diff --git a/tests/shared/utils.spec.js b/tests/shared/utils.spec.js
deleted file mode 100644
index dd27c915..00000000
--- a/tests/shared/utils.spec.js
+++ /dev/null
@@ -1,129 +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 m = require('mochainon')
-// eslint-disable-next-line node/no-missing-require
-const utils = require('../../lib/shared/utils')
-
-describe('Shared: Utils', function () {
-  describe('.isValidPercentage()', function () {
-    it('should return false if percentage is not a number', function () {
-      m.chai.expect(utils.isValidPercentage('50')).to.be.false
-    })
-
-    it('should return false if percentage is null', function () {
-      m.chai.expect(utils.isValidPercentage(null)).to.be.false
-    })
-
-    it('should return false if percentage is undefined', function () {
-      m.chai.expect(utils.isValidPercentage(undefined)).to.be.false
-    })
-
-    it('should return false if percentage is an integer less than 0', function () {
-      m.chai.expect(utils.isValidPercentage(-1)).to.be.false
-    })
-
-    it('should return false if percentage is a float less than 0', function () {
-      m.chai.expect(utils.isValidPercentage(-0.1)).to.be.false
-    })
-
-    it('should return true if percentage is 0', function () {
-      m.chai.expect(utils.isValidPercentage(0)).to.be.true
-    })
-
-    it('should return true if percentage is an integer greater than 0, but less than 100', function () {
-      m.chai.expect(utils.isValidPercentage(50)).to.be.true
-    })
-
-    it('should return true if percentage is a float greater than 0, but less than 100', function () {
-      m.chai.expect(utils.isValidPercentage(49.55)).to.be.true
-    })
-
-    it('should return true if percentage is 100', function () {
-      m.chai.expect(utils.isValidPercentage(100)).to.be.true
-    })
-
-    it('should return false if percentage is an integer greater than 100', function () {
-      m.chai.expect(utils.isValidPercentage(101)).to.be.false
-    })
-
-    it('should return false if percentage is a float greater than 100', function () {
-      m.chai.expect(utils.isValidPercentage(100.001)).to.be.false
-    })
-  })
-
-  describe('.percentageToFloat()', function () {
-    it('should throw an error if given a string percentage', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat('50')
-      }).to.throw('Invalid percentage: 50')
-    })
-
-    it('should throw an error if given a null percentage', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(null)
-      }).to.throw('Invalid percentage: null')
-    })
-
-    it('should throw an error if given an undefined percentage', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(undefined)
-      }).to.throw('Invalid percentage: undefined')
-    })
-
-    it('should throw an error if given an integer percentage < 0', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(-1)
-      }).to.throw('Invalid percentage: -1')
-    })
-
-    it('should throw an error if given a float percentage < 0', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(-0.1)
-      }).to.throw('Invalid percentage: -0.1')
-    })
-
-    it('should covert a 0 percentage to 0', function () {
-      m.chai.expect(utils.percentageToFloat(0)).to.equal(0)
-    })
-
-    it('should covert an integer percentage to a float', function () {
-      m.chai.expect(utils.percentageToFloat(50)).to.equal(0.5)
-    })
-
-    it('should covert an float percentage to a float', function () {
-      m.chai.expect(utils.percentageToFloat(46.54)).to.equal(0.4654)
-    })
-
-    it('should covert a 100 percentage to 1', function () {
-      m.chai.expect(utils.percentageToFloat(100)).to.equal(1)
-    })
-
-    it('should throw an error if given an integer percentage > 100', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(101)
-      }).to.throw('Invalid percentage: 101')
-    })
-
-    it('should throw an error if given a float percentage > 100', function () {
-      m.chai.expect(function () {
