diff --git a/cli/package.json b/cli/package.json
index ea354b12f0..251048b61b 100644
--- a/cli/package.json
+++ b/cli/package.json
@@ -36,9 +36,9 @@
     "semver": "^5.5.0",
     "table": "^4.0.2",
     "through": "^2.3.8",
-    "unzipper": "^0.8.11",
     "which": "^1.3.0",
-    "yargs": "^4.2.0"
+    "yargs": "^4.2.0",
+    "yauzl-promise": "^2.1.2"
   },
   "devDependencies": {
     "babel-cli": "^6.26.0",
diff --git a/cli/src/commands/runTests.js b/cli/src/commands/runTests.js
index 4af1cf3df3..53f49c8ec3 100644
--- a/cli/src/commands/runTests.js
+++ b/cli/src/commands/runTests.js
@@ -1,16 +1,14 @@
 // @flow
 
-import {child_process, fs, os, path} from '../lib/node.js';
+import {fs, path} from '../lib/node.js';
 import {copyFile, recursiveRmdir} from '../lib/fileUtils.js';
-import {gitHubClient} from '../lib/github.js';
 import {getLibDefs, parseRepoDirItem} from '../lib/libDefs.js';
 import isInFlowTypedRepo from '../lib/isInFlowTypedRepo';
 import {toSemverString as flowVerToSemverString} from '../lib/flowVersion';
 import {getDiff} from '../lib/git';
+import {getFlowBinaries, type Flow} from '../lib/binaries';
 
-import got from 'got';
 import * as semver from 'semver';
-import * as unzip from 'unzipper';
 import typeof Yargs from 'yargs';
 import type {FlowVersion} from '../lib/flowVersion.js';
 
@@ -21,24 +19,10 @@ export type Args = {
   numberOfFlowVersions?: number,
 };
 
-// Used to decide which binary to fetch for each version of Flow
-const BIN_PLATFORM = (_ => {
-  switch (os.type()) {
-    case 'Linux':
-      return 'linux64';
-    case 'Darwin':
-      return 'osx';
-    case 'Windows_NT':
-      return 'win64';
-
-    default:
-      throw new Error('Unsupported os.type()! ' + os.type());
-  }
-})();
 const PKG_ROOT_DIR = path.join(__dirname, '..', '..');
 const TEST_DIR = path.join(PKG_ROOT_DIR, '.test-dir');
 const BIN_DIR = path.join(PKG_ROOT_DIR, '.flow-bins-cache');
-const P = Promise;
+const NUMBER_OF_FLOW_VERSIONS = 15;
 
 type TestGroup = {
   id: string,
@@ -86,203 +70,6 @@ async function getTestGroups(
   });
 }
 
