diff --git a/testifycheck/README.md b/testifycheck/README.md
new file mode 100644
index 0000000..ef68d19
--- /dev/null
+++ b/testifycheck/README.md
@@ -0,0 +1,8 @@
+# testifycheck
+
+Напишите линтер, который находит неправильные использование функции `{require,assert}.(Not)?Nil` из пакета `testify`.
+
+Линтер должен смотреть на тип аргумента, который передаётся в функцию `require.NotNil`. Если тот является `error`,
+то линтер должен предлагать заменить вызов на `require.NoError`.
+
+Полный список ситуаций, смотрите в тестовом файле `testdata/srcs/tests/errors_test.go`.
diff --git a/testifycheck/testdata/src/github.com/stretchr/testify/assert/assert.go b/testifycheck/testdata/src/github.com/stretchr/testify/assert/assert.go
new file mode 100644
index 0000000..92c6ca9
--- /dev/null
+++ b/testifycheck/testdata/src/github.com/stretchr/testify/assert/assert.go
@@ -0,0 +1,75 @@
+package assert
+
+type TestingT interface {
+	Errorf(format string, args ...interface{})
+}
+
+func NotNil(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func NotNilf(t TestingT, object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func Nil(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func Nilf(t TestingT, object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func NoError(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func NoErrorf(t TestingT, err error, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func Error(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func Errorf(t TestingT, err error, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+type Assertions struct{}
+
+func New(t TestingT) *Assertions {
+	return nil
+}
+
+func (*Assertions) NotNil(object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) NotNilf(object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) Nil(object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) Nilf(object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) NoError(object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) NoErrorf(object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) Error(object interface{}, msgAndArgs ...interface{}) bool {
+	panic("not implemented")
+}
+
+func (*Assertions) Errorf(object interface{}, msg string, args ...interface{}) bool {
+	panic("not implemented")
+}
diff --git a/testifycheck/testdata/src/github.com/stretchr/testify/require/require.go b/testifycheck/testdata/src/github.com/stretchr/testify/require/require.go
new file mode 100644
index 0000000..37e58cb
--- /dev/null
+++ b/testifycheck/testdata/src/github.com/stretchr/testify/require/require.go
@@ -0,0 +1,75 @@
+package require
+
+type TestingT interface {
+	Errorf(format string, args ...interface{})
+}
+
+func NotNil(t TestingT, object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func NotNilf(t TestingT, object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func Nil(t TestingT, object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func Nilf(t TestingT, object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func NoError(t TestingT, object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func NoErrorf(t TestingT, err error, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func Error(t TestingT, object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func Errorf(t TestingT, err error, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+type Assertions struct{}
+
+func New(t TestingT) *Assertions {
+	return nil
+}
+
+func (*Assertions) NotNil(object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) NotNilf(object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) Nil(object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) Nilf(object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) NoError(object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) NoErrorf(object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) Error(object interface{}, msgAndArgs ...interface{}) {
+	panic("not implemented")
+}
+
+func (*Assertions) Errorf(object interface{}, msg string, args ...interface{}) {
+	panic("not implemented")
+}
diff --git a/testifycheck/testdata/src/tests/errors_test.go b/testifycheck/testdata/src/tests/errors_test.go
new file mode 100644
index 0000000..d2628ca
--- /dev/null
+++ b/testifycheck/testdata/src/tests/errors_test.go
@@ -0,0 +1,67 @@
+package tests
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func errorFunc() error {
+	panic("implement me")
+}
+
+func TestFunctions(t *testing.T) {
+	err := errorFunc()
+
+	require.Nil(t, err)    // want `use require.NoError instead of comparing error to nil`
+	require.NotNil(t, err) // want `use require.Error instead of comparing error to nil`
+	assert.Nil(t, err)     // want `use assert.NoError instead of comparing error to nil`
+	assert.NotNil(t, err)  // want `use assert.Error instead of comparing error to nil`
+
+	require.Nilf(t, err, "%s", "a") // want `use require.NoErrorf instead of comparing error to nil`
+	require.NotNilf(t, err, "%s", "a") // want `use require.Errorf instead of comparing error to nil`
+	assert.Nilf(t, err, "%s", "a")     // want `use assert.NoErrorf instead of comparing error to nil`
+	assert.NotNilf(t, err, "%s", "a")  // want `use assert.Errorf instead of comparing error to nil`
+
+	p := new(int)
+
+	require.Nil(t, p)
+	require.NotNil(t, p)
+	assert.Nil(t, p)
+	assert.NotNil(t, p)
+
+	require.Nilf(t, p, "%s", "a")
+	require.NotNilf(t, p, "%s", "a")
+	assert.Nilf(t, p, "%s", "a")
+	assert.NotNilf(t, p, "%s", "a")
+}
+
+func TestAssertions(t *testing.T) {
+	err := errorFunc()
+
+	assert := assert.New(t)
+	require := require.New(t)
+
+	require.Nil(err)    // want `use require.NoError instead of comparing error to nil`
+	require.NotNil(err) // want `use require.Error instead of comparing error to nil`
+	assert.Nil(err)     // want `use assert.NoError instead of comparing error to nil`
+	assert.NotNil(err)  // want `use assert.Error instead of comparing error to nil`
+
+	require.Nilf(err, "%s", "a") // want `use require.NoErrorf instead of comparing error to nil`
+	require.NotNilf(err, "%s", "a") // want `use require.Errorf instead of comparing error to nil`
+	assert.Nilf(err, "%s", "a")     // want `use assert.NoErrorf instead of comparing error to nil`
+	assert.NotNilf(err, "%s", "a")  // want `use assert.Errorf instead of comparing error to nil`
+
+	p := new(int)
+
+	require.Nil(p)
+	require.NotNil(p)
+	assert.Nil(p)
+	assert.NotNil(p)
+
+	require.Nilf(p, "%s", "a")
+	require.NotNilf(p, "%s", "a")
+	assert.Nilf(p, "%s", "a")
+	assert.NotNilf(p, "%s", "a")
+}
diff --git a/testifycheck/testifycheck.go b/testifycheck/testifycheck.go
new file mode 100644
index 0000000..829c1ec
--- /dev/null
+++ b/testifycheck/testifycheck.go
@@ -0,0 +1,3 @@
+// +build !solution
+
+package testifycheck
diff --git a/testifycheck/testifycheck_test.go b/testifycheck/testifycheck_test.go
new file mode 100644
index 0000000..6abb9ac
--- /dev/null
+++ b/testifycheck/testifycheck_test.go
@@ -0,0 +1,12 @@
+package testifycheck
+
+import (
+	"testing"
+
+	"golang.org/x/tools/go/analysis/analysistest"
+)
+
+func Test(t *testing.T) {
+	testdata := analysistest.TestData()
+	analysistest.Run(t, testdata, Analyzer, "tests/...")
+}