diff --git a/lua/promise/test/helper.lua b/lua/promise/test/helper.lua
index 7e426a6..d0b5069 100644
--- a/lua/promise/test/helper.lua
+++ b/lua/promise/test/helper.lua
@@ -2,6 +2,8 @@ local helper = require("vusted.helper")
 local plugin_name = helper.get_module_root(...)
 
 helper.root = helper.find_plugin_root(plugin_name)
+vim.opt.packpath:prepend(vim.fs.joinpath(helper.root, "spec/.shared/packages"))
+require("assertlib").register(require("vusted.assert").register)
 
 function helper.before_each() end
 
diff --git a/spec/lua/promise/all_settled_spec.lua b/spec/lua/promise/all_settled_spec.lua
index 5666a9b..092cd47 100644
--- a/spec/lua/promise/all_settled_spec.lua
+++ b/spec/lua/promise/all_settled_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.all_settled()", function()
   before_each(helper.before_each)
@@ -22,7 +23,7 @@ describe("Promise.all_settled()", function()
     end)
     on_finished:wait()
 
-    assert.is_same({
+    assert.same({
       { status = "fulfilled", value = 1 },
       { status = "rejected", reason = 2 },
       { status = "fulfilled", value = 3 },
@@ -37,6 +38,6 @@ describe("Promise.all_settled()", function()
       on_finished()
     end)
     on_finished:wait()
-    assert.is_same({}, got)
+    assert.same({}, got)
   end)
 end)
diff --git a/spec/lua/promise/all_spec.lua b/spec/lua/promise/all_spec.lua
index 91ba69a..17d3087 100644
--- a/spec/lua/promise/all_spec.lua
+++ b/spec/lua/promise/all_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.all()", function()
   before_each(helper.before_each)
@@ -22,7 +23,7 @@ describe("Promise.all()", function()
     end)
     on_finished:wait()
 
-    assert.is_same({ 1, 2, 3 }, got)
+    assert.same({ 1, 2, 3 }, got)
   end)
 
   it("resolves even if empty", function()
@@ -33,7 +34,7 @@ describe("Promise.all()", function()
       on_finished()
     end)
     on_finished:wait()
-    assert.is_same({}, got)
+    assert.same({}, got)
   end)
 
   it("rejects if any promise is rejected", function()
diff --git a/spec/lua/promise/any_spec.lua b/spec/lua/promise/any_spec.lua
index ce86278..6ad2468 100644
--- a/spec/lua/promise/any_spec.lua
+++ b/spec/lua/promise/any_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.any()", function()
   before_each(helper.before_each)
@@ -22,7 +23,7 @@ describe("Promise.any()", function()
     end)
     on_finished:wait()
 
-    assert.is_same(1, got)
+    assert.same(1, got)
   end)
 
   it("rejects if empty", function()
@@ -33,7 +34,7 @@ describe("Promise.any()", function()
       on_finished()
     end)
     on_finished:wait()
-    assert.is_same({}, got)
+    assert.same({}, got)
   end)
 
   it("rejects if all promise is rejected", function()
@@ -53,6 +54,6 @@ describe("Promise.any()", function()
     end)
     on_finished:wait()
 
-    assert.is_same({ 1, 2, 3 }, got)
+    assert.same({ 1, 2, 3 }, got)
   end)
 end)
diff --git a/spec/lua/promise/catch_spec.lua b/spec/lua/promise/catch_spec.lua
index 7014e0d..141f789 100644
--- a/spec/lua/promise/catch_spec.lua
+++ b/spec/lua/promise/catch_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("promise:catch()", function()
   before_each(helper.before_each)
@@ -146,6 +147,6 @@ describe("promise:catch()", function()
       end)
     on_finished:wait()
 
-    assert.is_same({ 1, 2, 3 }, got)
+    assert.same({ 1, 2, 3 }, got)
   end)
 end)
diff --git a/spec/lua/promise/finally_spec.lua b/spec/lua/promise/finally_spec.lua
index 54c6a83..9c95bfb 100644
--- a/spec/lua/promise/finally_spec.lua
+++ b/spec/lua/promise/finally_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("promise:finally()", function()
   before_each(helper.before_each)
@@ -42,7 +43,7 @@ describe("promise:finally()", function()
       end)
     on_finished:wait()
 
