src/generators/asset-types/__tests__/woff2.ts
+++ b/src/generators/asset-types/__tests__/woff2.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import _ttf2woff2 from 'ttf2woff2';
 import { FontGeneratorOptions } from '../../../types/generator';
 import woff2Gen from '../woff2';
@@ -9,7 +10,7 @@ jest.mock('ttf2woff2', () =>
 );
 
 const mockOptions = (woffOptions = { __mock: 'options__' } as any) =>
-  ({}) as unknown as FontGeneratorOptions;
+  ({} as unknown as FontGeneratorOptions);
 
 const ttf = '::ttf::' as unknown as Buffer;
 
diff --git a/src/generators/asset-types/css.ts b/src/generators/asset-types/css.ts
index 847d0221..f55b9586 100644
--- a/src/generators/asset-types/css.ts
+++ b/src/generators/asset-types/css.ts
@@ -1,12 +1,13 @@
+import { Buffer } from 'buffer';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
-import { renderTemplate } from '../../utils/template';
 import { renderSrcAttribute } from '../../utils/css';
+import { renderTemplate } from '../../utils/template';
 
 const generator: FontGenerator<Buffer> = {
   dependsOn: FontAssetType.SVG,
 
-  generate: (options, svg: Buffer) =>
+  generate: async (options, svg: Buffer) =>
     renderTemplate(options.templates.css, {
       ...options,
       fontSrc: renderSrcAttribute(options, svg)
diff --git a/src/generators/asset-types/eot.ts b/src/generators/asset-types/eot.ts
index c48797a7..bcfb4412 100644
--- a/src/generators/asset-types/eot.ts
+++ b/src/generators/asset-types/eot.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import ttf2eot from 'ttf2eot';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
diff --git a/src/generators/asset-types/html.ts b/src/generators/asset-types/html.ts
index 67087801..384fa759 100644
--- a/src/generators/asset-types/html.ts
+++ b/src/generators/asset-types/html.ts
@@ -2,7 +2,7 @@ import { FontGenerator } from '../../types/generator';
 import { renderTemplate } from '../../utils/template';
 
 const generator: FontGenerator = {
-  generate: async options => {
+  async generate(options) {
     return renderTemplate(options.templates.html, options);
   }
 };
diff --git a/src/generators/asset-types/index.ts b/src/generators/asset-types/index.ts
index 77de9e82..de149768 100644
--- a/src/generators/asset-types/index.ts
+++ b/src/generators/asset-types/index.ts
@@ -1,16 +1,16 @@
-import { AssetType, FontAssetType, OtherAssetType } from '../../types/misc';
 import { FontGenerator } from '../../types/generator';
-import svg from './svg';
-import ttf from './ttf';
-import woff from './woff';
-import woff2 from './woff2';
-import eot from './eot';
+import { AssetType, FontAssetType, OtherAssetType } from '../../types/misc';
 import css from './css';
+import eot from './eot';
 import html from './html';
 import json from './json';
-import ts from './ts';
 import sass from './sass';
 import scss from './scss';
+import svg from './svg';
+import ts from './ts';
+import ttf from './ttf';
+import woff from './woff';
+import woff2 from './woff2';
 
 const generators: { [key in AssetType]: FontGenerator<any> } = {
   [FontAssetType.SVG]: svg,
diff --git a/src/generators/asset-types/sass.ts b/src/generators/asset-types/sass.ts
index 7ac2daac..02d1719e 100644
--- a/src/generators/asset-types/sass.ts
+++ b/src/generators/asset-types/sass.ts
@@ -1,12 +1,13 @@
+import { Buffer } from 'buffer';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
-import { renderTemplate } from '../../utils/template';
 import { renderSrcAttribute } from '../../utils/css';
+import { renderTemplate } from '../../utils/template';
 
 const generator: FontGenerator<Buffer> = {
   dependsOn: FontAssetType.SVG,
 
-  generate: (options, svg: Buffer) =>
+  generate: async (options, svg: Buffer) =>
     renderTemplate(options.templates.sass, {
       ...options,
       fontSrc: renderSrcAttribute(options, svg)
diff --git a/src/generators/asset-types/scss.ts b/src/generators/asset-types/scss.ts
index 252f9a72..1453f6bd 100644
--- a/src/generators/asset-types/scss.ts
+++ b/src/generators/asset-types/scss.ts
@@ -1,12 +1,13 @@
+import { Buffer } from 'buffer';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
-import { renderTemplate } from '../../utils/template';
 import { renderSrcAttribute } from '../../utils/css';
+import { renderTemplate } from '../../utils/template';
 
