diff --git a/.gitignore b/.gitignore
index 3bd6c94..adee2aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,6 +2,7 @@
 /esm
 /index.d.ts
 /index.js
+/index.js.flow
 /node_modules
 /test.js
 /umd
diff --git a/index.js.flow b/index.js.flow
deleted file mode 100644
index 53ef5db..0000000
--- a/index.js.flow
+++ /dev/null
@@ -1,19 +0,0 @@
-// @flow
-
-declare export type Graph = {
-    size: number;
-    adjacencyMatrix: Array<Array<number>>;
-};
-declare export type D3Graph = {
-    nodes: Array<{
-        id: string;
-    }>;
-    links: Array<{
-        source: string;
-        target: string;
-    }>;
-};
-declare export function toD3(graph: Graph): D3Graph;
-declare export function fromD3(graph: D3Graph): Graph;
-declare export function isCyclic(graph: Graph): boolean;
-declare export function topologicalSort(graph: Graph): Array<number>;
diff --git a/package.json b/package.json
index f822f41..efb1b34 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
   },
   "scripts": {
     "build": "yarn build:declaration && yarn build:cjs && yarn build:umd && yarn build:esm",
-    "build:declaration": "tsc index.ts --downlevelIteration --declaration --emitDeclarationOnly",
+    "build:declaration": "tsc index.ts --downlevelIteration --declaration --emitDeclarationOnly && flowgen index.d.ts -o index.js.flow",
     "build:cjs": "tsc index.ts --downlevelIteration --target ES2015 --module CommonJS --outDir cjs",
     "build:umd": "tsc index.ts --downlevelIteration --target ES2015 --module UMD --outDir umd",
     "build:esm": "tsc index.ts --target ESNext --module ESNext --outDir esm",
@@ -37,6 +37,7 @@
   "devDependencies": {
     "@types/node": "^14.14.12",
     "@types/tape": "^4.13.0",
+    "flowgen": "^1.13.0",
     "np": "^7.0.0",
     "tape": "^5.0.1",
     "typescript": "^4.1.3"
diff --git a/yarn.lock b/yarn.lock
index 3ad946e..8555552 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -9,6 +9,13 @@
   dependencies:
     "@babel/highlight" "^7.10.4"
 
+"@babel/code-frame@^7.10.4":
+  version "7.12.11"
+  resolved "https://registry.yarnpkg.com/@babel/code-frame/-/code-frame-7.12.11.tgz#f4ad435aa263db935b8f10f2c552d23fb716a63f"
+  integrity sha512-Zt1yodBx1UcyiePMSkWnU4hPqhwq7hGi2nFL1LeA3EUl+q2LQx16MISgJ0+z7dnmgvP9QtIleuETGOiOH1RcIw==
+  dependencies:
+    "@babel/highlight" "^7.10.4"
+
 "@babel/helper-validator-identifier@^7.10.4":
   version "7.10.4"
   resolved "https://registry.yarnpkg.com/@babel/helper-validator-identifier/-/helper-validator-identifier-7.10.4.tgz#a78c7a7251e01f616512d31b10adcf52ada5e0d2"
@@ -458,6 +465,11 @@ color-name@~1.1.4:
   resolved "https://registry.yarnpkg.com/color-name/-/color-name-1.1.4.tgz#c2a09a87acbde69543de6f63fa3995c826c536a2"
   integrity sha512-dOy+3AuW3a2wNbZHIuMZpTcgjGuLU/uBL/ubcZF9OXbDo8ff4O8yVp5Bf0efS8uEoYo5q4Fx7dY9OgQGXgAsQA==
 
+commander@^6.1.0:
+  version "6.2.1"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-6.2.1.tgz#0792eb682dfbc325999bb2b84fddddba110ac73c"
+  integrity sha512-U7VdrJFnJgo4xjrHpTzu0yrHPGImdsmD95ZlgYSEajAn2JKzDhDTPG9kBTefmObL2w/ngeZnilk+OV9CG3d7UA==
+
 concat-map@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
@@ -815,6 +827,20 @@ find-up@^5.0.0:
     locate-path "^6.0.0"
     path-exists "^4.0.0"
 
