diff --git a/README.md b/README.md
index e9e64673..80ec31be 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,16 @@ Add the `-s` option for server mode. This will allow you to view results in your
 | `--version` or `-v`     | Print version of software. |
 | `--format`              | Output format for CLI. Defaults to "human". Valid values are either "human" or "json". |
 
+### CLI Arguments
+
+Run `elm-analyse` with any number of extra source files to check following any flags.
+
+Example:
+
+``` shell
+$ elm-analyse --serve directory/not/in/source-directories/Main.elm other/Main.elm
+```
+
 ---
 
 ## Supported Checks
diff --git a/package-lock.json b/package-lock.json
index c5ad3c8a..94b22a5d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "elm-analyse",
-  "version": "0.16.3",
+  "version": "0.16.4",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -60,7 +60,7 @@
     "@types/express-ws": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/@types/express-ws/-/express-ws-3.0.0.tgz",
-      "integrity": "sha1-iWdO26LpFBkW/E1NMPvU+BDmuAs=",
+      "integrity": "sha512-GxsWec7Vp6h7sJuK0PwnZHeXNZnOwQn8kHAbCfvii66it5jXHTWzSg5cgHVtESwJfBLOe9SJ5wmM7C6gsDoyQw==",
       "dev": true,
       "requires": {
         "@types/express": "*",
@@ -334,7 +334,7 @@
     "aproba": {
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/aproba/-/aproba-1.2.0.tgz",
-      "integrity": "sha1-aALmJk79GMeQobDVF/DyYnvyyUo=",
+      "integrity": "sha512-Y9J6ZjXtoYh8RnXVCMOU/ttDmk1aBjunq9vO0ta5x85WDQiQfUF9sIPBITdbiiIVcBo03Hi3jMxigBtsddlXRw==",
       "dev": true
     },
     "archy": {
@@ -346,7 +346,7 @@
     "are-we-there-yet": {
       "version": "1.1.5",
       "resolved": "https://registry.npmjs.org/are-we-there-yet/-/are-we-there-yet-1.1.5.tgz",
-      "integrity": "sha1-SzXClE8GKov82mZBB2A1D+nd/CE=",
+      "integrity": "sha512-5hYdAkZlcG8tOLujVDTgCT+uPX0VnpAH28gWsLfzpXYm7wP6mp5Q/gYyR7YQ0cKVJcXJnl3j2kpBan13PtQf6w==",
       "dev": true,
       "requires": {
         "delegates": "^1.0.0",
@@ -490,7 +490,7 @@
     "asn1": {
       "version": "0.2.4",
       "resolved": "https://registry.npmjs.org/asn1/-/asn1-0.2.4.tgz",
-      "integrity": "sha1-jSR136tVO7M+d7VOWeiAu4ziMTY=",
+      "integrity": "sha512-jxwzQpLQjSmWXgwaCZE9Nz+glAG01yF1QnWgbhGwHI5A6FRIEY6IVqtHhIepHqI7/kyEyQEagBC5mBEFlIYvdg==",
       "requires": {
         "safer-buffer": "~2.1.0"
       }
@@ -726,7 +726,7 @@
     "bl": {
       "version": "1.2.2",
       "resolved": "https://registry.npmjs.org/bl/-/bl-1.2.2.tgz",
-      "integrity": "sha1-oWCRFxcQPAdBDO9j71Gzl8Alr5w=",
+      "integrity": "sha512-e8tQYnZodmebYDWGH7KMRvtzKXaJHx3BbilrgZCfvyLUYdKpK1t5PSPmpkny/SgiTSCnjfLW7v5rlONXVFkQEA==",
       "dev": true,
       "requires": {
         "readable-stream": "^2.3.5",
@@ -757,7 +757,7 @@
         "string_decoder": {
           "version": "1.1.1",
           "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
-          "integrity": "sha1-nPFhG6YmhdcDCunkujQUnDrwP8g=",
+          "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
           "dev": true,
           "requires": {
             "safe-buffer": "~5.1.0"
@@ -925,7 +925,7 @@
     "buffer-alloc": {
       "version": "1.2.0",
       "resolved": "https://registry.npmjs.org/buffer-alloc/-/buffer-alloc-1.2.0.tgz",
-      "integrity": "sha1-iQ3ZDZI6hz4I4Q5f1RpX5bfM4Ow=",
+      "integrity": "sha512-CFsHQgjtW1UChdXgbyJGtnm+O/uLQeZdtbDo8mfUgYXCHSM1wgrVxXm6bSyrUuErEb+4sYVGCzASBRot7zyrow==",
       "dev": true,
       "requires": {
         "buffer-alloc-unsafe": "^1.1.0",
@@ -935,7 +935,7 @@
     "buffer-alloc-unsafe": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/buffer-alloc-unsafe/-/buffer-alloc-unsafe-1.1.0.tgz",
-      "integrity": "sha1-vX3CauKXLQ7aJTvgYdupkjScGfA=",
+      "integrity": "sha512-TEM2iMIEQdJ2yjPJoSIsldnleVaAk1oW3DBVUykyOLsEsFmEc9kn+SFFPz+gl54KQNxlDnAwCXosOS9Okx2xAg==",
       "dev": true
     },
     "buffer-equal": {
@@ -963,14 +963,66 @@
       "dev": true
     },
     "bufferutil": {
-      "version": "3.0.3",
-      "resolved": "https://registry.npmjs.org/bufferutil/-/bufferutil-3.0.3.tgz",
-      "integrity": "sha1-zmfK794iglkeOZUoRn/mI/aPS9U=",
+      "version": "3.0.5",
+      "resolved": "https://registry.npmjs.org/bufferutil/-/bufferutil-3.0.5.tgz",
+      "integrity": "sha512-0fUEthLqfCkYspEuP0vmiAe+PsXslE+AlILb2rmS9I4tAdm3SmpCI69M66zQL20GQEszdbXyVN6q+cpG/yhYlg==",
