diff --git a/fs.appendFile.spec.js b/fs.appendFile.spec.js
deleted file mode 100644
index 5babb9e..0000000
--- a/fs.appendFile.spec.js
+++ /dev/null
@@ -1,224 +0,0 @@
-'use strict';
-
-const util = require('../lib/test-utils.js');
-const expect = require('chai').expect;
-
-describe('fs.appendFile', function() {
-  const contents = 'This is a file.';
-
-  beforeEach(function(done) {
-    util.setup(function() {
-      let fs = util.fs();
-      fs.writeFile('/myfile', contents, function(error) {
-        if(error) throw error;
-        done();
-      });
-    });
-  });
-  afterEach(util.cleanup);
-
-  it('should be a function', function() {
-    let fs = util.fs();
-    expect(fs.appendFile).to.be.a('function');
-  });
-
-  it('should append a utf8 file without specifying utf8 in appendFile', function(done) {
-    let fs = util.fs();
-    const more = ' Appended.';
-
-    fs.appendFile('/myfile', more, function(error) {
-      if(error) throw error;
-
-      fs.readFile('/myfile', 'utf8', function(error, data) {
-        expect(error).not.to.exist;
-        expect(data).to.equal(contents + more);
-        done();
-      });
-    });
-  });
-
-  it('should append a utf8 file with "utf8" option to appendFile', function(done) {
-    let fs = util.fs();
-    const more = ' Appended.';
-
-    fs.appendFile('/myfile', more, 'utf8', function(error) {
-      if(error) throw error;
-
-      fs.readFile('/myfile', 'utf8', function(error, data) {
-        expect(error).not.to.exist;
-        expect(data).to.equal(contents + more);
-        done();
-      });
-    });
-  });
-
-  it('should append a utf8 file with {encoding: "utf8"} option to appendFile', function(done) {
-    let fs = util.fs();
-    const more = ' Appended.';
-
-    fs.appendFile('/myfile', more, { encoding: 'utf8' }, function(error) {
-      if(error) throw error;
-
-      fs.readFile('/myfile', { encoding: 'utf8' }, function(error, data) {
-        expect(error).not.to.exist;
-        expect(data).to.equal(contents + more);
-        done();
-      });
-    });
-  });
-
-  it('should append a binary file', function(done) {
-    let fs = util.fs();
-
-    // String and utf8 binary encoded versions of the same thing: 'This is a file.'
-    const binary = Buffer.from([84, 104, 105, 115, 32, 105, 115, 32, 97, 32, 102, 105, 108, 101, 46]);
-    const binary2 = Buffer.from([32, 65, 112, 112, 101, 110, 100, 101, 100, 46]);
-    const binary3 = Buffer.from([84, 104, 105, 115, 32, 105, 115, 32, 97, 32, 102, 105, 108, 101, 46,
-      32, 65, 112, 112, 101, 110, 100, 101, 100, 46]);
-
-    fs.writeFile('/mybinaryfile', binary, function(error) {
-      if(error) throw error;
-
-      fs.appendFile('/mybinaryfile', binary2, function(error) {
-        if(error) throw error;
-
-        fs.readFile('/mybinaryfile', 'ascii', function(error, data) {
-          expect(error).not.to.exist;
-          expect(data).to.deep.equal(binary3);
-          done();
-        });
-      });
-    });
-  });
-
-  it('should follow symbolic links', function(done) {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-    const more = ' Appended.';
-
-    fs.symlink('/myfile', '/myFileLink', function (error) {
-      if (error) throw error;
-
-      fs.appendFile('/myFileLink', more, 'utf8', function (error) {
-        if (error) throw error;
-
-        fs.readFile('/myFileLink', 'utf8', function(error, data) {
-          expect(error).not.to.exist;
-          expect(data).to.equal(contents + more);
-          done();
-        });
-      });
-    });
-  });
-
-  it('should work when file does not exist, and create the file', function(done) {
-    let fs = util.fs();
-
-    fs.appendFile('/newfile', contents, { encoding: 'utf8' }, function(error) {