-/**
- * Memoized function that queries the GitHub releases for Flow, downloads the
- * zip for each version, extracts the zip, and moves the binary to
- * TEST_BIN/flow-vXXX for use later when running tests.
- */
-let _flowBinVersionPromise = null;
-async function getOrderedFlowBinVersions(
-  numberOfReleases: number = 15,
-): Promise<Array<string>> {
-  if (_flowBinVersionPromise !== null) {
-    return _flowBinVersionPromise;
-  }
-  return (_flowBinVersionPromise = (async function() {
-    console.log('Fetching all Flow binaries...');
-    const IS_WINDOWS = os.type() === 'Windows_NT';
-    const GH_CLIENT = gitHubClient();
-    // We only test against the latest numberOfReleases Versions
-    const QUERY_PAGE_SIZE = numberOfReleases;
-    const OS_ARCH_FILTER_RE = new RegExp(`flow-${BIN_PLATFORM}`);
-
-    let page = 0;
-    const apiPayload = await GH_CLIENT.repos.getReleases({
-      owner: 'facebook',
-      repo: 'flow',
-      page: page++,
-      per_page: QUERY_PAGE_SIZE,
-    });
-
-    const flowBins = apiPayload.data
-      .filter(rel => {
-        // Temporary fix for https://github.com/facebook/flow/issues/5922
-        if (rel.tag_name === 'v0.67.0') {
-          console.log(
-            '==========================================================================================',
-          );
-          console.log(
-            'We are tempoarily skipping v0.67.0 due to https://github.com/facebook/flow/issues/5922',
-          );
-          console.log(
-            '==========================================================================================',
-          );
-          return false;
-        }
-
-        // We only test against versions since 0.15.0 because it has proper
-        // [ignore] fixes (which are necessary to run tests)
-        // Because Windows was only supported starting with version 0.30.0, we also skip version prior to that when running on windows.
-        if (semver.lt(rel.tag_name, IS_WINDOWS ? '0.30.0' : '0.15.0')) {
-          return false;
-        }
-
-        // Because flow 0.57 was broken before 0.57.3 on the Windows platform, we also skip those versions when running on windows.
-        if (
-          IS_WINDOWS &&
-          (semver.eq(rel.tag_name, '0.57.0') ||
-            semver.eq(rel.tag_name, '0.57.1') ||
-            semver.eq(rel.tag_name, '0.57.2'))
-        ) {
-          return false;
-        }
-        return true;
-      })
-      .map(rel => {
-        // Find the binary zip in the list of assets
-        const binZip = rel.assets
-          .filter(({name}) => {
-            return OS_ARCH_FILTER_RE.test(name) && !/-latest.zip$/.test(name);
-          })
-          .map(asset => asset.browser_download_url);
-
-        if (binZip.length !== 1) {
-          throw new Error(
-            'Unexpected number of ' +
-              BIN_PLATFORM +
-              ' assets for flow-' +
-              rel.tag_name +
-              '! ' +
-              JSON.stringify(binZip),
-          );
-        } else {
-          const version =
-            rel.tag_name[0] === 'v' ? rel.tag_name : 'v' + rel.tag_name;
-          return {version, binURL: binZip[0]};
-        }
-      })
-      .sort((a, b) => {
-        return semver.lt(a.version, b.version) ? -1 : 1;
-      });
-
-    await P.all(
-      flowBins.map(async ({version, binURL}) => {
-        const zipPath = path.join(BIN_DIR, 'flow-' + version + '.zip');
-        const binPath = path.join(
-          BIN_DIR,
-          'flow-' + version + (IS_WINDOWS ? '.exe' : ''),
-        );
-
-        if (await fs.exists(binPath)) {
-          return;
-        }
-
-        // Download the zip file
-        await new Promise((res, rej) => {
-          console.log('  Fetching flow-%s...', version);
-          got
-            .stream(binURL, {
-              headers: {
-                'User-Agent':
-                  'flow-typed Test Runner ' +
-                  '(github.com/flowtype/flow-typed)',
-              },
-            })
-            .on('error', err => rej(err))
-            .pipe(
-              fs.createWriteStream(zipPath).on('close', () => {
-                console.log('    flow-%s finished downloading.', version);
-                res();
-              }),
-            );
-        });
-
-        // Extract the flow binary
-        const flowBinDirPath = path.join(BIN_DIR, 'TMP-flow-' + version);
-        await fs.mkdir(flowBinDirPath);
-        console.log('  Extracting flow-%s...', version);
-        await new Promise((res, rej) => {
-          const unzipExtractor = unzip.Extract({path: flowBinDirPath});
-          unzipExtractor.on('error', function(err) {
-            rej(err);
-          });
-          unzipExtractor.on('close', function() {
-            res();
-          });
-          fs.createReadStream(zipPath).pipe(unzipExtractor);
-        });
-        if (IS_WINDOWS) {
-          await fs.rename(
-            path.join(flowBinDirPath, 'flow', 'flow.exe'),
-            path.join(BIN_DIR, 'flow-' + version + '.exe'),
-          );
-        } else {
-          await fs.rename(
-            path.join(flowBinDirPath, 'flow', 'flow'),
-            path.join(BIN_DIR, 'flow-' + version),
-          );
-
-          await child_process.execP(
-            ['chmod', '755', path.join(BIN_DIR, 'flow-' + version)].join(' '),
-          );
-        }
-
-        console.log('  Removing flow-%s artifacts...', version);
-        await P.all([recursiveRmdir(flowBinDirPath), fs.unlink(zipPath)]);
-        console.log('    flow-%s complete!', version);
-      }),
-    );
-
-    console.log('Finished fetching Flow binaries.\n');
-
-    return flowBins.map(bin => bin.version);
-  })());
-}
-
-const flowNameRegex = /^flow-v[0-9]+.[0-9]+.[0-9]+(\.exe)?$/;
-/**
- * flow filename should be `flow-vx.x.x`
- * @param {string} name
- */
-function checkFlowFilename(name) {
-  return flowNameRegex.test(name);
-}
-
-/**
- * Return the sorted list of cached flow binaries that have previously been retrieved from github
- * and cached in the `.flow-bins-cache` directory.  This function is usually called when a failure
- * has occurred when attempting to refresh the flow releases from github, i.e. offline or over
- * API limit.
- */
-async function getCachedFlowBinVersions(
-  numberOfReleases: number = 15,
-): Promise<Array<string>> {
-  // read the files with name `flow-vx.x.x` from the bin dir and remove the leading `flow-v` prefix
-  const versions: any[] = (await fs.readdir(path.join(BIN_DIR)))
-    .filter(checkFlowFilename)
-    .map(dir => dir.slice(6));
-
-  // sort the versions that we have inplace
-  versions.sort((a, b) => {
-    return semver.lt(a, b) ? -1 : 1;
-  });
-
-  versions.splice(0, versions.length - numberOfReleases);
-
-  // return the versions with a leading 'v' to satisfy the expected return value
-  return versions.map(version => `v${version}`);
-}
-
 async function writeFlowConfig(
   repoDirPath,
   testDirPath,
@@ -309,52 +96,25 @@ async function writeFlowConfig(
   await fs.writeFile(destFlowConfigPath, flowConfigData);
 }
 