       "dev": true,
       "requires": {
         "bindings": "~1.3.0",
-        "nan": "~2.7.0",
-        "prebuild-install": "~2.3.0"
+        "nan": "~2.10.0",
+        "prebuild-install": "~4.0.0"
+      },
+      "dependencies": {
+        "nan": {
+          "version": "2.10.0",
+          "resolved": "https://registry.npmjs.org/nan/-/nan-2.10.0.tgz",
+          "integrity": "sha512-bAdJv7fBLhWC+/Bls0Oza+mvTaNQtP+1RyhhhvD95pgUJz6XM5IzgmxOkItJ9tkoCiplvAnXI1tNmmUD/eScyA==",
+          "dev": true
+        },
+        "prebuild-install": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/prebuild-install/-/prebuild-install-4.0.0.tgz",
+          "integrity": "sha512-7tayxeYboJX0RbVzdnKyGl2vhQRWr6qfClEXDhOkXjuaOKCw2q8aiuFhONRYVsG/czia7KhpykIlI2S2VaPunA==",
+          "dev": true,
+          "requires": {
+            "detect-libc": "^1.0.3",
+            "expand-template": "^1.0.2",
+            "github-from-package": "0.0.0",
+            "minimist": "^1.2.0",
+            "mkdirp": "^0.5.1",
+            "node-abi": "^2.2.0",
+            "noop-logger": "^0.1.1",
+            "npmlog": "^4.0.1",
+            "os-homedir": "^1.0.1",
+            "pump": "^2.0.1",
+            "rc": "^1.1.6",
+            "simple-get": "^2.7.0",
+            "tar-fs": "^1.13.0",
+            "tunnel-agent": "^0.6.0",
+            "which-pm-runs": "^1.0.0"
+          }
+        },
+        "pump": {
+          "version": "2.0.1",
+          "resolved": "https://registry.npmjs.org/pump/-/pump-2.0.1.tgz",
+          "integrity": "sha512-ruPMNRkN3MHP1cWJc9OWr+T/xDP0jhXYCLfJcBuX54hhfIBnaQmAUMfDcG4DM5UMWByBbJY69QSphm3jtDKIkA==",
+          "dev": true,
+          "requires": {
+            "end-of-stream": "^1.1.0",
+            "once": "^1.3.1"
+          }
+        },
+        "simple-get": {
+          "version": "2.8.1",
+          "resolved": "https://registry.npmjs.org/simple-get/-/simple-get-2.8.1.tgz",
+          "integrity": "sha512-lSSHRSw3mQNUGPAYRqo7xy9dhKmxFXIjLjp4KHpf99GEH2VH7C3AM+Qfx6du6jhfUi6Vm7XnbEVEf7Wb6N8jRw==",
+          "dev": true,
+          "requires": {
+            "decompress-response": "^3.3.0",
+            "once": "^1.3.1",
+            "simple-concat": "^1.0.0"
+          }
+        }
       }
     },
     "builtin-modules": {
@@ -1132,7 +1184,8 @@
             "ansi-regex": {
               "version": "2.1.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "aproba": {
               "version": "1.2.0",
@@ -1153,12 +1206,14 @@
             "balanced-match": {
               "version": "1.0.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "brace-expansion": {
               "version": "1.1.11",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "balanced-match": "^1.0.0",
                 "concat-map": "0.0.1"
@@ -1173,17 +1228,20 @@
             "code-point-at": {
               "version": "1.1.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "concat-map": {
               "version": "0.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "console-control-strings": {
               "version": "1.1.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "core-util-is": {
               "version": "1.0.2",
@@ -1300,7 +1358,8 @@
             "inherits": {
               "version": "2.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "ini": {
               "version": "1.3.5",
@@ -1312,6 +1371,7 @@
               "version": "1.0.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "number-is-nan": "^1.0.0"
               }
@@ -1326,6 +1386,7 @@
               "version": "3.0.4",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "brace-expansion": "^1.1.7"
               }
@@ -1333,12 +1394,14 @@
             "minimist": {
               "version": "0.0.8",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "minipass": {
               "version": "2.3.5",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "safe-buffer": "^5.1.2",
                 "yallist": "^3.0.0"
@@ -1357,6 +1420,7 @@
               "version": "0.5.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "minimist": "0.0.8"
               }
@@ -1437,7 +1501,8 @@
             "number-is-nan": {
               "version": "1.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "object-assign": {
               "version": "4.1.1",
@@ -1449,6 +1514,7 @@
