diff --git a/flake.lock b/flake.lock
index cbf5f41..92ae66b 100644
--- a/flake.lock
+++ b/flake.lock
@@ -20,16 +20,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1754292888,
-        "narHash": "sha256-1ziydHSiDuSnaiPzCQh1mRFBsM2d2yRX9I+5OPGEmIE=",
+        "lastModified": 1764522689,
+        "narHash": "sha256-SqUuBFjhl/kpDiVaKLQBoD8TLD+/cTUzzgVFoaHrkqY=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "ce01daebf8489ba97bd1609d185ea276efdeb121",
+        "rev": "8bb5646e0bed5dbd3ab08c7a7cc15b75ab4e1d0f",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-25.05",
+        "ref": "nixos-25.11",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index 80bb6e3..66c6501 100644
--- a/flake.nix
+++ b/flake.nix
@@ -2,12 +2,18 @@
   description = "Development Environment";
 
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
     flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs, flake-utils }:
-    flake-utils.lib.eachDefaultSystem (system:
+  outputs =
+    { self
+    , nixpkgs
+    , flake-utils
+    ,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
       let
         pkgs = nixpkgs.legacyPackages.${system};
       in
@@ -15,6 +21,7 @@
         devShells.default = pkgs.mkShell {
           packages = with pkgs; [
             go
+            gopls
             golangci-lint
             nodejs
             tailwindcss
diff --git a/pkg/formatters/duration_test.go b/pkg/formatters/duration_test.go
new file mode 100644
index 0000000..07b9d4d
--- /dev/null
+++ b/pkg/formatters/duration_test.go
@@ -0,0 +1,22 @@
+package formatters
+
+import (
+    "testing"
+    "time"
+)
+
+func TestFormatDuration(t *testing.T) {
+    tests := []struct {
+        dur  time.Duration
+        want string
+    }{
+        {0, "N/A"},
+        {22*24*time.Hour + 7*time.Hour + 39*time.Minute + 31*time.Second, "22d 7h 39m 31s"},
+        {5*time.Minute + 15*time.Second, "5m 15s"},
+    }
+    for _, tc := range tests {
+        if got := FormatDuration(tc.dur); got != tc.want {
+            t.Errorf("FormatDuration(%v) = %s, want %s", tc.dur, got, tc.want)
+        }
+    }
+}
diff --git a/pkg/formatters/numbers_test.go b/pkg/formatters/numbers_test.go
new file mode 100644
index 0000000..84498f2
--- /dev/null
+++ b/pkg/formatters/numbers_test.go
@@ -0,0 +1,22 @@
+package formatters
+
+import (
+    "testing"
+)
+
+func TestFormatNumber(t *testing.T) {
+    tests := []struct {
+        input int64
+        want  string
+    }{
+        {0, "0"},
+        {19823, "19.8k"},
+        {1500000, "1.50M"},
+        {-12345, "-12.3k"},
+    }
+    for _, tc := range tests {
+        if got := FormatNumber(tc.input); got != tc.want {
+            t.Errorf("FormatNumber(%d) = %s, want %s", tc.input, got, tc.want)
+        }
+    }
+}
\ No newline at end of file
diff --git a/pkg/ptr/ptr_test.go b/pkg/ptr/ptr_test.go
new file mode 100644
index 0000000..317d960
--- /dev/null
+++ b/pkg/ptr/ptr_test.go
@@ -0,0 +1,73 @@
+package ptr
+
+import (
+	"testing"
+)
+
+func TestOf(t *testing.T) {
+	// Test with different types
+	intVal := 42
+	intPtr := Of(intVal)
+	if *intPtr != intVal {
+		t.Errorf("Expected %d, got %d", intVal, *intPtr)
+	}
+
+	stringVal := "hello"
+	stringPtr := Of(stringVal)
+	if *stringPtr != stringVal {
+		t.Errorf("Expected %s, got %s", stringVal, *stringPtr)
+	}
+
+	floatVal := 3.14
+	floatPtr := Of(floatVal)
+	if *floatPtr != floatVal {
+		t.Errorf("Expected %f, got %f", floatVal, *floatPtr)
+	}
+}
+
+func TestDeref(t *testing.T) {
+	// Test with non-nil pointer
+	intVal := 42
+	intPtr := Of(intVal)