 const generator: FontGenerator<Buffer> = {
   dependsOn: FontAssetType.SVG,
 
-  generate: (options, svg: Buffer) =>
+  generate: async (options, svg: Buffer) =>
     renderTemplate(
       options.templates.scss,
       { ...options, fontSrc: renderSrcAttribute(options, svg) },
diff --git a/src/generators/asset-types/svg.ts b/src/generators/asset-types/svg.ts
index 4a39e6da..4021cd02 100644
--- a/src/generators/asset-types/svg.ts
+++ b/src/generators/asset-types/svg.ts
@@ -1,11 +1,12 @@
+import { Buffer } from 'buffer';
 import { createReadStream, ReadStream } from 'fs';
 import SVGIcons2SVGFontStream from 'svgicons2svgfont';
 import { FontGenerator } from '../../types/generator';
 
 type GglyphStream = ReadStream & { metadata?: any };
 
-const generator: FontGenerator<void> = {
-  generate: ({
+const generator: FontGenerator = {
+  generate: async ({
     name: fontName,
     fontHeight,
     descent,
@@ -25,8 +26,13 @@ const generator: FontGenerator<void> = {
         log: () => null,
         ...svg
       })
-        .on('data', data => (font = Buffer.concat([font, data])))
-        .on('end', () => resolve(font.toString()));
+        .on('data', data => {
+          font = Buffer.concat([font, data]);
+          return font;
+        })
+        .on('end', () => {
+          resolve(font.toString());
+        });
 
       for (const { id, absolutePath } of Object.values(assets)) {
         const glyph: GglyphStream = createReadStream(absolutePath);
diff --git a/src/generators/asset-types/ts.ts b/src/generators/asset-types/ts.ts
index 159bb0cc..a943f056 100644
--- a/src/generators/asset-types/ts.ts
+++ b/src/generators/asset-types/ts.ts
@@ -5,7 +5,7 @@ const generateEnumKeys = (assetKeys: string[]): Record<string, string> =>
   assetKeys
     .map(name => {
       const enumName = pascalCase(name);
-      const prefix = enumName.match(/^\d/) ? 'i' : '';
+      const prefix = /^\d/.test(enumName) ? 'i' : '';
 
       return {
         [name]: `${prefix}${enumName}`
@@ -80,15 +80,10 @@ const generateStringLiterals = (
   ].join('\n');
 
 const generator: FontGenerator = {
-  generate: async ({
-    name,
-    codepoints,
-    assets,
-    formatOptions: { ts } = {}
-  }) => {
-    const quote = Boolean(ts?.singleQuotes) ? "'" : '"';
+  async generate({ name, codepoints, assets, formatOptions: { ts } = {} }) {
+    const quote = ts?.singleQuotes ? "'" : '"';
     const generateKind: Record<string, boolean> = (
-      Boolean(ts?.types?.length)
+      ts?.types?.length
         ? ts.types
         : ['enum', 'constant', 'literalId', 'literalKey']
     )
diff --git a/src/generators/asset-types/ttf.ts b/src/generators/asset-types/ttf.ts
index 69662f09..e1d0991b 100644
--- a/src/generators/asset-types/ttf.ts
+++ b/src/generators/asset-types/ttf.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import svg2ttf from 'svg2ttf';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
@@ -6,7 +7,7 @@ const generator: FontGenerator<string> = {
   dependsOn: FontAssetType.SVG,
 