-function testTypeDefinition(flowVer, testDirPath) {
-  return new Promise(res => {
-    const child = child_process.exec(
-      [
-        path.join(BIN_DIR, 'flow-' + flowVer),
-        'check',
-        '--strip-root',
-        '--all',
-        testDirPath,
-      ].join(' '),
-    );
-
-    let stdErrOut = '';
-    child.stdout.on('data', data => (stdErrOut += data));
-    child.stderr.on('data', data => (stdErrOut += data));
-
-    child.on('error', execError => {
-      res({stdErrOut, errCode: null, execError});
-    });
-
-    child.on('close', errCode => {
-      res({stdErrOut, errCode, execError: null});
-    });
-  });
-}
-
-async function runFlowTypeDefTests(flowVersionsToRun, groupId, testDirPath) {
-  const errors = [];
-  while (flowVersionsToRun.length > 0) {
+async function runFlowTypeDefTests(flowsToRun, groupId, testDirPath) {
+  const errors: Array<string> = [];
+  while (flowsToRun.length > 0) {
     // Run tests in batches to avoid saturation
-    const testBatch = flowVersionsToRun
-      .slice(0, Math.min(flowVersionsToRun.length, 5))
-      .map(group => (flowVersionsToRun.shift(), group));
+    const testBatch = flowsToRun
+      .slice(0, Math.min(flowsToRun.length, 5))
+      .map(group => (flowsToRun.shift(), group));
 
-    await P.all(
-      testBatch.map(async flowVer => {
-        const testRunId = groupId + ' (flow-' + flowVer + ')';
+    await Promise.all(
+      testBatch.map(async flow => {
+        const testRunId = groupId + ' (flow-' + flow.version + ')';
 
         console.log('Testing %s...', testRunId);
 
-        const {stdErrOut, errCode, execError} = await testTypeDefinition(
-          flowVer,
+        const {stdErrOut, errCode, execError} = await flow.runTests(
           testDirPath,
         );
 
-        if (execError !== null) {
+        if (execError) {
           errors.push(
             testRunId + ': Error executing Flow process: ' + execError.stack,
           );
@@ -378,80 +138,63 @@ async function runFlowTypeDefTests(flowVersionsToRun, groupId, testDirPath) {
 async function testLowestCapableFlowVersion(
   lowerVersions,
   testDirPath,
-  lowestFlowVersionRan,
+  lowestFlowRan,
 ) {
   let lowerFlowVersionsToRun = lowerVersions;
-  let lowestCapableFlowVersion = lowestFlowVersionRan;
+  let lowestCapableFlow = lowestFlowRan;
   while (lowerFlowVersionsToRun.length > 0) {
     const lowerTestBatch = lowerFlowVersionsToRun
       .slice(0, Math.min(lowerFlowVersionsToRun.length, 5))
       .map(group => (lowerFlowVersionsToRun.shift(), group));
 
-    await P.all(
-      lowerTestBatch.map(async flowVer => {
-        const {stdErrOut, execError} = await testTypeDefinition(
-          flowVer,
-          testDirPath,
-        );
+    await Promise.all(
+      lowerTestBatch.map(async flow => {
+        const {stdErrOut, execError} = await flow.runTests(testDirPath);
 
         if (execError !== null || !stdErrOut.endsWith('Found 0 errors\n')) {
           lowerFlowVersionsToRun = [];
         } else {
-          lowestCapableFlowVersion = semver.lt(
-            lowestCapableFlowVersion,
-            flowVer,
-          )
-            ? lowestCapableFlowVersion
-            : flowVer;
+          lowestCapableFlow = semver.lt(lowestCapableFlow.version, flow.version)
+            ? lowestCapableFlow
+            : flow;
         }
       }),
     );
   }
-  return lowestCapableFlowVersion;
+  return lowestCapableFlow;
 }
 
 async function findLowestCapableFlowVersion(
   repoDirPath,
-  orderedFlowVersions,
-  lowestFlowVersionRan,
+  flows,
+  lowestFlowRan,
   testDirPath,
   libDefPath,
 ) {
-  let lowerFlowVersionsToRun = orderedFlowVersions.filter(flowVer => {
-    return semver.lt(flowVer, lowestFlowVersionRan);
+  let lowerFlowsToRun = flows.filter(flow => {
+    return semver.lt(flow.version, lowestFlowRan.version);
   });
-  lowerFlowVersionsToRun.reverse();
-  const lowerLowVersions = lowerFlowVersionsToRun.filter(flowVer =>
-    semver.lt(flowVer, '0.53.0'),
+  lowerFlowsToRun.reverse();
+  const lowerLowFlow = lowerFlowsToRun.filter(flow =>
+    semver.lt(flow.version, '0.53.0'),
   );
-  const higherLowVersions = lowerFlowVersionsToRun.filter(flowVer =>
-    semver.gte(flowVer, '0.53.0'),
+  const higherLowFlows = lowerFlowsToRun.filter(flow =>
+    semver.gte(flow.version, '0.53.0'),
   );
   await writeFlowConfig(repoDirPath, testDirPath, libDefPath, true);
-  const lowestOfHigherVersions = await testLowestCapableFlowVersion(
-    higherLowVersions,
+  const lowestOfHigherFlow = await testLowestCapableFlowVersion(
+    higherLowFlows,
     testDirPath,
-    lowestFlowVersionRan,
+    lowestFlowRan,
   );
   await writeFlowConfig(repoDirPath, testDirPath, libDefPath, false);
   return await testLowestCapableFlowVersion(
-    lowerLowVersions,
+    lowerLowFlow,
     testDirPath,
-    lowestOfHigherVersions,
+    lowestOfHigherFlow,
   );
 }
 