               "version": "1.4.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "wrappy": "1"
               }
@@ -1534,7 +1600,8 @@
             "safe-buffer": {
               "version": "5.1.2",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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               "version": "2.1.2",
@@ -1570,6 +1637,7 @@
               "version": "1.0.2",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "code-point-at": "^1.0.0",
                 "is-fullwidth-code-point": "^1.0.0",
@@ -1589,6 +1657,7 @@
               "version": "3.0.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "ansi-regex": "^2.0.0"
               }
@@ -1632,12 +1701,14 @@
             "wrappy": {
               "version": "1.0.2",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "yallist": {
               "version": "3.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -1927,7 +1998,8 @@
             "ansi-regex": {
               "version": "2.1.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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               "version": "1.2.0",
@@ -1948,12 +2020,14 @@
             "balanced-match": {
               "version": "1.0.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "brace-expansion": {
               "version": "1.1.11",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
                 "balanced-match": "^1.0.0",
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@@ -1968,17 +2042,20 @@
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               "version": "1.1.0",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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               "version": "0.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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               "version": "1.1.0",
               "bundled": true,
-              "dev": true
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@@ -2095,7 +2172,8 @@
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               "version": "2.0.3",
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-              "dev": true
+              "dev": true,
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@@ -2107,6 +2185,7 @@
               "version": "1.0.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -2121,6 +2200,7 @@
               "version": "3.0.4",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -2128,12 +2208,14 @@
             "minimist": {
               "version": "0.0.8",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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             "minipass": {
               "version": "2.3.5",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -2152,6 +2234,7 @@
               "version": "0.5.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -2232,7 +2315,8 @@
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               "version": "1.0.1",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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               "version": "4.1.1",
@@ -2244,6 +2328,7 @@
               "version": "1.4.0",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
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@@ -2329,7 +2414,8 @@
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               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -2365,6 +2451,7 @@
               "version": "1.0.2",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -2384,6 +2471,7 @@
               "version": "3.0.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
               "requires": {
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@@ -2427,12 +2515,14 @@
             "wrappy": {
               "version": "1.0.2",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
             },
             "yallist": {
               "version": "3.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -2981,10 +3071,19 @@
       "integrity": "sha1-6zkTMzRYd1y4TNGh+uBiEGu4dUU=",
       "dev": true
     },
+    "decompress-response": {
+      "version": "3.3.0",
+      "resolved": "https://registry.npmjs.org/decompress-response/-/decompress-response-3.3.0.tgz",
+      "integrity": "sha1-gKTdMjdIOEv6JICDYirt7Jgq3/M=",
+      "dev": true,
+      "requires": {
