diff --git a/cli/system_loader.js b/cli/system_loader.js
deleted file mode 100644
index bb25bb2dd5..0000000000
--- a/cli/system_loader.js
+++ /dev/null
@@ -1,101 +0,0 @@
-// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
-
-// deno-lint-ignore-file
-
-// This is a specialised implementation of a System module loader.
-
-"use strict";
-
-// @ts-nocheck
-let System, __instantiate;
-(() => {
-  const r = new Map();
-
-  System = {
-    register(id, d, f) {
-      r.set(id, { d, f, exp: {} });
-    },
-  };
-  async function dI(mid, src) {
-    let id = mid.replace(/\.\w+$/i, "");
-    if (id.includes("./")) {
-      const [o, ...ia] = id.split("/").reverse(),
-        [, ...sa] = src.split("/").reverse(),
-        oa = [o];
-      let s = 0,
-        i;
-      while ((i = ia.shift())) {
-        if (i === "..") s++;
-        else if (i === ".") break;
-        else oa.push(i);
-      }
-      if (s < sa.length) oa.push(...sa.slice(s));
-      id = oa.reverse().join("/");
-    }
-    return r.has(id) ? gExpA(id) : import(mid);
-  }
-
-  function gC(id, main) {
-    return {
-      id,
-      import: (m) => dI(m, id),
-      meta: { url: id, main },
-    };
-  }
-
-  function gE(exp) {
-    return (id, v) => {
-      const e = typeof id === "string" ? { [id]: v } : id;
-      for (const [id, value] of Object.entries(e)) {
-        Object.defineProperty(exp, id, {
-          value,
-          writable: true,
-          enumerable: true,
-        });
-      }
-      return v;
-    };
-  }
-
-  function rF(main) {
-    for (const [id, m] of r.entries()) {
-      const { f, exp } = m;
-      const { execute: e, setters: s } = f(gE(exp), gC(id, id === main));
-      delete m.f;
-      m.e = e;
-      m.s = s;
-    }
-  }
-
-  async function gExpA(id) {
-    if (!r.has(id)) return;
-    const m = r.get(id);
-    if (m.s) {
-      const { d, e, s } = m;
-      delete m.s;
-      delete m.e;
-      for (let i = 0; i < s.length; i++) s[i](await gExpA(d[i]));
-      const r = e();
-      if (r) await r;
-    }
-    return m.exp;
-  }
-
-  function gExp(id) {
-    if (!r.has(id)) return;
-    const m = r.get(id);
-    if (m.s) {
-      const { d, e, s } = m;
-      delete m.s;
-      delete m.e;
-      for (let i = 0; i < s.length; i++) s[i](gExp(d[i]));
-      e();
-    }
-    return m.exp;
-  }
-  __instantiate = (m, a) => {
-    System = __instantiate = undefined;
-    rF(m);
-    return a ? gExpA(m) : gExp(m);
-  };
-})();
diff --git a/cli/system_loader_es5.js b/cli/system_loader_es5.js
deleted file mode 100644
index daf941d765..0000000000
--- a/cli/system_loader_es5.js
+++ /dev/null
@@ -1,182 +0,0 @@
-// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
-
-// deno-lint-ignore-file
-
-// This is a specialised implementation of a System module loader.