   async generate({ formatOptions }, svg) {
-    const font = svg2ttf(svg, { ts: 0, ...(formatOptions?.ttf || {}) });
+    const font = svg2ttf(svg, { ts: 0, ...formatOptions?.ttf });
     return Buffer.from(font.buffer);
   }
 };
diff --git a/src/generators/asset-types/woff.ts b/src/generators/asset-types/woff.ts
index e202e3a0..697d0dee 100644
--- a/src/generators/asset-types/woff.ts
+++ b/src/generators/asset-types/woff.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import ttf2woff from 'ttf2woff';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
diff --git a/src/generators/asset-types/woff2.ts b/src/generators/asset-types/woff2.ts
index a834ce67..1f2b4f1f 100644
--- a/src/generators/asset-types/woff2.ts
+++ b/src/generators/asset-types/woff2.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import ttf2woff2 from 'ttf2woff2';
 import { FontGenerator } from '../../types/generator';
 import { FontAssetType } from '../../types/misc';
diff --git a/src/generators/generate-assets.ts b/src/generators/generate-assets.ts
index ef4f9d9e..51601a76 100644
--- a/src/generators/generate-assets.ts
+++ b/src/generators/generate-assets.ts
@@ -1,5 +1,6 @@
-import { AssetType, FontAssetType, OtherAssetType } from '../types/misc';
+import { Buffer } from 'buffer';
 import { FontGeneratorOptions } from '../types/generator';
+import { AssetType, FontAssetType, OtherAssetType } from '../types/misc';
 import generators from './asset-types';
 
 export type GeneratedAssets = {
@@ -24,18 +25,19 @@ export const generateAssets = async (
       generated[dependsOn] = await generateAsset(dependsOn);
     }
 
-    return (generated[type] = await generator.generate(
+    generated[type] = await generator.generate(
       options,
       dependsOn ? generated[dependsOn] : null
-    ));
+    );
+
+    return generated[type];
   };
 
   for (const type of generateTypes) {
     await generateAsset(type);
   }
 
-  return generateTypes.reduce(
-    (out, type: AssetType) => ({ ...out, [type]: generated[type] }),
-    {}
+  return Object.fromEntries(
+    generateTypes.map((type: AssetType) => [type, generated[type]])
   );
 };
diff --git a/src/generators/generator-options.ts b/src/generators/generator-options.ts
index abb9b01a..bff55b32 100644
--- a/src/generators/generator-options.ts
+++ b/src/generators/generator-options.ts
@@ -1,16 +1,16 @@
 import { join } from 'path';
 import { DEFAULT_OPTIONS, TEMPLATES_DIR } from '../constants';
-import { RunnerOptions } from '../types/runner';
 import { FormatOptions } from '../types/format';
-import { getCodepoints } from '../utils/codepoints';
 import { FontGeneratorOptions } from '../types/generator';
 import {
   AssetType,
-  OtherAssetType,
   ASSET_TYPES,
-  ASSET_TYPES_WITH_TEMPLATE
+  ASSET_TYPES_WITH_TEMPLATE,
+  OtherAssetType
 } from '../types/misc';
+import { RunnerOptions } from '../types/runner';
 import { AssetsMap } from '../utils/assets';
+import { getCodepoints } from '../utils/codepoints';
 
 export const getGeneratorOptions = (
   options: RunnerOptions,
diff --git a/src/index.ts b/src/index.ts
index 49fb275a..a1336b7d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,12 +1,12 @@
+export { generateFonts as default, generateFonts } from './core/runner';
+
 export {
-  FontAssetType,
-  OtherAssetType,
-  ASSET_TYPES,
   AssetType,
+  ASSET_TYPES,
+  FontAssetType,
   GetIconIdFn,
-  GetIconIdOptions
+  GetIconIdOptions,
+  OtherAssetType
 } from './types/misc';
 
 export { RunnerOptions } from './types/runner';
-
-export { generateFonts, generateFonts as default } from './core/runner';
diff --git a/src/types/format.ts b/src/types/format.ts
index b7f15b85..bdc42229 100644
--- a/src/types/format.ts
+++ b/src/types/format.ts
@@ -1,7 +1,7 @@
 import svg2ttf from 'svg2ttf';
-import ttf2woff from 'ttf2woff';
 import { SvgIcons2FontOptions } from 'svgicons2svgfont';
-import { Arguments } from '../types/utils';
+import ttf2woff from 'ttf2woff';
+import { Arguments } from './utils';
 
 type WoffOptions = Arguments<typeof ttf2woff>[1];
 type TtfOptions = svg2ttf.FontOptions;
@@ -15,7 +15,7 @@ interface JsonOptions {
 }
 