-/**
- * Remove all files except flow instances
- */
-async function removeTrashFromBinDir() {
-  (await fs.readdir(path.join(BIN_DIR)))
-    .filter(name => !checkFlowFilename(name))
-    .forEach(async el => {
-      await fs.unlink(path.resolve(BIN_DIR, el));
-    });
-}
-
 /**
  * Given a TestGroup structure determine all versions of Flow that match the
  * FlowVersion specification and, for each, run `flow check` on the test
@@ -460,7 +203,7 @@ async function removeTrashFromBinDir() {
 async function runTestGroup(
   repoDirPath: string,
   testGroup: TestGroup,
-  orderedFlowVersions: Array<string>,
+  flowBins: Array<Flow>,
 ): Promise<Array<string>> {
   const errors = [];
   // Some older versions of Flow choke on ">"/"<"/"="
@@ -491,8 +234,8 @@ async function runTestGroup(
       path.basename(testGroup.libDefPath),
     );
     const copiedFileNames = new Set();
-    await P.all([
-      P.all(
+    await Promise.all([
+      Promise.all(
         testGroup.testFilePaths.map(async (filePath, idx) => {
           // Because there could be multiple test files with the same basename,
           // we disambiguate each one with a locally-unique index.
@@ -515,21 +258,20 @@ async function runTestGroup(
     // For each compatible version of Flow, run `flow check` and verify there
     // are no errors.
     const testGrpFlowSemVerRange = flowVerToSemverString(testGroup.flowVersion);
-    const flowVersionsToRun = orderedFlowVersions.filter(flowVer => {
-      return semver.satisfies(flowVer, testGrpFlowSemVerRange);
+    const flowsToRun = flowBins.filter(flow => {
+      return semver.satisfies(flow.version, testGrpFlowSemVerRange);
     });
 
-    // Windows hasn't flow < 30.0 but we have tests for flow < 30.0. We need skip it. Example: redux_v3
-    if (!flowVersionsToRun.length) {
+    if (!flowsToRun.length) {
       return [];
     }
-    let lowestFlowVersionRan = flowVersionsToRun[0];
+    let lowestFlowRan = flowsToRun[0];
 
-    const lowerVersions = flowVersionsToRun.filter(flowVer =>
-      semver.lt(flowVer, '0.53.0'),
+    const lowerVersions = flowsToRun.filter(flow =>
+      semver.lt(flow.version, '0.53.0'),
     );
-    const higherVersions = flowVersionsToRun.filter(flowVer =>
-      semver.gte(flowVer, '0.53.0'),
+    const higherVersions = flowsToRun.filter(flow =>
+      semver.gte(flow.version, '0.53.0'),
     );
 
     await writeFlowConfig(
@@ -552,19 +294,19 @@ async function runTestGroup(
     );
 
     errors.push(...higherVersionErrors, ...lowerVersionErrors);
-    const lowestCapableFlowVersion = await findLowestCapableFlowVersion(
+    const lowestCapableFlow = await findLowestCapableFlowVersion(
       repoDirPath,
-      orderedFlowVersions,
-      lowestFlowVersionRan,
+      flowBins,
+      lowestFlowRan,
       testDirPath,
       testGroup.libDefPath,
     );
 
-    if (lowestCapableFlowVersion !== lowestFlowVersionRan) {
-      console.log(`Tests for ${
-        testGroup.id
-      } ran successfully on flow ${lowestCapableFlowVersion}.
-        Consider setting ${lowestCapableFlowVersion} as the lower bound!`);
+    if (lowestCapableFlow.version !== lowestFlowRan.version) {
+      console.log(`Tests for ${testGroup.id} ran successfully on flow ${
+        lowestCapableFlow.version
+      }.
+        Consider setting ${lowestCapableFlow.version} as the lower bound!`);
     }
 
