diff --git a/hopp.lock b/hopp.lock
index 7f51231..ba7d642 100644
--- a/hopp.lock
+++ b/hopp.lock
@@ -1 +1 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/test/fixtures/concat-simple/dist/bundle.js b/test/fixtures/concat-simple/dist/bundle.js
new file mode 100644
index 0000000..91dc758
--- /dev/null
+++ b/test/fixtures/concat-simple/dist/bundle.js
@@ -0,0 +1,9 @@
+console.log(1)
+console.log(2)
+console.log(3)
+console.log(4)
+console.log(5)
+console.log(6)
+console.log(7)
+console.log(8)
+console.log(9)
diff --git a/test/fixtures/concat-simple/expected.js b/test/fixtures/concat-simple/expected.js
new file mode 100644
index 0000000..91dc758
--- /dev/null
+++ b/test/fixtures/concat-simple/expected.js
@@ -0,0 +1,9 @@
+console.log(1)
+console.log(2)
+console.log(3)
+console.log(4)
+console.log(5)
+console.log(6)
+console.log(7)
+console.log(8)
+console.log(9)
diff --git a/test/fixtures/concat-simple/hoppfile.js b/test/fixtures/concat-simple/hoppfile.js
new file mode 100644
index 0000000..a19ba07
--- /dev/null
+++ b/test/fixtures/concat-simple/hoppfile.js
@@ -0,0 +1,8 @@
+const hopp = require('hopp')
+
+hopp.load(`${__dirname}/../../../packages/hopp-plugin-concat`)
+
+exports.default =
+  hopp('src/*.js')
+    .concat()
+    .dest('dist/bundle.js')
\ No newline at end of file
diff --git a/test/fixtures/concat-simple/src/1.js b/test/fixtures/concat-simple/src/1.js
new file mode 100644
index 0000000..e14c4f2
--- /dev/null
+++ b/test/fixtures/concat-simple/src/1.js
@@ -0,0 +1 @@
+console.log(1)
diff --git a/test/fixtures/concat-simple/src/2.js b/test/fixtures/concat-simple/src/2.js
new file mode 100644
index 0000000..32926e2
--- /dev/null
+++ b/test/fixtures/concat-simple/src/2.js
@@ -0,0 +1 @@
+console.log(2)
diff --git a/test/fixtures/concat-simple/src/3.js b/test/fixtures/concat-simple/src/3.js
new file mode 100644
index 0000000..5c92023
--- /dev/null
+++ b/test/fixtures/concat-simple/src/3.js
@@ -0,0 +1 @@
+console.log(3)
diff --git a/test/fixtures/concat-simple/src/4.js b/test/fixtures/concat-simple/src/4.js
new file mode 100644
index 0000000..e2d2ea9
--- /dev/null
+++ b/test/fixtures/concat-simple/src/4.js
@@ -0,0 +1 @@
+console.log(4)
diff --git a/test/fixtures/concat-simple/src/5.js b/test/fixtures/concat-simple/src/5.js
new file mode 100644
index 0000000..41fb1c3
--- /dev/null
+++ b/test/fixtures/concat-simple/src/5.js
@@ -0,0 +1 @@
+console.log(5)
diff --git a/test/fixtures/concat-simple/src/6.js b/test/fixtures/concat-simple/src/6.js
new file mode 100644
index 0000000..581666f
--- /dev/null
+++ b/test/fixtures/concat-simple/src/6.js
@@ -0,0 +1 @@
+console.log(6)
diff --git a/test/fixtures/concat-simple/src/7.js b/test/fixtures/concat-simple/src/7.js
new file mode 100644
index 0000000..af68cfe
--- /dev/null
+++ b/test/fixtures/concat-simple/src/7.js
@@ -0,0 +1 @@
+console.log(7)
diff --git a/test/fixtures/concat-simple/src/8.js b/test/fixtures/concat-simple/src/8.js
new file mode 100644
index 0000000..3f28a90
--- /dev/null
+++ b/test/fixtures/concat-simple/src/8.js
@@ -0,0 +1 @@
+console.log(8)
diff --git a/test/fixtures/concat-simple/src/9.js b/test/fixtures/concat-simple/src/9.js
new file mode 100644
index 0000000..2674a8f
--- /dev/null
+++ b/test/fixtures/concat-simple/src/9.js
@@ -0,0 +1 @@
+console.log(9)
diff --git a/test/test-fixtures-concat-simple.js b/test/test-fixtures-concat-simple.js
new file mode 100644
index 0000000..926c154
--- /dev/null
+++ b/test/test-fixtures-concat-simple.js
@@ -0,0 +1,32 @@
+/**
+ * @file test/test-copy.js
+ * @license MIT
+ * @copyright
+ */
+
+const fs = require('fs')
+const path = require('path')
+const rf = require('rimraf').sync
+const hopp = require('./utils/hopp')
+const shouldExist = require('./utils/exist')
+
+describe('hopp#concat', () => {
+  it('should concat (without options) properly: src/*.js -> dist/bundle.js', async () => {
+    rf(`${__dirname}/fixtures/concat-simple/dist`)
+    rf(`${__dirname}/fixtures/concat-simple/hopp.lock`)
+
+    // run hopp, no args
+    await expect(hopp([], {
+      cwd: `${__dirname}/fixtures/concat-simple`
+    })).resolves.toBeDefined()
+
+    // check for files
+    shouldExist(`${__dirname}/fixtures/concat-simple/dist/bundle.js`)
+    shouldExist(`${__dirname}/fixtures/concat-simple/hopp.lock`)
+
+    const expected = fs.readFileSync(`${__dirname}/fixtures/concat-simple/expected.js`, 'utf8')
+    const given = fs.readFileSync(`${__dirname}/fixtures/concat-simple/dist/bundle.js`, 'utf8')
+
+    expect(given).toBe(expected)
+  })
+})
\ No newline at end of file