 interface TsOptions {
-  types?: ('enum' | 'constant' | 'literalId' | 'literalKey')[];
+  types?: Array<'enum' | 'constant' | 'literalId' | 'literalKey'>;
   singleQuotes?: boolean;
   enumName?: string;
   constantName?: string;
diff --git a/src/types/generator.ts b/src/types/generator.ts
index 17e1176a..bd2cedef 100644
--- a/src/types/generator.ts
+++ b/src/types/generator.ts
@@ -1,7 +1,8 @@
+import { Buffer } from 'buffer';
 import { AssetsMap } from '../utils/assets';
+import { FormatOptions } from './format';
 import { AssetType, OtherAssetType } from './misc';
 import { RunnerOptions } from './runner';
-import { FormatOptions } from './format';
 
 export type FontGeneratorOptions = RunnerOptions & {
   assets: AssetsMap;
diff --git a/src/types/runner.ts b/src/types/runner.ts
index 176422c3..e89f29c5 100644
--- a/src/types/runner.ts
+++ b/src/types/runner.ts
@@ -1,6 +1,6 @@
 import { CodepointsMap } from '../utils/codepoints';
-import { FontAssetType, OtherAssetType, AssetType, GetIconIdFn } from './misc';
 import { FormatOptions } from './format';
+import { AssetType, FontAssetType, GetIconIdFn, OtherAssetType } from './misc';
 
 export interface RunnerMandatoryOptions {
   inputDir: string;
diff --git a/src/utils/__tests__/assets.ts b/src/utils/__tests__/assets.ts
index f8952305..515e3927 100644
--- a/src/utils/__tests__/assets.ts
+++ b/src/utils/__tests__/assets.ts
@@ -8,7 +8,7 @@ const writeFileMock = writeFile as any as jest.Mock;
 jest.mock('path');
 jest.mock('glob');
 jest.mock('fs/promises', () => ({
-  writeFile: jest.fn(() => Promise.resolve())
+  writeFile: jest.fn()
 }));
 
 describe('Assets utilities', () => {
@@ -27,7 +27,7 @@ describe('Assets utilities', () => {
       expect(paths).toBeInstanceOf(Array);
       expect(paths.length).toBeTruthy();
 
-      paths.forEach(path => expect(typeof path).toBe('string'));
+      for (const path of paths) expect(typeof path).toBe('string');
     });
 
     it('resolves an Array of the correct filepaths within the given directory', async () => {
@@ -144,12 +144,12 @@ describe('Assets utilities', () => {
     it('rejects correctly if `getIconId` resolves the same `key` while processing different assets', async () => {
       const getIconId: GetIconIdFn = () => 'xxx';
 
-      await expect(() =>
+      await expect(async () =>
         loadAssets({
           ...DEFAULT_OPTIONS,
           inputDir: './valid',
           outputDir: './output',
-          getIconId: getIconId
+          getIconId
         })
       ).rejects.toEqual(
         new Error(
diff --git a/src/utils/__tests__/css.ts b/src/utils/__tests__/css.ts
index e18e36fb..ccee606b 100644
--- a/src/utils/__tests__/css.ts
+++ b/src/utils/__tests__/css.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import { renderSrcAttribute } from '../css';
 import { FontAssetType } from '../../types/misc';
 import * as hashUtils from '../hash';
diff --git a/src/utils/__tests__/fs-async.ts b/src/utils/__tests__/fs-async.ts
index b0d7d639..de5d28a6 100644
--- a/src/utils/__tests__/fs-async.ts
+++ b/src/utils/__tests__/fs-async.ts
@@ -16,7 +16,8 @@ describe('Async FS utilities', () => {
     it('calls `stat` correctly and correctly check the existance of a path', async () => {
       const mockPath = '/dev/null';
 
-      statMock.mockImplementationOnce(() => Promise.resolve());
+      // eslint-disable-next-line @typescript-eslint/no-empty-function
+      statMock.mockImplementationOnce(async () => {});
 
       expect(await checkPath(mockPath)).toBe(true);
       expect(statMock).toHaveBeenCalledTimes(1);
@@ -34,7 +35,7 @@ describe('Async FS utilities', () => {
       const mockPath = '/dev/null';
       const isDirectory = jest.fn(() => false);
 