     return errors;
@@ -579,7 +321,7 @@ async function runTests(
   repoDirPath: string,
   testPatterns: Array<string>,
   onlyChanged?: boolean,
-  numberOfFlowVersions?: number,
+  flowBins: Array<Flow>,
 ): Promise<Map<string, Array<string>>> {
   const testPatternRes = testPatterns.map(patt => new RegExp(patt, 'g'));
   const testGroups = (await getTestGroups(repoDirPath, onlyChanged)).filter(
@@ -609,23 +351,11 @@ async function runTests(
     const results = new Map();
     while (testGroups.length > 0) {
       const testGroup = testGroups.shift();
-      //Prepare bin folder to collect flow instances
-      await removeTrashFromBinDir();
-      let orderedFlowVersions;
-      try {
-        orderedFlowVersions = await getOrderedFlowBinVersions(
-          numberOfFlowVersions,
-        );
-      } catch (e) {
-        orderedFlowVersions = await getCachedFlowBinVersions(
-          numberOfFlowVersions,
-        );
-      }
 
       const testGroupErrors = await runTestGroup(
         repoDirPath,
         testGroup,
-        orderedFlowVersions,
+        flowBins,
       );
       if (testGroupErrors.length > 0) {
         const errors = results.get(testGroup.id) || [];
@@ -676,7 +406,8 @@ export async function run(argv: Args): Promise<number> {
   }
   const testPatterns = argv._.slice(1);
   const onlyChanged = Boolean(argv.onlyChanged);
-  const numberOfFlowVersions = Number(argv.numberOfFlowVersions) || 15;
+  const numberOfFlowVersions =
+    Number(argv.numberOfFlowVersions) || NUMBER_OF_FLOW_VERSIONS;
 
   const cwd = process.cwd();
   const basePath = argv.path ? String(argv.path) : cwd;
@@ -699,11 +430,12 @@ export async function run(argv: Args): Promise<number> {
     );
   }
 