+        "mimic-response": "^1.0.0"
+      }
+    },
     "deep-extend": {
       "version": "0.6.0",
       "resolved": "https://registry.npmjs.org/deep-extend/-/deep-extend-0.6.0.tgz",
-      "integrity": "sha1-xPp8lUBKF6nD6Mp+FTcxK3NjMKw=",
+      "integrity": "sha512-LOHxIOaPYdHlJRtCQfDIVZtfw/ufM8+rVj649RIHzcm/vGwQRXFt6OPqIFWsm2XEMrNIEtWR64sY1LEKD2vAOA==",
       "dev": true
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@@ -3105,6 +3204,12 @@
       "integrity": "sha1-8NZtA2cqglyxtzvbP+YjEMjlUrc=",
       "dev": true
     },
+    "detect-libc": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/detect-libc/-/detect-libc-1.0.3.tgz",
+      "integrity": "sha1-+hN8S9aY7fVc1c0CrFWfkaTEups=",
+      "dev": true
+    },
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@@ -3766,7 +3871,7 @@
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-      "integrity": "sha1-mB8YjAw6h9Lij1WbxUFCb/lPId0=",
+      "integrity": "sha512-cebqLtV8KOZfw0UI8TEFWxtczxxC1jvyUvx6H4fyp1K1FN7A4Q+uggVUlOsI1K8AGU0rwOGqP8nCapdrw8CYQg==",
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@@ -3837,7 +3942,7 @@
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       "resolved": "https://registry.npmjs.org/extend/-/extend-3.0.2.tgz",
-      "integrity": "sha1-+LETa0Bx+9jrFAr/hYsQGewpFfo="
+      "integrity": "sha512-fjquC59cD7CyW6urNXK0FBufkZcoiGG80wTuPujX590cB5Ttln20E2UB4S/WARVqhXffZl2LNgS+gQdPIIim/g=="
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@@ -4454,7 +4559,7 @@
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-      "integrity": "sha1-3M5SwF9kTymManq5Nr1yTO/786Y=",
+      "integrity": "sha512-1lLKB2Mu3aGP1Q/2eCOx0fNbRMe7XdwktwOruhfqqd0rIJWwN4Dh+E3hrPSlDCXnSR7UtZ1N38rVXm+6+MEhJQ==",
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@@ -4483,7 +4588,7 @@
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-      "integrity": "sha1-a+Dem+mYzhavivwkSXue6bfM2a0=",
+      "integrity": "sha512-y6OAwoSIf7FyjMIv94u+b5rdheZEjzR63GTyZJm5qh4Bi+2YgwLCcI/fPFZkL5PSixOt6ZNKm+w+Hfp/Bciwow==",
       "dev": true
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@@ -4575,7 +4680,8 @@
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           "integrity": "sha1-w7M6te42DYbg5ijwRorn7yfWVN8=",
-          "dev": true
+          "dev": true,
+          "optional": true
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         "aproba": {
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@@ -4599,13 +4705,15 @@
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           "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "brace-expansion": {
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@@ -7406,6 +7530,12 @@
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+    "mimic-response": {
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@@ -7632,6 +7756,12 @@
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@@ -7943,7 +8073,8 @@
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@@ -7964,12 +8095,14 @@
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               "version": "1.1.11",
               "bundled": true,
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@@ -7984,17 +8117,20 @@
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+              "optional": true
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               "version": "0.0.1",
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-              "dev": true
+              "dev": true,
+              "optional": true
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-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -8111,7 +8247,8 @@
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               "version": "2.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -8123,6 +8260,7 @@
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               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -8137,6 +8275,7 @@
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               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -8144,12 +8283,14 @@
             "minimist": {
               "version": "0.0.8",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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             "minipass": {
               "version": "2.3.5",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -8168,6 +8309,7 @@
