diff --git a/Gulpfile.js b/Gulpfile.js
index 9123207fbdc8d..a880d46cfb425 100644
--- a/Gulpfile.js
+++ b/Gulpfile.js
@@ -567,23 +567,6 @@ task("baseline-accept").description = "Makes the most recent test results the ne
 task("baseline-accept-rwc", () => baselineAccept(localRwcBaseline, refRwcBaseline));
 task("baseline-accept-rwc").description = "Makes the most recent rwc test results the new baseline, overwriting the old baseline";
 
-// TODO(jakebailey): figure out what tsc-instrumented and such are for and what do to with them.
-
-const buildLoggedIO = () => buildProject("src/loggedIO/tsconfig-tsc-instrumented.json");
-const cleanLoggedIO = () => del("built/local/loggedIO.js");
-cleanTasks.push(cleanLoggedIO);
-
-const buildInstrumenter = () => buildProject("src/instrumenter");
-const cleanInstrumenter = () => cleanProject("src/instrumenter");
-cleanTasks.push(cleanInstrumenter);
-
-const tscInstrumented = () => exec(process.execPath, ["built/local/instrumenter.js", "record", cmdLineOptions.tests || "iocapture", "built/local/tsc.js"]);
-task("tsc-instrumented", series(lkgPreBuild, parallel(localize, buildTsc, buildServer, buildServices, buildLssl, buildLoggedIO, buildInstrumenter), tscInstrumented));
-task("tsc-instrumented").description = "Builds an instrumented tsc.js";
-task("tsc-instrumented").flags = {
-    "-t --tests=<testname>": "The test to run."
-};
-
 // TODO(rbuckton): Determine if we still need this task. Depending on a relative
 //                 path here seems like a bad idea.
 const updateSublime = () => src(["built/local/tsserver.js", "built/local/tsserver.js.map"])
diff --git a/src/instrumenter/instrumenter.ts b/src/instrumenter/instrumenter.ts
deleted file mode 100644
index 641d1734561e4..0000000000000
--- a/src/instrumenter/instrumenter.ts
+++ /dev/null
@@ -1,43 +0,0 @@
-import * as fs from "fs";
-import * as path from "path";
-
-function instrumentForRecording(fn: string, tscPath: string) {
-    instrument(tscPath, `
-ts.sys = Playback.wrapSystem(ts.sys);
-ts.sys.startRecord("${ fn }");`, `ts.sys.endRecord();`);
-}
-
-function instrumentForReplay(logFilename: string, tscPath: string) {
-    instrument(tscPath, `
-ts.sys = Playback.wrapSystem(ts.sys);
-ts.sys.startReplay("${ logFilename }");`);
-}
-
-function instrument(tscPath: string, prepareCode: string, cleanupCode = "") {
-    const bak = `${tscPath}.bak`;
-    const filename = fs.existsSync(bak) ? bak : tscPath;
-    const tscContent = fs.readFileSync(filename, "utf-8");
-    fs.writeFileSync(bak, tscContent);
-    const loggerContent = fs.readFileSync(path.resolve(path.dirname(tscPath) + "/loggedIO.js"), "utf-8");
-    const invocationLine = "ts.executeCommandLine(ts.sys, ts.noop, ts.sys.args);";
-    const index1 = tscContent.indexOf(invocationLine);
-    if (index1 < 0) {
-        throw new Error(`Could not find ${invocationLine}`);
-    }
-    const index2 = index1 + invocationLine.length;
-    const newContent = tscContent.substr(0, index1) + loggerContent + prepareCode + invocationLine + cleanupCode + tscContent.substr(index2) + "\r\n";
-    fs.writeFileSync(tscPath, newContent);
-}
-
-const isJson = (arg: string) => arg.indexOf(".json") > 0;
-
-const record = process.argv.indexOf("record");
-const tscPath = process.argv[process.argv.length - 1];
-if (record >= 0) {
-    console.log(`Instrumenting ${tscPath} for recording`);
-    instrumentForRecording(process.argv[record + 1], tscPath);
-}
-else if (process.argv.some(isJson)) {
-    const filename = process.argv.filter(isJson)[0];
-    instrumentForReplay(filename, tscPath);
-}
diff --git a/src/instrumenter/tsconfig.json b/src/instrumenter/tsconfig.json
deleted file mode 100644
index b20d49e47ce33..0000000000000
--- a/src/instrumenter/tsconfig.json
+++ /dev/null
@@ -1,15 +0,0 @@
-{
-    "compilerOptions": {
-        "module": "commonjs",
-        "target": "es5",
-        "lib": [
-            "es6",
-            "dom",
-            "scripthost"
-        ],
-        "outDir": "../../built/local/instrumenter"
-    },
-    "files": [
-        "instrumenter.ts"
-    ]
-}
diff --git a/src/loggedIO/tsconfig-tsc-instrumented.json b/src/loggedIO/tsconfig-tsc-instrumented.json
deleted file mode 100644
index 65159c293a3aa..0000000000000
--- a/src/loggedIO/tsconfig-tsc-instrumented.json
+++ /dev/null
@@ -1,26 +0,0 @@
-{
-    // TODO: ???
-    "extends": "../tsconfig-base",
-    "compilerOptions": {
-        "outDir": "../../built/local/loggedIO",
-        "types": [
-            "node", "mocha", "chai"
-        ],
-        "lib": [
-            "es6",
-            "scripthost"
-        ]
-    },
-    "references": [
-        { "path": "../compiler" },
-        { "path": "../services" },
-        { "path": "../jsTyping" },
-        { "path": "../server" },
-        { "path": "../typingsInstallerCore" },
-        { "path": "../harness" },
-    ],
-
-    "files": [
-        "loggedIO.ts"
-    ]
-}