+  const flowBins = await getFlowBinaries(BIN_DIR, numberOfFlowVersions);
   const results = await runTests(
     repoDirPath,
     testPatterns,
     onlyChanged,
-    numberOfFlowVersions,
+    flowBins,
   );
   console.log(' ');
   Array.from(results).forEach(([testGroupName, errors]) => {
diff --git a/cli/src/lib/binaries.js b/cli/src/lib/binaries.js
new file mode 100644
index 0000000000..33770b9021
--- /dev/null
+++ b/cli/src/lib/binaries.js
@@ -0,0 +1,214 @@
+// @flow
+import {getGitHubClient} from './github';
+import {child_process} from './node';
+import os from 'os';
+import got from 'got';
+import semver from 'semver';
+import fs from 'fs-extra';
+import yauzl from 'yauzl-promise';
+import path from 'path';
+
+const githubClient = getGitHubClient();
+
+function getOsType() {
+  switch (os.type()) {
+    case 'Linux':
+      return 'linux64';
+    case 'Darwin':
+      return 'osx';
+    case 'Windows_NT':
+      return 'win64';
+
+    default:
+      throw new Error('Unsupported os.type()! ' + os.type());
+  }
+}
+
+const isWindows = os.type() === 'Windows_NT';
+export class Flow {
+  binPath: string;
+  version: string;
+
+  constructor(binPath: string) {
+    this.binPath = binPath;
+    // linux/macos flow bins has no ext
+    this.version = isWindows
+      ? path.parse(binPath).name
+      : path.parse(binPath).base;
+  }
+
+  runTests(
+    testDirPath: string,
+  ): Promise<{
+    stdErrOut: string,
+    errCode: ?number,
+    execError: ?Error,
+  }> {
+    return new Promise(res => {
+      const child = child_process.exec(
+        `${this.binPath} check --strip-root --all ${testDirPath}`,
+      );
+
+      let stdErrOut = '';
+      child.stdout.on('data', data => (stdErrOut += data));
+      child.stderr.on('data', data => (stdErrOut += data));
+
+      child.on('error', execError => {
+        res({stdErrOut, errCode: null, execError});
+      });
+
+      child.on('close', errCode => {
+        res({stdErrOut, errCode, execError: null});
+      });
+    });
+  }
+}
+
+function createBinFilename(binRoot, filename) {
+  return isWindows
+    ? path.resolve(binRoot, `${filename}.exe`)
+    : path.resolve(binRoot, filename);
+}
+
+function saveFileFromStream(stream, filepath) {
+  return new Promise(res => {
+    stream.pipe(
+      fs.createWriteStream(filepath).on('close', () => {
+        res();
+      }),
+    );
+  });
+}
+
+async function extractZip(buffer, filepath, flowname) {
+  console.log(`Start unzipping '${flowname}' file`);
+  const zipFile = await yauzl.fromBuffer(buffer);
+  let entry = null;
+  while ((entry = await zipFile.readEntry())) {
+    if (entry.fileName.startsWith('flow/flow')) {
+      break;
+    }
+  }
+  if (!entry) {
+    throw new Error('flow binary not found in zip file');
+  }
+  const readStream = await zipFile.openReadStream(entry);
+  await saveFileFromStream(readStream, filepath);
+  await zipFile.close();
+  console.log(`'${flowname}' unzipped to cache`);
+}
+
+async function downloadBin(url, filepath, flowname) {
+  console.log(`start '${flowname}' downloading`);
+  const response = await got(url, {encoding: null});
+  console.log(`'${flowname}' downloaded`);
+  await extractZip(response.body, filepath, flowname);
+  if (!isWindows) {
+    await child_process.execP(`chmod 755 ${filepath}`);
+  }
+  return new Flow(filepath);
+}
+
+const osType = getOsType();
+function createFileName(version) {
+  return `flow-${osType}-${version}.zip`;
+}
+
+function getBinUrl(assets, version) {
+  const filename = createFileName(version);
+  for (const asset of assets) {
+    if (asset.name === filename) {
+      return asset.browser_download_url;
+    }
+  }
+}
+
+function filterActualVersions(releases, count, binRoot) {
+  function getKey(version) {
+    const major = semver.major(version);
+    const minor = semver.minor(version);
+    return `${major}.${minor}`;
+  }
+
+  return releases.reduce((res, release) => {
+    if (res.length === count) {
+      return res;
+    }
+    const key = getKey(release.tag_name);
+    return res.length && res[res.length - 1].key === key
+      ? res
+      : res.concat({
+          key: key,
+          version: release.tag_name,
+          filename: createBinFilename(binRoot, release.tag_name),
+          binUrl: getBinUrl(release.assets, release.tag_name),
+        });
+  }, []);
+}
+
+async function getActualVersions(count, binRoot) {
+  console.log('fetch data from github');
+  const dataFromGithub = await githubClient.repos.getReleases({
+    owner: 'facebook',
+    repo: 'flow',
+    page: 0,
+    per_page: 100,
+  });
+  console.log('data fetched');
+  return filterActualVersions(dataFromGithub.data, count, binRoot);
+}
+
+async function getCached(cacheLocation) {
+  console.log(`get data from cache`);
+  const files: Array<string> = await fs.readdir(cacheLocation);
+  return files.map(file => new Flow(path.resolve(cacheLocation, file)));
+}
+
+async function removeFile(binPath, filename) {
+  try {
+    await fs.unlink(binPath);
+    console.log(`${filename} removed from cache`);
+  } catch (_) {
+    console.error(`remove '${filename}' failed`);
+  }
+}
+
+function removeOutdatedVersionsFromCache(flows) {
+  return Promise.all(flows.map(f => removeFile(f.binPath, f.version)));
+}
+
+function downloadActualVersionsToCache(versions) {
+  return Promise.all(
+    versions.map(v => downloadBin(v.binUrl, v.filename, v.version)),
+  );
+}
+
+let memoizedFlowBinaries = null;
+export async function getFlowBinaries(binRoot: string, count: number) {
+  if (memoizedFlowBinaries) {
+    return memoizedFlowBinaries;
+  }
+  await fs.mkdirp(binRoot);
+
+  const [cached, actualVersions] = await Promise.all([
+    getCached(binRoot),
+    getActualVersions(count, binRoot),
+  ]);
+
+  const nonCachedVersions = actualVersions.filter(v =>
+    cached.every(c => c.version !== v.version),
+  );
+  const outdatedVersions = cached.filter(c =>
+    actualVersions.every(v => v.version !== c.version),
+  );
+
+  await Promise.all([
+    removeOutdatedVersionsFromCache(outdatedVersions),
+    downloadActualVersionsToCache(nonCachedVersions),
+  ]);
+
+  memoizedFlowBinaries = nonCachedVersions.length
+    ? await getCached(binRoot)
+    : cached;
+  return memoizedFlowBinaries;
+}
diff --git a/cli/src/lib/github.js b/cli/src/lib/github.js
index a646001374..372420a2e9 100644
--- a/cli/src/lib/github.js
+++ b/cli/src/lib/github.js
@@ -2,12 +2,36 @@
 
 import Octokit from '@octokit/rest';
 
-const CLIENT = new Octokit();
+type GetReleasesArgs = {
+  owner: string,
+  repo: string,
+  page: number,
+  per_page: number,
+};
+
+type Releases = {
+  data: $ReadOnlyArray<{
+    tag_name: string,
+    assets: $ReadOnlyArray<{
+      name: string,
+      browser_download_url: string,
+    }>,
+  }>,
+};
+
+type GitHubClient = {
+  repos: {
+    getReleases(args: GetReleasesArgs): Promise<Releases>,
+  },
+  authenticate(args: Object): void,
+};
+
+const CLIENT: GitHubClient = new Octokit();
 
 if (process.env.GH_TOK) {
   CLIENT.authenticate({type: 'oauth', token: process.env.GH_TOK});
 }
 
-export function gitHubClient(): Object {
+export function getGitHubClient() {
   return CLIENT;
 }
diff --git a/cli/yarn.lock b/cli/yarn.lock
index a0eae2704a..6a6899c4de 100644
--- a/cli/yarn.lock
+++ b/cli/yarn.lock
@@ -1009,31 +1009,16 @@ before-after-hook@^1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/before-after-hook/-/before-after-hook-1.1.0.tgz#83165e15a59460d13702cb8febd6a1807896db5a"
 