+flowgen@^1.13.0:
+  version "1.13.0"
+  resolved "https://registry.yarnpkg.com/flowgen/-/flowgen-1.13.0.tgz#c20319442cd2800a43a0fb625f6dec5d3d2b9add"
+  integrity sha512-xgdbeWfhY5yayQ3PUTaPn9a0tPK21m5SEJSFZDZf0A0TuoLKYVXU3fhhAN9pokjDcb0E0FGh7EO3t3YNf/iXTw==
+  dependencies:
+    "@babel/code-frame" "^7.10.4"
+    "@babel/highlight" "^7.10.4"
+    commander "^6.1.0"
+    lodash "^4.17.20"
+    prettier "^2.1.1"
+    shelljs "^0.8.4"
+    typescript "^4.0.2"
+    typescript-compiler "^1.4.1-2"
+
 for-each@^0.3.3:
   version "0.3.3"
   resolved "https://registry.yarnpkg.com/for-each/-/for-each-0.3.3.tgz#69b447e88a0a5d32c3e7084f3f1710034b21376e"
@@ -872,7 +898,7 @@ glob-parent@^5.1.0:
   dependencies:
     is-glob "^4.0.1"
 
-glob@^7.1.3, glob@^7.1.6:
+glob@^7.0.0, glob@^7.1.3, glob@^7.1.6:
   version "7.1.6"
   resolved "https://registry.yarnpkg.com/glob/-/glob-7.1.6.tgz#141f33b81a7c2492e125594307480c46679278a6"
   integrity sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==
@@ -1127,6 +1153,11 @@ inquirer@^7.0.0, inquirer@^7.3.3:
     strip-ansi "^6.0.0"
     through "^2.3.6"
 
+interpret@^1.0.0:
+  version "1.4.0"
+  resolved "https://registry.yarnpkg.com/interpret/-/interpret-1.4.0.tgz#665ab8bc4da27a774a40584e812e3e0fa45b1a1e"
+  integrity sha512-agE4QfB2Lkp9uICn7BAqoscw4SZP9kTE2hxiFI3jBPmXJfdqiahTbUuKGsMoN2GtqL9AxhYioAcVvgsb1HvRbA==
+
 is-arguments@^1.0.4:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/is-arguments/-/is-arguments-1.1.0.tgz#62353031dfbee07ceb34656a6bde59efecae8dd9"
@@ -1497,7 +1528,7 @@ lodash.zip@^4.2.0:
   resolved "https://registry.yarnpkg.com/lodash.zip/-/lodash.zip-4.2.0.tgz#ec6662e4896408ed4ab6c542a3990b72cc080020"
   integrity sha1-7GZi5IlkCO1KtsVCo5kLcswIACA=
 
-lodash@^4.17.12, lodash@^4.17.19:
+lodash@^4.17.12, lodash@^4.17.19, lodash@^4.17.20:
   version "4.17.20"
   resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.17.20.tgz#b44a9b6297bcb698f1c51a3545a2b3b368d59c52"
   integrity sha512-PlhdFcillOINfeV7Ni6oF1TAEayyZBoZ8bcshTHqOYJYlrqzRK5hagpagky5o4HfCzzd1TRkXPMFq6cKk9rGmA==
@@ -2022,6 +2053,11 @@ prepend-http@^2.0.0:
   resolved "https://registry.yarnpkg.com/prepend-http/-/prepend-http-2.0.0.tgz#e92434bfa5ea8c19f41cdfd401d741a3c819d897"
   integrity sha1-6SQ0v6XqjBn0HN/UAddBo8gZ2Jc=
 
+prettier@^2.1.1:
+  version "2.2.1"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-2.2.1.tgz#795a1a78dd52f073da0cd42b21f9c91381923ff5"
+  integrity sha512-PqyhM2yCjg/oKkFPtTGUojv7gnZAoG80ttl45O6x2Ug/rMJw4wcc9k6aaf2hibP7BGVCCM33gZoGjyvt9mm16Q==
+
 pump@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/pump/-/pump-3.0.0.tgz#b4a2116815bde2f4e1ea602354e8c75565107a64"
@@ -2071,6 +2107,13 @@ read-pkg@^5.2.0:
     parse-json "^5.0.0"
     type-fest "^0.6.0"
 