-
-"use strict";
-
-// @ts-nocheck
-var System, __instantiate;
-(function () {
-  // deno-fmt-ignore
-  var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
-    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
-    return new (P || (P = Promise))(function (resolve, reject) {
-        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
-        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
-        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
-        step((generator = generator.apply(thisArg, _arguments || [])).next());
-    });
-  };
-  // deno-fmt-ignore
-  var __generator = (this && this.__generator) || function (thisArg, body) {
-    var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
-    return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
-    function verb(n) { return function (v) { return step([n, v]); }; }
-    function step(op) {
-        if (f) throw new TypeError("Generator is already executing.");
-        while (_) try {
-            if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
-            if (y = 0, t) op = [op[0] & 2, t.value];
-            switch (op[0]) {
-                case 0: case 1: t = op; break;
-                case 4: _.label++; return { value: op[1], done: false };
-                case 5: _.label++; y = op[1]; op = [0]; continue;
-                case 7: op = _.ops.pop(); _.trys.pop(); continue;
-                default:
-                    if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
-                    if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
-                    if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
-                    if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
-                    if (t[2]) _.ops.pop();
-                    _.trys.pop(); continue;
-            }
-            op = body.call(thisArg, _);
-        } catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
-        if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
-    }
-  };
-  var r = Object.create(null);
-  System = {
-    register: function (id, d, f) {
-      r[id] = { d: d, f: f, exp: {} };
-    },
-  };
-  function dI(mid, src) {
-    return __awaiter(this, void 0, void 0, function () {
-      var id, _a, o, ia, _b, sa, oa, s, i;
-      return __generator(this, function (_c) {
-        id = mid.replace(/\.\w+$/i, "");
-        if (id.includes("./")) {
-          (_a = id.split("/").reverse()),
-            (o = _a[0]),
-            (ia = _a.slice(1)),
-            (_b = src.split("/").reverse()),
-            (sa = _b.slice(1)),
-            (oa = [o]);
-          (s = 0), (i = void 0);
-          while ((i = ia.shift())) {
-            if (i === "..") s++;
-            else if (i === ".") break;
-            else oa.push(i);
-          }
-          if (s < sa.length) oa.push.apply(oa, sa.slice(s));
-          id = oa.reverse().join("/");
-        }
-        return [
-          2,
-          id in r ? gExpA(id) : Promise.resolve().then(function () {
-            return require(mid);
-          }),
-        ];
-      });
-    });
-  }
-  function gC(id, main) {
-    return {
-      id: id,
-      import: function (m) {
-        return dI(m, id);
-      },
-      meta: { url: id, main: main },
-    };
-  }
-  function gE(exp) {
-    return function (id, v) {
-      var _a;
-      var e = typeof id === "string" ? ((_a = {}), (_a[id] = v), _a) : id;
-      for (var _i = 0, _b = Object.entries(e); _i < _b.length; _i++) {
-        var _c = _b[_i],
-          id_1 = _c[0],
-          value = _c[1];
-        Object.defineProperty(exp, id_1, {
-          value: value,
-          writable: true,
-          enumerable: true,
-        });
-      }
-      return v;
-    };
-  }
-  function rF(main) {
-    var m;
-    for (var id in r) {
-      m = r[id];
-      var f = m.f,
-        exp = m.exp;
-      var _a = f(gE(exp), gC(id, id === main)),
-        e = _a.execute,
-        s = _a.setters;
-      delete m.f;
-      m.e = e;
-      m.s = s;
-    }
-  }
-  function gExpA(id) {
-    return __awaiter(this, void 0, void 0, function () {
-      var m, d, e, s, i, _a, _b, r_1;
-      return __generator(this, function (_c) {
-        switch (_c.label) {
-          case 0:
-            if (!(id in r)) return [2];
-            m = r[id];
-            if (!m.s) return [3, 6];
-            (d = m.d), (e = m.e), (s = m.s);
-            delete m.s;
-            delete m.e;
-            i = 0;
-            _c.label = 1;
-          case 1:
-            if (!(i < s.length)) return [3, 4];
-            _b = (_a = s)[i];
-            return [4, gExpA(d[i])];
-          case 2:
-            _b.apply(_a, [_c.sent()]);
-            _c.label = 3;
-          case 3:
-            i++;
-            return [3, 1];
-          case 4:
-            r_1 = e();
-            if (!r_1) return [3, 6];
-            return [4, r_1];
-          case 5:
-            _c.sent();
-            _c.label = 6;
-          case 6:
-            return [2, m.exp];
-        }
-      });
-    });
-  }
-  function gExp(id) {
-    if (!(id in r)) return;
-    var m = r[id];
-    if (m.s) {
-      var d = m.d,
-        e = m.e,
-        s = m.s;
-      delete m.s;
-      delete m.e;
-      for (var i = 0; i < s.length; i++) s[i](gExp(d[i]));
-      e();
-    }
-    return m.exp;
-  }
-  __instantiate = function (m, a) {
-    System = __instantiate = undefined;
-    rF(m);
-    return a ? gExpA(m) : gExp(m);
-  };
-})();