-        utils.percentageToFloat(100.01)
-      }).to.throw('Invalid percentage: 100.01')
-    })
-  })
-})
diff --git a/tests/shared/utils.spec.ts b/tests/shared/utils.spec.ts
new file mode 100644
index 00000000..3da8b975
--- /dev/null
+++ b/tests/shared/utils.spec.ts
@@ -0,0 +1,127 @@
+/*
+ * 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 { expect } from 'chai';
+
+import * as utils from '../../lib/shared/utils';
+
+describe('Shared: Utils', function() {
+	describe('.isValidPercentage()', function() {
+		it('should return false if percentage is not a number', function() {
+			expect(utils.isValidPercentage('50')).to.be.false;
+		});
+
+		it('should return false if percentage is null', function() {
+			expect(utils.isValidPercentage(null)).to.be.false;
+		});
+
+		it('should return false if percentage is undefined', function() {
+			expect(utils.isValidPercentage(undefined)).to.be.false;
+		});
+
+		it('should return false if percentage is an integer less than 0', function() {
+			expect(utils.isValidPercentage(-1)).to.be.false;
+		});
+
+		it('should return false if percentage is a float less than 0', function() {
+			expect(utils.isValidPercentage(-0.1)).to.be.false;
+		});
+
+		it('should return true if percentage is 0', function() {
+			expect(utils.isValidPercentage(0)).to.be.true;
+		});
+
+		it('should return true if percentage is an integer greater than 0, but less than 100', function() {
+			expect(utils.isValidPercentage(50)).to.be.true;
+		});
+
+		it('should return true if percentage is a float greater than 0, but less than 100', function() {
+			expect(utils.isValidPercentage(49.55)).to.be.true;
+		});
+
+		it('should return true if percentage is 100', function() {
+			expect(utils.isValidPercentage(100)).to.be.true;
+		});
+
+		it('should return false if percentage is an integer greater than 100', function() {
+			expect(utils.isValidPercentage(101)).to.be.false;
+		});
+
+		it('should return false if percentage is a float greater than 100', function() {
+			expect(utils.isValidPercentage(100.001)).to.be.false;
+		});
+	});
+
+	describe('.percentageToFloat()', function() {
+		it('should throw an error if given a string percentage', function() {
+			expect(function() {
+				utils.percentageToFloat('50');
+			}).to.throw('Invalid percentage: 50');
+		});
+
+		it('should throw an error if given a null percentage', function() {
+			expect(function() {
+				utils.percentageToFloat(null);
+			}).to.throw('Invalid percentage: null');
+		});
+
+		it('should throw an error if given an undefined percentage', function() {
+			expect(function() {
+				utils.percentageToFloat(undefined);
+			}).to.throw('Invalid percentage: undefined');
+		});
+
+		it('should throw an error if given an integer percentage < 0', function() {
+			expect(function() {
+				utils.percentageToFloat(-1);
+			}).to.throw('Invalid percentage: -1');
+		});
+
+		it('should throw an error if given a float percentage < 0', function() {
+			expect(function() {
+				utils.percentageToFloat(-0.1);
+			}).to.throw('Invalid percentage: -0.1');
+		});
+
+		it('should covert a 0 percentage to 0', function() {
+			expect(utils.percentageToFloat(0)).to.equal(0);
+		});
+
+		it('should covert an integer percentage to a float', function() {
+			expect(utils.percentageToFloat(50)).to.equal(0.5);
+		});
+
+		it('should covert an float percentage to a float', function() {
+			expect(utils.percentageToFloat(46.54)).to.equal(0.4654);
+		});
+
+		it('should covert a 100 percentage to 1', function() {
+			expect(utils.percentageToFloat(100)).to.equal(1);
+		});
+
+		it('should throw an error if given an integer percentage > 100', function() {
+			expect(function() {
+				utils.percentageToFloat(101);
+			}).to.throw('Invalid percentage: 101');
+		});
+
+		it('should throw an error if given a float percentage > 100', function() {
+			expect(function() {
+				utils.percentageToFloat(100.01);
+			}).to.throw('Invalid percentage: 100.01');
+		});
+	});
+});