               "version": "0.5.1",
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               "dev": true,
+              "optional": true,
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@@ -8248,7 +8390,8 @@
             "number-is-nan": {
               "version": "1.0.1",
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-              "dev": true
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+              "optional": true
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@@ -8260,6 +8403,7 @@
               "version": "1.4.0",
               "bundled": true,
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+              "optional": true,
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@@ -8345,7 +8489,8 @@
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+              "optional": true
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@@ -8381,6 +8526,7 @@
               "version": "1.0.2",
               "bundled": true,
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+              "optional": true,
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@@ -8400,6 +8546,7 @@
               "version": "3.0.1",
               "bundled": true,
               "dev": true,
+              "optional": true,
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@@ -8443,12 +8590,14 @@
             "wrappy": {
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               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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             "yallist": {
               "version": "3.0.3",
               "bundled": true,
-              "dev": true
+              "dev": true,
+              "optional": true
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@@ -8657,7 +8806,7 @@
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-      "integrity": "sha1-CKfyqL9zRgR3mp76StXMcXq7lUs=",
+      "integrity": "sha512-2uUqazuKlTaSI/dC8AzicUck7+IrEaOnN/e0jd3Xtt1KcGpwx30v50mL7oPyr/h9bL3E4aZccVwpwP+5W9Vjkg==",
       "dev": true,
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@@ -9133,28 +9282,6 @@
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       "dev": true
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-      "resolved": "https://registry.npmjs.org/prebuild-install/-/prebuild-install-2.3.0.tgz",
-      "integrity": "sha1-GUgSR99yi4VKtXsYfOI0IRMRtIU=",
-      "dev": true,
-      "requires": {
-        "expand-template": "^1.0.2",
-        "github-from-package": "0.0.0",
-        "minimist": "^1.2.0",
-        "mkdirp": "^0.5.1",
-        "node-abi": "^2.1.1",
-        "noop-logger": "^0.1.1",
-        "npmlog": "^4.0.1",
-        "os-homedir": "^1.0.1",
-        "pump": "^1.0.1",
-        "rc": "^1.1.6",
-        "simple-get": "^1.4.2",
-        "tar-fs": "^1.13.0",
-        "tunnel-agent": "^0.6.0",
-        "xtend": "4.0.1"
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     "prelude-ls": {
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       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.1.2.tgz",
@@ -9333,7 +9460,7 @@
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-      "integrity": "sha1-zZJL9SAKB1uDwYjNa54hG3/A0+0=",
+      "integrity": "sha512-y3bGgqKj3QBdxLbLkomlohkvsA8gdAiUQlSBJnBhfn+BPxg4bc62d8TcBW15wavDfgexCgccckhcZvywyQYPOw==",
       "dev": true,
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@@ -10146,16 +10273,11 @@
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       "dev": true
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-    "simple-get": {
-      "version": "1.4.3",
-      "resolved": "https://registry.npmjs.org/simple-get/-/simple-get-1.4.3.tgz",
-      "integrity": "sha1-6XVe2kB+ltpAxeUVjJ6jezO+y+s=",
-      "dev": true,
-      "requires": {
-        "once": "^1.3.1",
-        "unzip-response": "^1.0.0",
-        "xtend": "^4.0.0"
-      }
+    "simple-concat": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/simple-concat/-/simple-concat-1.0.1.tgz",
+      "integrity": "sha512-cSFtAPtRhljv69IK0hTVZQ+OfE9nePi/rtJmw5UjHeVyVroEqJXP1sFztKUy1qU+xvz3u/sfYJLa947b7nAN2Q==",
+      "dev": true
     },
     "slice-ansi": {
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@@ -10661,7 +10783,7 @@
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       "resolved": "https://registry.npmjs.org/tar-fs/-/tar-fs-1.16.3.tgz",
