diff --git a/api/src/rest/context.rs b/api/src/rest/context.rs
index aaafb1c..09c8e67 100644
--- a/api/src/rest/context.rs
+++ b/api/src/rest/context.rs
@@ -32,3 +32,56 @@ impl From<Context> for domain::Context {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn should_create_default_context() {
+        let query_params = vec![];
+        let rest_ctx = Context::from(&query_params);
+
+        assert_eq!(rest_ctx.lang, None);
+    }
+
+    #[test]
+    fn should_get_lang_from_query_params() {
+        let query_params = vec![("lang", "rus")];
+        let rest_ctx = Context::from(&query_params);
+
+        assert_eq!(rest_ctx.lang, Some(String::from("rus")));
+    }
+
+    #[test]
+    fn should_create_domain_context_from_rest() {
+        let rest_ctx = Context {
+            lang: Some(String::from("rus")),
+        };
+        let ctx = domain::Context::from(rest_ctx);
+
+        assert_eq!(ctx.lang, domain::Lang::Rus);
+
+        let rest_ctx = Context {
+            lang: Some(String::from("eng")),
+        };
+        let ctx = domain::Context::from(rest_ctx);
+
+        assert_eq!(ctx.lang, domain::Lang::Eng);
+    }
+
+    #[test]
+    fn should_fallback_lang_to_default_if_lang_unsupported_or_missed() {
+        let rest_ctx = Context::default();
+        let ctx = domain::Context::from(rest_ctx);
+
+        assert_eq!(ctx.lang, domain::Lang::Rus);
+
+        let rest_ctx = Context {
+            lang: Some(String::from("unsupported")),
+        };
+        let ctx = domain::Context::from(rest_ctx);
+
+        assert_eq!(ctx.lang, domain::Lang::Rus);
+    }
+}
diff --git a/api/src/rest/types.rs b/api/src/rest/types.rs
index 95f5b04..1978d27 100644
--- a/api/src/rest/types.rs
+++ b/api/src/rest/types.rs
@@ -50,3 +50,46 @@ fn extract_query_params(query: Option<&str>) -> Vec<QueryParam> {
         })
         .unwrap_or_default()
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn should_extract_path_segments() {
+        let path = "/hello/world";
+        let segments = extract_path_segments(path);
+
+        assert_eq!(segments, ["hello", "world"]);
+    }
+
+    #[test]
+    fn should_extract_tralling_slash_as_empty_segment() {
+        let path = "/hello/world/";
+        let segments = extract_path_segments(path);
+
+        assert_eq!(segments, ["hello", "world", ""]);
+    }
+
+    #[test]
+    fn should_extract_query_params() {
+        let query_params = Some("lang=rus&keys=apple&keys=banana");
+        let params = extract_query_params(query_params);
+
+        assert_eq!(
+            params[..],
+            [("lang", "rus"), ("keys", "apple"), ("keys", "banana")]
+        );
+    }
+
+    #[test]
+    fn should_parse_whole_url() {
+        let url = Url::parse("/api/ingredients?lang=rus&keys=apple&keys=banana");
+
+        assert_eq!(url.path_segments(), ["api", "ingredients"]);
+        assert_eq!(
+            url.query_params()[..],
+            [("lang", "rus"), ("keys", "apple"), ("keys", "banana")]
+        )
+    }
+}