diff --git a/cmd/task/task.go b/cmd/task/task.go
index d99db44d..dde290c2 100644
--- a/cmd/task/task.go
+++ b/cmd/task/task.go
@@ -140,9 +140,7 @@ func main() {
 	}
 
 	calls, globals := args.Parse(pflag.Args()...)
-	for name, value := range globals {
-		e.Taskfile.Vars[name] = value
-	}
+	e.Taskfile.Vars.Merge(globals)
 
 	ctx := context.Background()
 	if !watch {
diff --git a/internal/args/args.go b/internal/args/args.go
index acea9c29..e157db32 100644
--- a/internal/args/args.go
+++ b/internal/args/args.go
@@ -7,9 +7,9 @@ import (
 )
 
 // Parse parses command line argument: tasks and vars of each task
-func Parse(args ...string) ([]taskfile.Call, taskfile.Vars) {
+func Parse(args ...string) ([]taskfile.Call, *taskfile.Vars) {
 	var calls []taskfile.Call
-	var globals taskfile.Vars
+	var globals *taskfile.Vars
 
 	for _, arg := range args {
 		if !strings.Contains(arg, "=") {
@@ -19,18 +19,16 @@ func Parse(args ...string) ([]taskfile.Call, taskfile.Vars) {
 
 		if len(calls) < 1 {
 			if globals == nil {
-				globals = taskfile.Vars{}
+				globals = &taskfile.Vars{}
 			}
-
 			name, value := splitVar(arg)
-			globals[name] = taskfile.Var{Static: value}
+			globals.Set(name, taskfile.Var{Static: value})
 		} else {
 			if calls[len(calls)-1].Vars == nil {
-				calls[len(calls)-1].Vars = make(taskfile.Vars)
+				calls[len(calls)-1].Vars = &taskfile.Vars{}
 			}
-
-			name, value := splitVar((arg))
-			calls[len(calls)-1].Vars[name] = taskfile.Var{Static: value}
+			name, value := splitVar(arg)
+			calls[len(calls)-1].Vars.Set(name, taskfile.Var{Static: value})
 		}
 	}
 
diff --git a/internal/args/args_test.go b/internal/args/args_test.go
index 8dc96e4c..779b37f9 100644
--- a/internal/args/args_test.go
+++ b/internal/args/args_test.go
@@ -14,7 +14,7 @@ func TestArgs(t *testing.T) {
 	tests := []struct {
 		Args            []string
 		ExpectedCalls   []taskfile.Call
-		ExpectedGlobals taskfile.Vars
+		ExpectedGlobals *taskfile.Vars
 	}{
 		{
 			Args: []string{"task-a", "task-b", "task-c"},
@@ -29,16 +29,22 @@ func TestArgs(t *testing.T) {
 			ExpectedCalls: []taskfile.Call{
 				{
 					Task: "task-a",
-					Vars: taskfile.Vars{
-						"FOO": taskfile.Var{Static: "bar"},
+					Vars: &taskfile.Vars{
+						Keys: []string{"FOO"},
+						Mapping: map[string]taskfile.Var{
+							"FOO": taskfile.Var{Static: "bar"},
+						},
 					},
 				},
 				{Task: "task-b"},
 				{
 					Task: "task-c",
-					Vars: taskfile.Vars{
-						"BAR": taskfile.Var{Static: "baz"},
-						"BAZ": taskfile.Var{Static: "foo"},
+					Vars: &taskfile.Vars{
+						Keys: []string{"BAR", "BAZ"},
+						Mapping: map[string]taskfile.Var{
+							"BAR": taskfile.Var{Static: "baz"},
+							"BAZ": taskfile.Var{Static: "foo"},
+						},
 					},
 				},
 			},
@@ -48,8 +54,11 @@ func TestArgs(t *testing.T) {
 			ExpectedCalls: []taskfile.Call{
 				{
 					Task: "task-a",
-					Vars: taskfile.Vars{
-						"CONTENT": taskfile.Var{Static: "with some spaces"},
+					Vars: &taskfile.Vars{
+						Keys: []string{"CONTENT"},
+						Mapping: map[string]taskfile.Var{
+							"CONTENT": taskfile.Var{Static: "with some spaces"},
+						},
 					},
 				},
 			},
@@ -60,8 +69,11 @@ func TestArgs(t *testing.T) {
 				{Task: "task-a"},
 				{Task: "task-b"},
 			},
-			ExpectedGlobals: taskfile.Vars{
-				"FOO": {Static: "bar"},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+				},
 			},
 		},
 		{
@@ -81,9 +93,12 @@ func TestArgs(t *testing.T) {
 			ExpectedCalls: []taskfile.Call{
 				{Task: "default"},
 			},
-			ExpectedGlobals: taskfile.Vars{
-				"FOO": {Static: "bar"},
-				"BAR": {Static: "baz"},
+			ExpectedGlobals: &taskfile.Vars{
+				Keys: []string{"FOO", "BAR"},
+				Mapping: map[string]taskfile.Var{
+					"FOO": {Static: "bar"},
+					"BAR": {Static: "baz"},
+				},
 			},
 		},
 	}
diff --git a/internal/compiler/compiler.go b/internal/compiler/compiler.go
index aa31d893..75dcb3ee 100644
--- a/internal/compiler/compiler.go
+++ b/internal/compiler/compiler.go
@@ -7,6 +7,6 @@ import (
 // Compiler handles compilation of a task before its execution.
 // E.g. variable merger, template processing, etc.
 type Compiler interface {
-	GetVariables(t *taskfile.Task, call taskfile.Call) (taskfile.Vars, error)
+	GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error)
 	HandleDynamicVar(v taskfile.Var) (string, error)
 }
diff --git a/internal/compiler/env.go b/internal/compiler/env.go
index 4a9ecf4c..283577cc 100644
--- a/internal/compiler/env.go
+++ b/internal/compiler/env.go
@@ -9,16 +9,12 @@ import (
 