-    assert.is_same(want, got)
+    assert.same(want, got)
   end)
 
   it("continues from catch()", function()
@@ -84,6 +85,6 @@ describe("promise:finally()", function()
       end)
     on_finished:wait()
 
-    assert.is_same(want, got)
+    assert.same(want, got)
   end)
 end)
diff --git a/spec/lua/promise/new_spec.lua b/spec/lua/promise/new_spec.lua
index c20dbb7..b3fbecb 100644
--- a/spec/lua/promise/new_spec.lua
+++ b/spec/lua/promise/new_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.new()", function()
   before_each(helper.before_each)
diff --git a/spec/lua/promise/next_spec.lua b/spec/lua/promise/next_spec.lua
index 31b578f..9534571 100644
--- a/spec/lua/promise/next_spec.lua
+++ b/spec/lua/promise/next_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("promise:next()", function()
   before_each(helper.before_each)
@@ -51,7 +52,7 @@ describe("promise:next()", function()
     on_finished1:wait()
     on_finished2:wait()
 
-    assert.is_same({ 1, 2, 3, 4 }, got)
+    assert.same({ 1, 2, 3, 4 }, got)
   end)
 
   it("skips catch()", function()
@@ -167,6 +168,6 @@ describe("promise:next()", function()
       end)
     on_finished:wait()
 
-    assert.is_same({ 1, 2, 3 }, got)
+    assert.same({ 1, 2, 3 }, got)
   end)
 end)
diff --git a/spec/lua/promise/race_spec.lua b/spec/lua/promise/race_spec.lua
index b709a15..f9c7fa7 100644
--- a/spec/lua/promise/race_spec.lua
+++ b/spec/lua/promise/race_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.race()", function()
   before_each(helper.before_each)
@@ -30,7 +31,7 @@ describe("Promise.race()", function()
     end)
     on_finished:wait()
 
-    assert.is_same(2, got)
+    assert.same(2, got)
   end)
 
   it("rejects if any promise is rejected", function()
diff --git a/spec/lua/promise/reject_spec.lua b/spec/lua/promise/reject_spec.lua
index e17f09c..62c9f01 100644
--- a/spec/lua/promise/reject_spec.lua
+++ b/spec/lua/promise/reject_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.reject()", function()
   before_each(helper.before_each)
@@ -24,7 +25,7 @@ describe("Promise.reject()", function()
     end)
 
     helper.wait(p)
-    assert.is_same({ want1, want2 }, got)
+    assert.same({ want1, want2 }, got)
   end)
 
   it("if the argument is a promise, returns the promise", function()
diff --git a/spec/lua/promise/resolve_spec.lua b/spec/lua/promise/resolve_spec.lua
index 518ef6d..de9e04e 100644
--- a/spec/lua/promise/resolve_spec.lua
+++ b/spec/lua/promise/resolve_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.resolve()", function()
   before_each(helper.before_each)
@@ -24,7 +25,7 @@ describe("Promise.resolve()", function()
     end)
 
     helper.wait(p)
-    assert.is_same({ want1, want2 }, got)
+    assert.same({ want1, want2 }, got)
   end)
 
   it("if the argument is a promise, returns the promise", function()
diff --git a/spec/lua/promise/with_resolvers_spec.lua b/spec/lua/promise/with_resolvers_spec.lua
index 4a1d548..43bd872 100644
--- a/spec/lua/promise/with_resolvers_spec.lua
+++ b/spec/lua/promise/with_resolvers_spec.lua
@@ -1,5 +1,6 @@
 local helper = require("promise.test.helper")
 local Promise = helper.require("promise")
+local assert = require("assertlib").typed(assert)
 
 describe("Promise.with_resolvers()", function()
   before_each(helper.before_each)
@@ -19,7 +20,7 @@ describe("Promise.with_resolvers()", function()
     end)
     on_finished:wait()
 
-    assert.is_same("ok", got)
+    assert.same("ok", got)
   end)
 
   it("returns promise with reject", function()
@@ -36,6 +37,6 @@ describe("Promise.with_resolvers()", function()
     end)
     on_finished:wait()
 
-    assert.is_same("error", got)
+    assert.same("error", got)
   end)
 end)