Try typescript

remix-resolve/package.json

@@ -7,6 +7,7 @@
     "remix-resolve": "./bin/remix-resolve"
   },
   "scripts": {
+    "build": "tsc",
     "lint": "standard",
     "test": "standard && mocha tests/ -t 300000"
   },
@@ -35,6 +36,8 @@
   },
   "devDependencies": {
     "mocha": "^5.1.0",
-    "standard": "^12.0.1"
+    "standard": "^12.0.1",
+    "tslint": "^5.11.0",
+    "typescript": "^3.1.6"
   }
 }

remix-resolve/src/index.ts

+/*
+const rr = require('remix-resolve')
+const fileContent = rr.resolve('https://github.com/ethereum/greeter.sol')
+const input = rr.combineSource({ 'greeter.sol': content })
+*/
+export * from './resolve.js'
+export * from './combineSource.js'
+export * from './getFile.js'

remix-resolve/tsconfig.json

+{
+  "compileOnSave": false,
+  "include": ["./src"],
+  "compileOptions": {
+    "baseUrl": "./src",
+    "outDir": "./dist",
+    "sourceMap": false,
+    "declaration": false,
+    "module": "commonjs",
+    "strict": true,
+    "noImplicitAny": false,
+    "strictPropertyInitialization": false,
+    "experimentalDecorators": true,
+    "target": "es5",
+    "typeRoots": ["node_modules/@types"],
+    "lib": ["dom", "es2018"],
+    "paths": {
+        "remix-resolve": ["./"]
+    }
+  }
+}

remix-resolve/tslint.json

+{
+    "rules": {
+      "arrow-return-shorthand": true,
+      "callable-types": true,
+      "class-name": true,
+      "comment-format": [
+        true,
+        "check-space"
+      ],
+      "curly": false,
+      "deprecation": {
+        "severity": "warn"
+      },
+      "forin": false,
+      "import-spacing": true,
+      "indent": [
+        true,
+        "spaces"
+      ],
+      "interface-over-type-literal": true,
+      "label-position": true,
+      "max-line-length": [
+        true,
+        140
+      ],
+      "member-access": false,
+      "member-ordering": [
+        true,
+        {
+          "order": [
+            "static-field",
+            "instance-field",
+            "static-method",
+            "instance-method"
+          ]
+        }
+      ],
+      "no-arg": true,
+      "no-bitwise": false,
+      "no-console": [
+        true,
+        "debug",
+        "info",
+        "time",
+        "timeEnd",
+        "trace"
+      ],
+      "no-construct": true,
+      "no-duplicate-super": true,
+      "no-empty": false,
+      "no-empty-interface": true,
+      "no-eval": true,
+      "no-inferrable-types": [
+        true,
+        "ignore-params"
+      ],
+      "no-misused-new": true,
+      "no-non-null-assertion": true,
+      "no-redundant-jsdoc": true,
+      "no-shadowed-variable": true,
+      "no-string-literal": false,
+      "no-string-throw": true,
+      "no-switch-case-fall-through": true,
+      "no-trailing-whitespace": true,
+      "no-unnecessary-initializer": true,
+      "no-unused-expression": true,
+      "no-use-before-declare": true,
+      "no-var-keyword": true,
+      "object-literal-sort-keys": false,
+      "one-line": [
+        true,
+        "check-open-brace",
+        "check-catch",
+        "check-else",
+        "check-whitespace"
+      ],
+      "prefer-const": true,
+      "quotemark": [
+        false,
+        "single"
+      ],
+      "radix": true,
+      "semicolon": [
+        true,
+        "never"
+      ],
+      "triple-equals": [
+        true,
+        "allow-null-check"
+      ],
+      "typedef-whitespace": [
+        true,
+        {
+          "call-signature": "nospace",
+          "index-signature": "nospace",
+          "parameter": "nospace",
+          "property-declaration": "nospace",
+          "variable-declaration": "nospace"
+        }
+      ],
+      "unified-signatures": true,
+      "variable-name": false,
+      "whitespace": [
+        true,
+        "check-branch",
+        "check-decl",
+        "check-operator",
+        "check-separator",
+        "check-type"
+      ]
+    }
+  }
+