-      "integrity": "sha1-lmpiiEHaLEAQQGqCFny9Xgxy1Qk=",
+      "integrity": "sha512-NvCeXpYx7OsmOh8zIOP/ebG55zZmxLE0etfWRbWok+q2Qo8x/vOR/IJT1taADXPe+jsiu9axDb3X4B+iIgNlKw==",
       "dev": true,
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@@ -10673,7 +10795,7 @@
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       "resolved": "https://registry.npmjs.org/tar-stream/-/tar-stream-1.6.2.tgz",
-      "integrity": "sha1-jqVdqzeXIlPZqa+Q/c1VmuQ1xVU=",
+      "integrity": "sha512-rzS0heiNf8Xn7/mpdSVVSMAWAoy9bfb1WOTYC78Z0UQKeKa/CWS8FOq0lKGNa8DWKAn9gxjCvMLYc5PGXYlK2A==",
       "dev": true,
       "requires": {
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@@ -10709,7 +10831,7 @@
         "string_decoder": {
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           "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-1.1.1.tgz",
-          "integrity": "sha1-nPFhG6YmhdcDCunkujQUnDrwP8g=",
+          "integrity": "sha512-n/ShnvDi6FHbbVfviro+WojiFzv+s8MPMHBczVePfUpDJLwoLT0ht1l4YwBCbi8pJAveEEdnkHyPyTP/mzRfwg==",
           "dev": true,
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@@ -10837,7 +10959,7 @@
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       "resolved": "https://registry.npmjs.org/to-buffer/-/to-buffer-1.1.1.tgz",
-      "integrity": "sha1-STvUj2LXxD/N7TE6A9ytsuEhOoA=",
+      "integrity": "sha512-lx9B5iv7msuFYE3dytT+KE5tap+rNYw+K4jVkb9R/asAb+pbBSM17jtunHplhBe6RRJdZx3Pn2Jph24O32mOVg==",
       "dev": true
     },
     "to-object-path": {
@@ -11207,12 +11329,6 @@
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       }
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-    "unzip-response": {
-      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/unzip-response/-/unzip-response-1.0.2.tgz",
-      "integrity": "sha1-uYTwh3/AqJwsdzzB73tbIytbBv4=",
-      "dev": true
-    },
     "unzip-stream": {
       "version": "0.3.0",
       "resolved": "https://registry.npmjs.org/unzip-stream/-/unzip-stream-0.3.0.tgz",
@@ -11312,14 +11428,12 @@
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-      "version": "3.0.4",
-      "resolved": "https://registry.npmjs.org/utf-8-validate/-/utf-8-validate-3.0.4.tgz",
-      "integrity": "sha1-p5liz6QULdpwUCNOfps3szkH0q8=",
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/utf-8-validate/-/utf-8-validate-5.0.2.tgz",
+      "integrity": "sha512-SwV++i2gTD5qh2XqaPzBnNX88N6HdyhQrNNRykvcS0QKvItV9u3vPEJr+X5Hhfb1JC0r0e1alL0iB09rY8+nmw==",
       "dev": true,
       "requires": {
-        "bindings": "~1.3.0",
-        "nan": "~2.7.0",
-        "prebuild-install": "~2.3.0"
+        "node-gyp-build": "~3.7.0"
       }
     },
     "util-deprecate": {
@@ -11541,10 +11655,16 @@
       "integrity": "sha1-2e8H3Od7mQK4o6j6SzHD4/fm6Ho=",
       "dev": true
     },
+    "which-pm-runs": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/which-pm-runs/-/which-pm-runs-1.0.0.tgz",
+      "integrity": "sha1-Zws6+8VS4LVd9rd4DKdGFfI60cs=",
+      "dev": true
+    },
     "wide-align": {
       "version": "1.1.3",
       "resolved": "https://registry.npmjs.org/wide-align/-/wide-align-1.1.3.tgz",
-      "integrity": "sha1-rgdOa9wMFKQx6ATmJFScYzsABFc=",
+      "integrity": "sha512-QGkOQc8XL6Bt5PwnsExKBPuMKBxnGxWWW3fU55Xt4feHozMUhdUMaBCk290qpm/wG5u/RSKzwdAC4i51YigihA==",
       "dev": true,
       "requires": {
         "string-width": "^1.0.2 || 2"
diff --git a/package.json b/package.json
index 98f086eb..53cb408d 100644
--- a/package.json
+++ b/package.json
@@ -56,7 +56,7 @@
     "@types/request": "^2.47.1",
     "@types/ws": "^5.1.2",
     "bootstrap": "^3.4.1",
-    "bufferutil": "3.0.3",
+    "bufferutil": "3.0.5",
     "chokidar": "^2.1.2",
     "chokidar-cli": "^1.2.2",
     "elm": "0.19.0-bugfix2",
@@ -72,6 +72,6 @@
     "run-sequence": "1.2.2",
     "sb-admin-2": "^3.3.8",
     "typescript": "^2.9.2",
-    "utf-8-validate": "3.0.4"
+    "utf-8-validate": "5.0.2"
   }
 }
diff --git a/ts/bin/index.ts b/ts/bin/index.ts
index 724d3d70..e74f7eb2 100755
--- a/ts/bin/index.ts
+++ b/ts/bin/index.ts
@@ -29,7 +29,8 @@ var args = minimist(process.argv.slice(2), {
         port: args.port || 3000,
         elmFormatPath: elmFormatPath,
         format: validFormats.indexOf(args.format) != -1 ? args.format : 'human',
-        open: args.open || false
+        open: args.open || false,