+	result := Deref(intPtr)
+	if result != intVal {
+		t.Errorf("Expected %d, got %d", intVal, result)
+	}
+
+	// Test with nil pointer
+	var nilPtr *int
+	result = Deref(nilPtr)
+	if result != 0 {
+		t.Errorf("Expected 0, got %d", result)
+	}
+
+	// Test with string
+	stringVal := "hello"
+	stringPtr := Of(stringVal)
+	resultStr := Deref(stringPtr)
+	if resultStr != stringVal {
+		t.Errorf("Expected %s, got %s", stringVal, resultStr)
+	}
+
+	// Test with nil string pointer
+	var nilStrPtr *string
+	resultStr = Deref(nilStrPtr)
+	if resultStr != "" {
+		t.Errorf("Expected empty string, got %s", resultStr)
+	}
+}
+
+func TestDerefZeroValue(t *testing.T) {
+	// Test that Deref returns zero value for nil pointers
+	var nilInt *int
+	result := Deref(nilInt)
+	if result != 0 {
+		t.Errorf("Expected zero int, got %d", result)
+	}
+
+	var nilString *string
+	resultStr := Deref(nilString)
+	if resultStr != "" {
+		t.Errorf("Expected zero string, got %s", resultStr)
+	}
+}
diff --git a/pkg/sliceutils/sliceutils_test.go b/pkg/sliceutils/sliceutils_test.go
new file mode 100644
index 0000000..2e80992
--- /dev/null
+++ b/pkg/sliceutils/sliceutils_test.go
@@ -0,0 +1,50 @@
+package sliceutils
+
+import (
+	"testing"
+)
+
+func TestFirst(t *testing.T) {
+	// Test with empty slice
+	var empty []int
+	result, ok := First(empty)
+	if ok != false {
+		t.Errorf("Expected ok=false for empty slice, got %v", ok)
+	}
+	if result != 0 {
+		t.Errorf("Expected zero value for empty slice, got %v", result)
+	}
+
+	// Test with non-empty slice
+	testSlice := []int{1, 2, 3}
+	result, ok = First(testSlice)
+	if ok != true {
+		t.Errorf("Expected ok=true for non-empty slice, got %v", ok)
+	}
+	if result != 1 {
+		t.Errorf("Expected first element, got %v", result)
+	}
+}
+
+func TestMap(t *testing.T) {
+	// Test with empty slice
+	var empty []int
+	result := Map(empty, func(x int) int { return x * 2 })
+	if len(result) != 0 {
+		t.Errorf("Expected empty result for empty input, got %v", result)
+	}
+
+	// Test with non-empty slice
+	testSlice := []int{1, 2, 3}
+	result = Map(testSlice, func(x int) int { return x * 2 })
+	expected := []int{2, 4, 6}
+	if len(result) != len(expected) {
+		t.Errorf("Expected length %d, got %d", len(expected), len(result))
+	}
+	for i, v := range result {
+		if v != expected[i] {
+			t.Errorf("Expected %d at index %d, got %d", expected[i], i, v)
+		}
+	}
+}
+
diff --git a/pkg/utils/utils_test.go b/pkg/utils/utils_test.go
new file mode 100644
index 0000000..d4a2dba
--- /dev/null
+++ b/pkg/utils/utils_test.go
@@ -0,0 +1,45 @@
+package utils
+
+import (
+	"testing"
+)
+
+func TestTernary(t *testing.T) {
+	// Test true condition
+	result := Ternary(true, 42, 13)
+	if result != 42 {
+		t.Errorf("Expected 42, got %d", result)
+	}
+
+	// Test false condition
+	result = Ternary(false, 42, 13)
+	if result != 13 {
+		t.Errorf("Expected 13, got %d", result)
+	}
+}
+
+func TestFirstNonZero(t *testing.T) {
+	// Test with int values
+	result := FirstNonZero(0, 0, 42, 13)
+	if result != 42 {
+		t.Errorf("Expected 42, got %d", result)
+	}
+
+	// Test with string values
+	resultStr := FirstNonZero("", "", "hello")
+	if resultStr != "hello" {
+		t.Errorf("Expected hello, got %s", resultStr)
+	}
+
+	// Test all zero values (strings)
+	zeroResultStr := FirstNonZero("")
+	if zeroResultStr != "" {
+		t.Errorf("Expected empty string, got %s", zeroResultStr)
+	}
+
+	// Test with float values
+	floatResult := FirstNonZero(0.0, 0.0, 3.14)
+	if floatResult != 3.14 {
+		t.Errorf("Expected 3.14, got %f", floatResult)
+	}
+}
\ No newline at end of file