-big-integer@^1.6.17:
-  version "1.6.26"
-  resolved "https://registry.yarnpkg.com/big-integer/-/big-integer-1.6.26.tgz#3af1672fa62daf2d5ecafacf6e5aa0d25e02c1c8"
-
 binary-extensions@^1.0.0:
   version "1.8.0"
   resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-1.8.0.tgz#48ec8d16df4377eae5fa5884682480af4d95c774"
 
-binary@~0.3.0:
-  version "0.3.0"
-  resolved "https://registry.yarnpkg.com/binary/-/binary-0.3.0.tgz#9f60553bc5ce8c3386f3b553cff47462adecaa79"
-  dependencies:
-    buffers "~0.1.1"
-    chainsaw "~0.1.0"
-
 block-stream@*:
   version "0.0.9"
   resolved "https://registry.yarnpkg.com/block-stream/-/block-stream-0.0.9.tgz#13ebfe778a03205cfe03751481ebb4b3300c126a"
   dependencies:
     inherits "~2.0.0"
 
-bluebird@~3.4.1:
-  version "3.4.7"
-  resolved "https://registry.yarnpkg.com/bluebird/-/bluebird-3.4.7.tgz#f72d760be09b7f76d08ed8fae98b289a8d05fab3"
-
 boom@2.x.x:
   version "2.10.1"
   resolved "https://registry.yarnpkg.com/boom/-/boom-2.10.1.tgz#39c8918ceff5799f83f9492a848f625add0c766f"
@@ -1094,18 +1079,14 @@ btoa-lite@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/btoa-lite/-/btoa-lite-1.0.0.tgz#337766da15801210fdd956c22e9c6891ab9d0337"
 
-buffer-indexof-polyfill@~1.0.0:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/buffer-indexof-polyfill/-/buffer-indexof-polyfill-1.0.1.tgz#a9fb806ce8145d5428510ce72f278bb363a638bf"
+buffer-crc32@~0.2.3:
+  version "0.2.13"
+  resolved "https://registry.yarnpkg.com/buffer-crc32/-/buffer-crc32-0.2.13.tgz#0d333e3f00eac50aa1454abd30ef8c2a5d9a7242"
 
 buffer-shims@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/buffer-shims/-/buffer-shims-1.0.0.tgz#9978ce317388c649ad8793028c3477ef044a8b51"
 
-buffers@~0.1.1:
-  version "0.1.1"
-  resolved "https://registry.yarnpkg.com/buffers/-/buffers-0.1.1.tgz#b24579c3bed4d6d396aeee6d9a8ae7f5482ab7bb"
-
 builtin-modules@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/builtin-modules/-/builtin-modules-1.1.1.tgz#270f076c5a72c02f5b65a47df94c5fe3a278892f"
@@ -1151,12 +1132,6 @@ center-align@^0.1.1:
     align-text "^0.1.3"
     lazy-cache "^1.0.3"
 
-chainsaw@~0.1.0:
-  version "0.1.0"
-  resolved "https://registry.yarnpkg.com/chainsaw/-/chainsaw-0.1.0.tgz#5eab50b28afe58074d0d58291388828b5e5fbc98"
-  dependencies:
-    traverse ">=0.3.0 <0.4"
-
 chalk@^1.1.0, chalk@^1.1.1, chalk@^1.1.3:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/chalk/-/chalk-1.1.3.tgz#a8115c55e4a702fe4d150abd3872822a7e09fc98"
@@ -1481,12 +1456,6 @@ domexception@^1.0.0:
   dependencies:
     webidl-conversions "^4.0.2"
 
-duplexer2@~0.1.4:
-  version "0.1.4"
-  resolved "https://registry.yarnpkg.com/duplexer2/-/duplexer2-0.1.4.tgz#8b12dab878c0d69e3e7891051662a32fc6bddcc1"
-  dependencies:
-    readable-stream "^2.0.2"
-
 duplexer3@^0.1.4:
   version "0.1.4"
   resolved "https://registry.yarnpkg.com/duplexer3/-/duplexer3-0.1.4.tgz#ee01dd1cac0ed3cbc7fdbea37dc0a8f1ce002ce2"
@@ -1652,6 +1621,10 @@ esutils@^2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/esutils/-/esutils-2.0.2.tgz#0abf4f1caa5bcb1f7a9d8acc6dea4faaa04bac9b"
 
+events-intercept@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/events-intercept/-/events-intercept-2.0.0.tgz#adbf38681c5a4b2011c41ee41f61a34cba448897"
+
 exec-sh@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/exec-sh/-/exec-sh-0.2.0.tgz#14f75de3f20d286ef933099b2ce50a90359cef10"
@@ -1745,6 +1718,12 @@ fb-watchman@^2.0.0:
   dependencies:
     bser "^2.0.0"
 