-      statMock.mockImplementation(() => Promise.resolve({ isDirectory }));
+      statMock.mockImplementation(async () => ({ isDirectory }));
 
       expect(await checkPath(mockPath, 'directory')).toBe(false);
       expect(statMock).toHaveBeenCalledTimes(1);
@@ -50,7 +51,7 @@ describe('Async FS utilities', () => {
       const mockPath = '/dev/null';
       const isFile = jest.fn(() => false);
 
-      statMock.mockImplementation(() => Promise.resolve({ isFile }));
+      statMock.mockImplementation(async () => ({ isFile }));
 
       expect(await checkPath(mockPath, 'file')).toBe(false);
       expect(statMock).toHaveBeenCalledTimes(1);
diff --git a/src/utils/__tests__/hash.ts b/src/utils/__tests__/hash.ts
index d2d8e4ab..76265ffd 100644
--- a/src/utils/__tests__/hash.ts
+++ b/src/utils/__tests__/hash.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import { getHash } from '../hash';
 
 describe('Hash utilities', () => {
diff --git a/src/utils/__tests__/validation.ts b/src/utils/__tests__/validation.ts
index 63752809..cf07677a 100644
--- a/src/utils/__tests__/validation.ts
+++ b/src/utils/__tests__/validation.ts
@@ -32,7 +32,7 @@ describe('Cli utilities', () => {
     it.each(['a', {}, undefined, true, false, null])(
       'throws an error when given a non-numeric value - input: %s',
       input => {
-        expect(() => parseNumeric(input as any)).toThrow(
+        expect(() => parseNumeric(input as unknown as any)).toThrow(
           `${input} is not a valid number`
         );
       }
@@ -48,9 +48,10 @@ describe('Cli utilities', () => {
     );
 
     it('throws an error when given a non-string value', () => {
-      for (const value of [1, true, {}, undefined, null, false]) {
+      const values = [1, true, {}, undefined, null, false];
+      for (const value of values) {
         expect(() => parseString(value as any)).toThrow(
-          `${value} is not a string`
+          `${value} is not a string` // eslint-disable-line @typescript-eslint/no-base-to-string
         );
       }
     });
@@ -63,6 +64,7 @@ describe('Cli utilities', () => {
       expect(parseFunction(fn)).toBe(fn);
     });
 
+    // eslint-disable-next-line prefer-regex-literals
     it.each([null, undefined, '', 'foo', 10, {}, new RegExp('foo')])(
       '`parseFunction` throws expected error if given path is found not to be a function - input: %s',
       input => {
@@ -164,7 +166,7 @@ describe('Cli utilities', () => {
     it('calls `checkPath` correctly and returns unchanged path if found to be an existing directory', async () => {
       const dirname = '/foo/bar';
 
-      checkPathMock.mockImplementationOnce(() => Promise.resolve(true));
+      checkPathMock.mockImplementationOnce(async () => true);
 
       expect(await parseDir(dirname)).toBe(dirname);
       expect(checkPathMock).toHaveBeenCalledTimes(1);
@@ -174,9 +176,9 @@ describe('Cli utilities', () => {
     it('throws expected error if given path is found not to be a directory', async () => {
       const dirname = '/foo/bar';
 
-      checkPathMock.mockImplementationOnce(() => Promise.resolve(false));
+      checkPathMock.mockImplementationOnce(async () => false);
 
-      await expect(() => parseDir(dirname)).rejects.toThrow(
+      await expect(async () => parseDir(dirname)).rejects.toThrow(
         '/foo/bar is not a directory'
       );
     });
diff --git a/src/utils/assets.ts b/src/utils/assets.ts
index 12e615d7..ba7e9e43 100644
--- a/src/utils/assets.ts
+++ b/src/utils/assets.ts
@@ -1,10 +1,11 @@
+import { Buffer } from 'buffer';
 import { writeFile } from 'fs/promises';
-import glob from 'glob';
 import { join, relative, resolve } from 'path';
 import { promisify } from 'util';
+import glob from 'glob';
 import { GeneratedAssets } from '../generators/generate-assets';
 import { RunnerOptions } from '../types/runner';
-import { removeExtension, splitSegments } from '../utils/path';
+import { removeExtension, splitSegments } from './path';
 
 export type WriteResult = { content: string | Buffer; writePath: string };
 