-      expect(error).not.to.exist;
-
-      fs.readFile('/newfile', 'utf8', function(err, data) {
-        if(err) throw err;
-        expect(data).to.equal(contents);
-        done();
-      });
-    });
-  });
-  
-  it('should accept numbers and append them to the file', function(done) {
-    let fs = util.fs();
-    const more = 10000;
-
-    fs.appendFile('/myfile', more, 'utf8', function(error) {
-      if(error) throw error;
-
-      fs.readFile('/myfile', 'utf8', function(error, data) {
-        expect(error).not.to.exist;
-        expect(data).to.equal(contents + more);
-        done();
-      });
-    });
-  });
-});
-
-describe('fs.promises.appendFile', function() {
-  beforeEach(function(done) {
-    util.setup(function() {
-      let fs = util.fs();
-      return fs.promises.writeFile('/myfile', 'This is a file.', { encoding: 'utf8' })
-        .then(done)
-        .catch(done);
-    });
-  });
-  afterEach(util.cleanup);
-
-  it('should be a function', function() {
-    let fs = util.fs();
-    expect(fs.promises.appendFile).to.be.a('function');
-  });
-
-  it('should append a utf8 file without specifying utf8 in appendFile', function() {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-    const more = ' Appended.';
-
-    return fs.promises.appendFile('/myfile', more)
-      .then(() => fs.promises.readFile('/myfile', 'utf8'))
-      .then(data => expect(data).to.equal(contents + more));
-  });
-
-  it('should append a utf8 file with "utf8" option to appendFile', function() {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-    const more = ' Appended.';
-
-    return fs.promises.appendFile('/myfile', more, 'utf8')
-      .then(() => fs.promises.readFile('/myfile', 'utf8'))
-      .then(data => expect(data).to.equal(contents + more));
-  });
-
-  it('should append a utf8 file with {encoding: "utf8"} option to appendFile', function() {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-    const more = ' Appended.';
-
-    return fs.promises.appendFile('/myfile', more, { encoding: 'utf8' })
-      .then(() => fs.promises.readFile('/myfile', { encoding: 'utf8' }))
-      .then(data => expect(data).to.equal(contents + more));
-  });
-
-  it('should append a binary file', function() {
-    let fs = util.fs();
-
-    // String and utf8 binary encoded versions of the same thing: 'This is a file.'
-    const binary = new Buffer([84, 104, 105, 115, 32, 105, 115, 32, 97, 32, 102, 105, 108, 101, 46]);
-    const binary2 = new Buffer([32, 65, 112, 112, 101, 110, 100, 101, 100, 46]);
-    const binary3 = new Buffer([84, 104, 105, 115, 32, 105, 115, 32, 97, 32, 102, 105, 108, 101, 46,
-      32, 65, 112, 112, 101, 110, 100, 101, 100, 46]);
-
-    return fs.promises.writeFile('/mybinaryfile', binary)
-      .then(() => fs.promises.appendFile('/mybinaryfile', binary2))
-      .then(() => fs.promises.readFile('/mybinaryfile', 'ascii'))
-      .then(data => expect(data).to.deep.equal(binary3));
-  });
-
-  it('should follow symbolic links', function() {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-    const more = ' Appended.';
-
-    return fs.promises.symlink('/myfile', '/myFileLink')
-      .then(() => fs.promises.appendFile('/myFileLink', more, 'utf8'))
-      .then(() => fs.promises.readFile('/myFileLink', 'utf8'))
-      .then(data => expect(data).to.equal(contents + more));
-  });
-
-  it('should work when file does not exist, and create the file', function() {
-    let fs = util.fs();
-    const contents = 'This is a file.';
-
-    return fs.promises.appendFile('/newfile', contents, { encoding: 'utf8' })
-      .then(() => fs.promises.readFile('/newfile', 'utf8'))
-      .then(data => expect(data).to.equal(contents));
-  });
-});