diff --git a/README.md b/README.md
index 2d28dfa..10fbffe 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,3 @@
 # go-openlibrary
 
-A Go wrapper around the OpenLibrary.org API: https://openlibrary.org/dev/docs/api/books 
\ No newline at end of file
+A simple Go wrapper around the OpenLibrary.org API: <https://openlibrary.org/dev/docs/api/books>.
diff --git a/client/client.go b/client/client.go
new file mode 100644
index 0000000..120f81e
--- /dev/null
+++ b/client/client.go
@@ -0,0 +1,101 @@
+package client
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+)
+
+var (
+	defaultAPI = "https://openlibrary.org/api/books"
+)
+
+// Client
+type Client struct {
+	httpClient http.Client
+	apipath    string
+}
+
+// NewClient returns a new Client struct using http.DefaultClient and default api path.
+func NewClient() (*Client, error) {
+	return &Client{
+		apipath: defaultAPI,
+	}, nil
+}
+
+// SetHTTPClient updates the httpClient on the client with a manually-configured one.
+// If unset, the client will fall back to using http.DefaultClient.
+func (c *Client) SetHTTPClient(h http.Client) {
+	c.httpClient = h
+}
+
+// SetAPIPath updates the hostname and path to the API; the default is "https://openlibrary.org/api/books".
+// If APIPath is set to an empty string, the client will fall back to the default option.
+func (c *Client) SetAPIPath(p string) {
+	c.apipath = p
+}
+
+// GetByISBN fetches details for a book based on its ISBN10 or ISBN13.
+func (c *Client) GetByISBN(k string) (*BookDetails, error) {
+	key := "ISBN:" + k
+	return c.fetch(key)
+}
+
+// GetByOCLC fetches details for a book based on its WorldCat OCLC number.
+func (c *Client) GetByOCLC(k string) (*BookDetails, error) {
+	key := "OCLC:" + k
+	return c.fetch(key)
+}
+
+// GetByLCCN fetches details for a book based on its Library of Congress Control Number.
+func (c *Client) GetByLCCN(k string) (*BookDetails, error) {
+	key := "LCCN:" + k
+	return c.fetch(key)
+}
+
+// GetByOLID fetches details for a book based on its OpenLibrary ID number.
+func (c *Client) GetByOLID(k string) (*BookDetails, error) {
+	key := "OLID:" + k
+	return c.fetch(key)
+}
+
+// GetByRawKey fetches details for a book based on an arbitrary key; this method is provided
+// as a future-proof fallback in case the OpenLibrary API adds more "bibkey" request types in the future.
+// Most users should use one of the other lookup functions.
+func (c *Client) GetByRawKey(k string) (*BookDetails, error) {
+	return c.fetch(k)
+}
+
+func (c *Client) fetch(key string) (*BookDetails, error) {
+	path := c.apipath
+	if path == "" {
+		path = defaultAPI
+	}
+
+	resp, err := c.httpClient.Get(path + "?bibkeys=%s&jscmd=data&format=json")
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("received non-200 status code: %d", resp.StatusCode)
+	}
+
+	var result response
+	b, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+	if err = json.Unmarshal(b, &result); err != nil {
+		return nil, err
+	}
+
+	details, ok := result[key]
+	if !ok {
+		return nil, fmt.Errorf("book not found")
+	}
+
+	return &details, nil
+}
diff --git a/client/response.go b/client/response.go
new file mode 100644
index 0000000..f944da6
--- /dev/null
+++ b/client/response.go
@@ -0,0 +1,71 @@
+package client
+
+type response map[string]BookDetails
+
+type BookDetails struct {
+	Authors         []Authors       `json:"authors"`
+	Classifications Classifications `json:"classifications"`
+	Cover           Cover           `json:"cover"`
+	Excerpts        []Excerpts      `json:"excerpts"`
+	Identifiers     Identifiers     `json:"identifiers"`
+	Links           []Links         `json:"links"`
+	NumberOfPages   int             `json:"number_of_pages"`
+	PublishDate     string          `json:"publish_date"`
+	Publishers      []Publishers    `json:"publishers"`
+	PublishPlaces   []PublishPlaces `json:"publish_places"`
+	Subjects        []Subjects      `json:"subjects"`
+	Title           string          `json:"title"`
+	URL             string          `json:"url"`
+	Weight          string          `json:"weight"`
+}
+
+type Authors struct {
+	Name string `json:"name"`
+	URL  string `json:"url"`
+}
+
+type Classifications struct {
+	DeweyDecimalClass []string `json:"dewey_decimal_class"`
+	LcClassifications []string `json:"lc_classifications"`
+}
+
+type Cover struct {
+	Small  string `json:"small"`
+	Medium string `json:"medium"`
+	Large  string `json:"large"`
+}
+
+type Excerpts struct {
+	Text    string `json:"text"`
+	Comment string `json:"comment"`
+}
+
+type Identifiers struct {
+	Amazon           []string `json:"amazon"`
+	Goodreads        []string `json:"goodreads"`
+	Google           []string `json:"google"`
+	Isbn10           []string `json:"isbn_10"`
+	Isbn13           []string `json:"isbn_13"`
+	Lccn             []string `json:"lccn"`
+	Librarything     []string `json:"librarything"`
+	Oclc             []string `json:"oclc"`
+	ProjectGutenberg []string `json:"project_gutenberg"`
+}
+
+type Links struct {
+	Title string `json:"title"`
+	URL   string `json:"url"`
+}
+
+type Publishers struct {
+	Name string `json:"name"`
+}
+
+type PublishPlaces struct {
+	Name string `json:"name"`
+}
+
+type Subjects struct {
+	Name string `json:"name"`
+	URL  string `json:"url"`
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..a9fd6e2
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module git.yetaga.in/alazyreader/go-openlibrary
+
+go 1.16