@@ -27,7 +28,7 @@ export const loadPaths = async (dir: string): Promise<string[]> => {
 
   const files = await promisify(glob)(globPath, {});
 
-  if (!files.length) {
+  if (files.length === 0) {
     throw new Error(`No SVGs found in ${dir}`);
   }
 
diff --git a/src/utils/css.ts b/src/utils/css.ts
index afbe76f2..424a7502 100644
--- a/src/utils/css.ts
+++ b/src/utils/css.ts
@@ -1,6 +1,7 @@
+import { Buffer } from 'buffer';
 import { FontGeneratorOptions } from '../types/generator';
-import { getHash } from './hash';
 import { FontAssetType } from '../types/misc';
+import { getHash } from './hash';
 
 interface RenderSrcOptions {
   formatValue: string;
diff --git a/src/utils/fs-async.ts b/src/utils/fs-async.ts
index 668ebae1..f2a1d720 100644
--- a/src/utils/fs-async.ts
+++ b/src/utils/fs-async.ts
@@ -12,7 +12,7 @@ export const checkPath = async (
     }
 
     return true;
-  } catch (err) {
+  } catch {
     return false;
   }
 };
diff --git a/src/utils/hash.ts b/src/utils/hash.ts
index 10519ebe..b9555a27 100644
--- a/src/utils/hash.ts
+++ b/src/utils/hash.ts
@@ -1,3 +1,4 @@
+import { Buffer } from 'buffer';
 import crypto from 'crypto';
 
 export const getHash = (...contents: Array<string | Buffer>) => {
diff --git a/src/utils/icon-id.ts b/src/utils/icon-id.ts
index d75f5777..f4c246f2 100644
--- a/src/utils/icon-id.ts
+++ b/src/utils/icon-id.ts
@@ -1,9 +1,9 @@
+import slug from 'slugify';
 import { GetIconIdFn } from '../types/misc';
 import { removeExtension } from './path';
-import slug from 'slugify';
 
 export const getIconId: GetIconIdFn = ({ relativeFilePath }) =>
-  slug(removeExtension(relativeFilePath).replace(/(\/|\\|\.)+/g, '-'), {
+  slug(removeExtension(relativeFilePath).replace(/([./\\])+/g, '-'), {
     replacement: '-',
     remove: /['"`]/g
   });
diff --git a/src/utils/template.ts b/src/utils/template.ts
index ab9ed8de..064367bc 100644
--- a/src/utils/template.ts
+++ b/src/utils/template.ts
@@ -1,6 +1,7 @@
 import { readFile } from 'fs/promises';
-import Handlebars from 'handlebars';
 import { isAbsolute, resolve } from 'path';
+import process from 'process';
+import Handlebars from 'handlebars';
 import { getHexCodepoint } from './codepoints';
 
 export const TEMPLATE_HELPERS: Record<string, Function> = {
@@ -23,6 +24,6 @@ export const renderTemplate = async (
 
   return Handlebars.compile(template)(context, {
     ...options,
-    helpers: { ...TEMPLATE_HELPERS, ...(options.helpers || {}) }
+    helpers: { ...TEMPLATE_HELPERS, ...options.helpers }
   });
 };
diff --git a/src/utils/validation.ts b/src/utils/validation.ts
index a40ebd14..df9fc54a 100644
--- a/src/utils/validation.ts
+++ b/src/utils/validation.ts
@@ -48,8 +48,8 @@ export const listMembersParser =
 
 export const removeUndefined = (object: Object) => {
   for (const key of Object.keys(object)) {
-    if (typeof object[key] === 'undefined') {
-      delete object[key];
+    if (object[key] === undefined) {
+      delete object[key]; // eslint-disable-line @typescript-eslint/no-dynamic-delete
     }
   }
 
@@ -59,9 +59,13 @@ export const removeUndefined = (object: Object) => {
 export const parseBoolean = (val: any) => {
   if (typeof val === 'string' && ['1', '0', 'true', 'false'].includes(val)) {
     return val === 'true' || val === '1';
-  } else if (typeof val === 'number' && [0, 1].includes(val)) {
+  }
+
+  if (typeof val === 'number' && [0, 1].includes(val)) {
     return val === 1;
-  } else if (typeof val === 'boolean') {
+  }
+
+  if (typeof val === 'boolean') {
     return val;
   }