+rechoir@^0.6.2:
+  version "0.6.2"
+  resolved "https://registry.yarnpkg.com/rechoir/-/rechoir-0.6.2.tgz#85204b54dba82d5742e28c96756ef43af50e3384"
+  integrity sha1-hSBLVNuoLVdC4oyWdW70OvUOM4Q=
+  dependencies:
+    resolve "^1.1.6"
+
 redent@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/redent/-/redent-3.0.0.tgz#e557b7998316bb53c9f1f56fa626352c6963059f"
@@ -2118,7 +2161,7 @@ resolve-from@^5.0.0:
   resolved "https://registry.yarnpkg.com/resolve-from/-/resolve-from-5.0.0.tgz#c35225843df8f776df21c57557bc087e9dfdfc69"
   integrity sha512-qYg9KP24dD5qka9J47d0aVky0N+b4fTU89LN9iDnjB5waksiC49rvMB0PrUJQGoTmH50XPiqOvAjDfaijGxYZw==
 
-resolve@^1.10.0, resolve@^1.17.0:
+resolve@^1.1.6, resolve@^1.10.0, resolve@^1.17.0:
   version "1.19.0"
   resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.19.0.tgz#1af5bf630409734a067cae29318aac7fa29a267c"
   integrity sha512-rArEXAgsBG4UgRGcynxWIWKFvh/XZCcS8UJdHhwy91zwAvCZIbcs+vAbflgBnNjYMs/i/i+/Ux6IZhML1yPvxg==
@@ -2238,6 +2281,15 @@ shebang-regex@^3.0.0:
   resolved "https://registry.yarnpkg.com/shebang-regex/-/shebang-regex-3.0.0.tgz#ae16f1644d873ecad843b0307b143362d4c42172"
   integrity sha512-7++dFhtcx3353uBaq8DDR4NuxBetBzC7ZQOhmTQInHEd6bSrXdiEyzCvG07Z44UYdLShWUyXt5M/yhz8ekcb1A==
 
+shelljs@^0.8.4:
+  version "0.8.4"
+  resolved "https://registry.yarnpkg.com/shelljs/-/shelljs-0.8.4.tgz#de7684feeb767f8716b326078a8a00875890e3c2"
+  integrity sha512-7gk3UZ9kOfPLIAbslLzyWeGiEqx9e3rxwZM0KE6EL8GlGwjym9Mrlx5/p33bWTu9YG6vcS4MBxYZDHYr5lr8BQ==
+  dependencies:
+    glob "^7.0.0"
+    interpret "^1.0.0"
+    rechoir "^0.6.2"
+
 side-channel@^1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/side-channel/-/side-channel-1.0.3.tgz#cdc46b057550bbab63706210838df5d4c19519c3"
@@ -2553,7 +2605,12 @@ typedarray-to-buffer@^3.1.5:
   dependencies:
     is-typedarray "^1.0.0"
 
-typescript@^4.1.3:
+typescript-compiler@^1.4.1-2:
+  version "1.4.1-2"
+  resolved "https://registry.yarnpkg.com/typescript-compiler/-/typescript-compiler-1.4.1-2.tgz#ba4f7db22d91534a1929d90009dce161eb72fd3f"
+  integrity sha1-uk99si2RU0oZKdkACdzhYety/T8=
+
+typescript@^4.0.2, typescript@^4.1.3:
   version "4.1.3"
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.1.3.tgz#519d582bd94cba0cf8934c7d8e8467e473f53bb7"
   integrity sha512-B3ZIOf1IKeH2ixgHhj6la6xdwR9QrLC5d1VKeCSY4tvkqhF2eqd9O7txNlS0PO3GrBAFIdr3L1ndNwteUbZLYg==