diff --git a/app/classifier/__init__.py b/app/classifier/__init__.py
deleted file mode 100644
index e69de29b..00000000
diff --git a/app/classifier/model.py b/app/classifier/model.py
deleted file mode 100644
index 62b0d59d..00000000
--- a/app/classifier/model.py
+++ /dev/null
@@ -1,12 +0,0 @@
-"""
-Baseline model.
-"""
-
-from sklearn.calibration import CalibratedClassifierCV
-from sklearn.svm import LinearSVC
-
-
-def build_model():
-    estimator = CalibratedClassifierCV(base_estimator=LinearSVC())
-
-    return estimator
diff --git a/app/classifier/preprocess.py b/app/classifier/preprocess.py
deleted file mode 100644
index 548f6e8f..00000000
--- a/app/classifier/preprocess.py
+++ /dev/null
@@ -1,27 +0,0 @@
-"""
-Preprocessor.
-"""
-import MeCab
-from sklearn.feature_extraction.text import TfidfVectorizer
-
-t = MeCab.Tagger('-Owakati')
-
-
-def tokenize(text):
-    """Tokenize Japanese text.
-
-    Args:
-        text: Japanese string.
-
-    Returns:
-        A list of words.
-    """
-    words = t.parse(text).rstrip().split()
-
-    return words
-
-
-def build_vectorizer():
-    vectorizer = TfidfVectorizer(tokenizer=tokenize)
-
-    return vectorizer
diff --git a/app/classifier/task.py b/app/classifier/task.py
deleted file mode 100644
index 32e6b88e..00000000
--- a/app/classifier/task.py
+++ /dev/null
@@ -1,34 +0,0 @@
-"""
-Task runner.
-"""
-import numpy as np
-
-from doccano.app.classifier.model import build_model
-from doccano.app.classifier import build_vectorizer
-from doccano.app.classifier import load_dataset, save_dataset, make_output, train_test_split
-
-
-def run(filename):
-    print('Loading dataset...')
-    data = load_dataset(filename)
-    x_train, x_test, y_train, ids = train_test_split(data)
-
-    print('Building vectorizer and model...')
-    vectorizer = build_vectorizer()
-    clf = build_model()
-
-    print('Vectorizing...')
-    x_train = vectorizer.fit_transform(x_train)
-    x_test = vectorizer.transform(x_test)
-
-    print('Fitting...')
-    clf.fit(x_train, y_train)
-
-    print('Predicting...')
-    y_pred = clf.predict(x_test)
-    y_prob = clf.predict_proba(x_test)
-    y_prob = np.max(y_prob, axis=-1)
-
-    print('Saving...')
-    data = make_output(data, ids, y_pred, y_prob)
-    save_dataset(data, filename)
diff --git a/app/classifier/utils.py b/app/classifier/utils.py
deleted file mode 100644
index 068c3183..00000000
--- a/app/classifier/utils.py
+++ /dev/null
@@ -1,45 +0,0 @@
-"""
-Utilities.
-"""
-import json
-
-
-def train_test_split(data):
-    x_train, x_test, y_train, ids = [], [], [], []
-    for d in data:
-        text = d['text']
-        label = d['label']
-        if d['manual']:
-            x_train.append(text)
-            y_train.append(label)
-        else:
-            x_test.append(text)
-            ids.append(d['id'])
-
-    return x_train, x_test, y_train, ids
-
-
-def load_dataset(filename):
-    with open(filename) as f:
-        data = [json.loads(line) for line in f]
-
-    return data
-
-
-def save_dataset(obj, filename):
-    with open(filename, 'w') as f:
-        for line in obj:
-            f.write('{}\n'.format(json.dumps(line)))
-
-
-def make_output(data, ids, y_pred, y_prob):
-    i = 0
-    for d in data:
-        if i == len(ids):
-            break
-        if d['id'] == ids[i]:
-            d['label'] = str(y_pred[i])
-            d['prob'] = float(y_prob[i])
-            i += 1
-
-    return data