diff --git a/spec/test-cars.cr b/spec/test-cars.cr
index 1313c28..df8b17d 100644
--- a/spec/test-cars.cr
+++ b/spec/test-cars.cr
@@ -45,49 +45,59 @@ describe "tracking inconsistencies between implementations" do
 		cars_ram0 = SPECDB::RAMOnly(Car).new "-0"
 		cars_ram1 = SPECDB::RAMOnly(Car).new "-1"
 		cars_ram2 = SPECDB::RAMOnly(Car).new "-2"
+		cars_fifo = SPECDB::FIFO(Car).new "-2", 5
 
-		uncached_searchby_name, uncached_searchby_color, uncached_searchby_keywords = uncached_indexes cars_ram0
-		cached_searchby_name,   cached_searchby_color,   cached_searchby_keywords   = cached_indexes   cars_ram1
-		ram_searchby_name,      ram_searchby_color,      ram_searchby_keywords      = ram_indexes      cars_ram2
+		uncached_searchby_name,    uncached_searchby_color,    uncached_searchby_keywords    = uncached_indexes cars_ram0
+		cached_searchby_name,      cached_searchby_color,      cached_searchby_keywords      = cached_indexes   cars_ram1
+		ram_searchby_name,         ram_searchby_color,         ram_searchby_keywords         = ram_indexes      cars_ram2
+		fifo_cached_searchby_name, fifo_cached_searchby_color, fifo_cached_searchby_keywords = cached_indexes   cars_fifo
 
 		add_cars cars_ram0, 1
 		add_cars cars_ram1, 1
 		add_cars cars_ram2, 1
+		add_cars cars_fifo, 1
 
 		# Searches should be consistent between all implementations of basic indexes, partitions and tags.
 
 		# Basic index.
-		uncached_corvet_car = uncached_searchby_name.get? "Corvet-0"
-		cached_corvet_car   = cached_searchby_name.get?   "Corvet-0"
-		ram_corvet_car      = ram_searchby_name.get?      "Corvet-0"
+		uncached_corvet_car    = uncached_searchby_name.get?    "Corvet-0"
+		cached_corvet_car      = cached_searchby_name.get?      "Corvet-0"
+		ram_corvet_car         = ram_searchby_name.get?         "Corvet-0"
+		fifo_cached_corvet_car = fifo_cached_searchby_name.get? "Corvet-0"
 		uncached_corvet_car.should eq cached_corvet_car
 		uncached_corvet_car.should eq ram_corvet_car
+		uncached_corvet_car.should eq fifo_cached_corvet_car
 		uncached_corvet_car.should eq corvet0
 
 		# Partitions.
 		red_cars = [ Car.new("Corvet-0", "red", [ "shiny", "impressive", "fast", "elegant" ]),
 				Car.new("Ford-5-0", "red", [ "unknown" ])
 			]
-		uncached_red_cars = uncached_searchby_color.get? "red"
-		cached_red_cars   = cached_searchby_color.get?   "red"
-		ram_red_cars      = ram_searchby_color.get?      "red"
+		uncached_red_cars    = uncached_searchby_color.get?    "red"
+		cached_red_cars      = cached_searchby_color.get?      "red"
+		ram_red_cars         = ram_searchby_color.get?         "red"
+		fifo_cached_red_cars = fifo_cached_searchby_color.get? "red"
 		uncached_red_cars.sort.should eq cached_red_cars.sort
 		uncached_red_cars.sort.should eq ram_red_cars.sort
+		uncached_red_cars.sort.should eq fifo_cached_red_cars.sort
 		uncached_red_cars.sort.should eq red_cars.sort
 
 		# Tags.
 		fast_cars = [ Car.new("Corvet-0", "red", [ "shiny", "impressive", "fast", "elegant" ]),
 				Car.new("Bullet-GT-0", "blue", [ "shiny", "fast", "expensive" ])
 			]
-		uncached_fast_cars = uncached_searchby_keywords.get? "fast"
-		cached_fast_cars   = cached_searchby_keywords.get?   "fast"
-		ram_fast_cars      = ram_searchby_keywords.get?      "fast"
+		uncached_fast_cars    = uncached_searchby_keywords.get?    "fast"
+		cached_fast_cars      = cached_searchby_keywords.get?      "fast"
+		ram_fast_cars         = ram_searchby_keywords.get?         "fast"
+		fifo_cached_fast_cars = fifo_cached_searchby_keywords.get? "fast"
 		uncached_fast_cars.sort.should eq cached_fast_cars.sort
 		uncached_fast_cars.sort.should eq ram_fast_cars.sort
+		uncached_fast_cars.sort.should eq fifo_cached_fast_cars.sort
 		uncached_fast_cars.sort.should eq fast_cars.sort
 
 		cars_ram0.rm_storage_dir
 		cars_ram1.rm_storage_dir
 		cars_ram2.rm_storage_dir
+		cars_fifo.rm_storage_dir
 	end
 end