diff --git a/internal/genai/gemini.go b/internal/genai/gemini.go
new file mode 100644
index 0000000..2a0bdf7
--- /dev/null
+++ b/internal/genai/gemini.go
@@ -0,0 +1,68 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package genai
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+
+	gemini "github.com/google/generative-ai-go/genai"
+	"google.golang.org/api/option"
+)
+
+type GeminiClient struct {
+	model
+	closer
+}
+
+type model interface {
+	GenerateContent(ctx context.Context, parts ...gemini.Part) (*gemini.GenerateContentResponse, error)
+}
+
+type closer interface {
+	Close() error
+}
+
+const (
+	geminiAPIKeyEnv = "GEMINI_API_KEY"
+	geminiModel     = "gemini-pro"
+)
+
+func NewGeminiClient(ctx context.Context) (*GeminiClient, error) {
+	key := os.Getenv(geminiAPIKeyEnv)
+	if key == "" {
+		return nil, fmt.Errorf("%s must be set", geminiAPIKeyEnv)
+	}
+	client, err := gemini.NewClient(ctx, option.WithAPIKey(key))
+	if err != nil {
+		return nil, err
+	}
+	return &GeminiClient{
+		model:  client.GenerativeModel(geminiModel),
+		closer: client,
+	}, nil
+}
+
+func (c *GeminiClient) GenerateText(ctx context.Context, prompt string) ([]string, error) {
+	response, err := c.model.GenerateContent(ctx, gemini.Text(prompt))
+	if err != nil {
+		return nil, err
+	}
+	b, err := json.Marshal(response)
+	if err == nil {
+		fmt.Println(string(b))
+	}
+	var candidates []string
+	for _, c := range response.Candidates {
+		if c.Content != nil {
+			for _, p := range c.Content.Parts {
+				candidates = append(candidates, fmt.Sprintf("%s", p))
+			}
+		}
+	}
+	return candidates, nil
+}
diff --git a/internal/genai/gemini_test.go b/internal/genai/gemini_test.go
new file mode 100644
index 0000000..5f3f40d
--- /dev/null
+++ b/internal/genai/gemini_test.go
@@ -0,0 +1,52 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package genai
+
+import (
+	"context"
+	"testing"
+
+	gemini "github.com/google/generative-ai-go/genai"
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestGemini(t *testing.T) {
+	c := testGeminiClient()
+
+	got, err := c.GenerateText(context.Background(), "say hello")
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := []string{"Hello there! How can I assist you today?"}
+	if diff := cmp.Diff(want, got); diff != "" {
+		t.Errorf("GenerateText mismatch (-want, +got):\n%s", diff)
+	}
+}
+
+func testGeminiClient() *GeminiClient {
+	return &GeminiClient{
+		model:  testModel{},
+		closer: testCloser{},
+	}
+}
+
+type testModel struct{}
+
+func (_ testModel) GenerateContent(ctx context.Context, parts ...gemini.Part) (*gemini.GenerateContentResponse, error) {
+	// TODO(tatianabradley): Improve testing by replaying a real API response.
+	return &gemini.GenerateContentResponse{
+		Candidates: []*gemini.Candidate{{
+			Content: &gemini.Content{
+				Parts: []gemini.Part{
+					gemini.Text("Hello there! How can I assist you today?"),
+				},
+			},
+		}},
+	}, nil
+}
+
+type testCloser struct{}
+
+func (_ testCloser) Close() error { return nil }