+fd-slicer@~1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/fd-slicer/-/fd-slicer-1.0.1.tgz#8b5bcbd9ec327c5041bf9ab023fd6750f1177e65"
+  dependencies:
+    pend "~1.2.0"
+
 figures@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/figures/-/figures-2.0.0.tgz#3ab1a2d2a62c8bfb431a0c94cb797a2fce27c962"
@@ -2937,10 +2916,6 @@ levn@^0.3.0, levn@~0.3.0:
     prelude-ls "~1.1.2"
     type-check "~0.3.2"
 
-listenercount@~1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/listenercount/-/listenercount-1.0.1.tgz#84c8a72ab59c4725321480c975e6508342e70937"
-
 load-json-file@^1.0.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/load-json-file/-/load-json-file-1.1.0.tgz#956905708d58b4bab4c2261b04f59f31c99374c0"
@@ -3406,6 +3381,10 @@ path-type@^1.0.0:
     pify "^2.0.0"
     pinkie-promise "^2.0.0"
 
+pend@~1.2.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/pend/-/pend-1.2.0.tgz#7a57eb550a6783f9115331fcf4663d5c8e007a50"
+
 performance-now@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/performance-now/-/performance-now-0.2.0.tgz#33ef30c5c77d4ea21c5a53869d91b56d8f2555e5"
@@ -3569,7 +3548,7 @@ readable-stream@^2.0.1, readable-stream@^2.1.4, readable-stream@^2.2.2:
     string_decoder "~1.0.3"
     util-deprecate "~1.0.1"
 
-readable-stream@~2.1.4, readable-stream@~2.1.5:
+readable-stream@~2.1.4:
   version "2.1.5"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.1.5.tgz#66fa8b720e1438b364681f2ad1a63c618448c9d0"
   dependencies:
@@ -3878,10 +3857,6 @@ set-immediate-shim@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/set-immediate-shim/-/set-immediate-shim-1.0.1.tgz#4b2b1b27eb808a9f8dcc481a58e5e56f599f3f61"
 
-setimmediate@~1.0.4:
-  version "1.0.5"
-  resolved "https://registry.yarnpkg.com/setimmediate/-/setimmediate-1.0.5.tgz#290cbb232e306942d7d7ea9b83732ab7856f8285"
-
 shebang-command@^1.2.0:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/shebang-command/-/shebang-command-1.2.0.tgz#44aac65b695b03398968c39f363fee5deafdf1ea"
@@ -4233,10 +4208,6 @@ tr46@^1.0.0:
   dependencies:
     punycode "^2.1.0"
 
-"traverse@>=0.3.0 <0.4":
-  version "0.3.9"
-  resolved "https://registry.yarnpkg.com/traverse/-/traverse-0.3.9.tgz#717b8f220cc0bb7b44e40514c22b2e8bbc70d8b9"
-
 trim-right@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/trim-right/-/trim-right-1.0.1.tgz#cb2e1203067e0c8de1f614094b9fe45704ea6003"
@@ -4294,20 +4265,6 @@ universalify@^0.1.0:
   version "0.1.0"
   resolved "https://registry.yarnpkg.com/universalify/-/universalify-0.1.0.tgz#9eb1c4651debcc670cc94f1a75762332bb967778"
 
-unzipper@^0.8.11:
-  version "0.8.11"
-  resolved "https://registry.yarnpkg.com/unzipper/-/unzipper-0.8.11.tgz#894383dc6b4bdab944e446f665a82d40d167fbd4"
-  dependencies:
-    big-integer "^1.6.17"
-    binary "~0.3.0"
-    bluebird "~3.4.1"
-    buffer-indexof-polyfill "~1.0.0"
-    duplexer2 "~0.1.4"
-    fstream "~1.0.10"
-    listenercount "~1.0.1"
-    readable-stream "~2.1.5"
-    setimmediate "~1.0.4"
-
 url-parse-lax@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/url-parse-lax/-/url-parse-lax-1.0.0.tgz#7af8f303645e9bd79a272e7a14ac68bc0609da73"
@@ -4559,3 +4516,23 @@ yargs@~3.10.0:
     cliui "^2.1.0"
     decamelize "^1.0.0"
     window-size "0.1.0"
+
+yauzl-clone@^1.0.2:
+  version "1.0.3"
+  resolved "https://registry.yarnpkg.com/yauzl-clone/-/yauzl-clone-1.0.3.tgz#155ff4a64a2f3b888c22346c1e54a05fb922d98a"
+  dependencies:
+    events-intercept "^2.0.0"
+
+yauzl-promise@^2.1.2:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/yauzl-promise/-/yauzl-promise-2.1.2.tgz#fb65e1e87720ebc04d4dddc83887c580bd2c2192"
+  dependencies:
+    yauzl "^2.9.1"
+    yauzl-clone "^1.0.2"
+
+yauzl@^2.9.1:
+  version "2.9.1"
+  resolved "https://registry.yarnpkg.com/yauzl/-/yauzl-2.9.1.tgz#a81981ea70a57946133883f029c5821a89359a7f"
+  dependencies:
+    buffer-crc32 "~0.2.3"
+    fd-slicer "~1.0.1"