+        extraSourcePaths: args._
     };
     const info = {
         version: elmAnalyseVersion,
@@ -39,9 +40,9 @@ var args = minimist(process.argv.slice(2), {
 
     if (args.help) {
         console.log('Usages:');
-        console.log('  $ elm-analyse');
+        console.log('  $ elm-analyse [PATHS ...]');
         console.log('    # Analyse the project and log messages to the console\n');
-        console.log('  $ elm-analyse -s');
+        console.log('  $ elm-analyse -s [PATHS ...]');
         console.log(
             '    # Analyse the project and start a server. Allows inspection of messages through a browser (Default: http://localhost:3000).\n'
         );
@@ -52,6 +53,8 @@ var args = minimist(process.argv.slice(2), {
         console.log('   --open, -o          Open default browser when server goes live.');
         console.log('   --elm-format-path   Path to elm-format. Defaults to `elm-format`.');
         console.log('   --format            Output format for CLI. Defaults to "human". Options "human"|"json"');
+        console.log('Arguments: ');
+        console.log('   PATHS               Optional extra source paths. Example: Main.elm');
         process.exit(1);
     }
 
diff --git a/ts/domain.ts b/ts/domain.ts
index 3c673cca..5528f1c9 100644
--- a/ts/domain.ts
+++ b/ts/domain.ts
@@ -6,6 +6,7 @@ interface Config {
     open: boolean;
     port: number;
     elmFormatPath: string;
+    extraSourcePaths: string[];
 }
 
 export interface DependencyPointer {
diff --git a/ts/file-loading-ports.ts b/ts/file-loading-ports.ts
index 782d1101..61d3cf32 100644
--- a/ts/file-loading-ports.ts
+++ b/ts/file-loading-ports.ts
@@ -16,5 +16,5 @@ export function setup(app: ElmApp, config: Config, directory: string): void {
     RawDependencies.setup(app);
     DependencyFiles.setup(app, directory, fileReader);
     FileLoader.setup(app, config, directory, localCache, fileReader);
-    Context.setup(app, directory);
+    Context.setup(config, app, directory);
 }
diff --git a/ts/ports/context.ts b/ts/ports/context.ts
index e170d405..6fc8e2b2 100644
--- a/ts/ports/context.ts
+++ b/ts/ports/context.ts
@@ -1,10 +1,10 @@
 import * as fs from 'fs';
 import * as fileGatherer from '../util/file-gatherer';
-import { ElmApp, Context } from '../domain';
+import { Config, ElmApp, Context } from '../domain';
 
-function setup(app: ElmApp, directory: string) {
+function setup(config: Config, app: ElmApp, directory: string) {
     app.ports.loadContext.subscribe(() => {
-        const input = fileGatherer.gather(directory);
+        const input = fileGatherer.gather(config, directory);
         var configuration;
         try {
             configuration = fs.readFileSync('./elm-analyse.json').toString();
diff --git a/ts/server/app.ts b/ts/server/app.ts
index bce99389..5a80db7e 100644
--- a/ts/server/app.ts
+++ b/ts/server/app.ts
@@ -39,7 +39,7 @@ function start(config: Config, info: Info, project: {}) {
 
         app.get('/api/tree', function(_req, res) {
             const directory = process.cwd();
-            const x = fileGatherer.gather(directory);
+            const x = fileGatherer.gather(config, directory);
             res.send(x.sourceFiles);
         });
 
diff --git a/ts/util/file-gatherer.ts b/ts/util/file-gatherer.ts
index cccf806e..091f3501 100644
--- a/ts/util/file-gatherer.ts
+++ b/ts/util/file-gatherer.ts
@@ -2,7 +2,7 @@ import * as fs from 'fs';
 import _ from 'lodash';
 import * as find from 'find';
 import * as _path from 'path';
-import { DependencyPointer } from '../domain';
+import { Config, DependencyPointer } from '../domain';
 
 function isRealElmPaths(sourceDir: string, filePath: String): boolean {
     const modulePath = filePath.replace(_path.normalize(sourceDir + '/'), '');
@@ -76,12 +76,13 @@ function getDependencyFiles(directory: string, dep: DependencyPointer) {
     });
 }
 
-function gather(directory: string): { interfaceFiles: Array<string[]>; sourceFiles: string[] } {
+function gather(config: Config, directory: string): { interfaceFiles: Array<string[]>; sourceFiles: string[] } {
     const packageFile = require(directory + '/elm.json');
 
     const input = {
         interfaceFiles: [],
         sourceFiles: targetFilesForPathAndPackage(directory, directory, packageFile)
+            .concat(_.uniq(config.extraSourcePaths))
     };
     return input;
 }