 // GetEnviron the all return all environment variables encapsulated on a
 // taskfile.Vars
-func GetEnviron() taskfile.Vars {
-	var (
-		env = os.Environ()
-		m   = make(taskfile.Vars, len(env))
-	)
-
-	for _, e := range env {
+func GetEnviron() *taskfile.Vars {
+	m := &taskfile.Vars{}
+	for _, e := range os.Environ() {
 		keyVal := strings.SplitN(e, "=", 2)
 		key, val := keyVal[0], keyVal[1]
-		m[key] = taskfile.Var{Static: val}
+		m.Set(key, taskfile.Var{Static: val})
 	}
 	return m
 }
diff --git a/internal/compiler/v2/compiler_v2.go b/internal/compiler/v2/compiler_v2.go
index f42b5fbe..6bcbfaf2 100644
--- a/internal/compiler/v2/compiler_v2.go
+++ b/internal/compiler/v2/compiler_v2.go
@@ -19,8 +19,8 @@ var _ compiler.Compiler = &CompilerV2{}
 type CompilerV2 struct {
 	Dir string
 
-	Taskvars     taskfile.Vars
-	TaskfileVars taskfile.Vars
+	Taskvars     *taskfile.Vars
+	TaskfileVars *taskfile.Vars
 
 	Expansions int
 
@@ -36,10 +36,10 @@ type CompilerV2 struct {
 // 3. Taskfile variables
 // 4. Taskvars file variables
 // 5. Environment variables
-func (c *CompilerV2) GetVariables(t *taskfile.Task, call taskfile.Call) (taskfile.Vars, error) {
+func (c *CompilerV2) GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
 	vr := varResolver{c: c, vars: compiler.GetEnviron()}
-	vr.vars["TASK"] = taskfile.Var{Static: t.Task}
-	for _, vars := range []taskfile.Vars{c.Taskvars, c.TaskfileVars, call.Vars, t.Vars} {
+	vr.vars.Set("TASK", taskfile.Var{Static: t.Task})
+	for _, vars := range []*taskfile.Vars{c.Taskvars, c.TaskfileVars, call.Vars, t.Vars} {
 		for i := 0; i < c.Expansions; i++ {
 			vr.merge(vars)
 		}
@@ -49,16 +49,16 @@ func (c *CompilerV2) GetVariables(t *taskfile.Task, call taskfile.Call) (taskfil
 
 type varResolver struct {
 	c    *CompilerV2
-	vars taskfile.Vars
+	vars *taskfile.Vars
 	err  error
 }
 
-func (vr *varResolver) merge(vars taskfile.Vars) {
+func (vr *varResolver) merge(vars *taskfile.Vars) {
 	if vr.err != nil {
 		return
 	}
 	tr := templater.Templater{Vars: vr.vars}
-	for k, v := range vars {
+	vars.Range(func(k string, v taskfile.Var) error {
 		v = taskfile.Var{
 			Static: tr.Replace(v.Static),
 			Sh:     tr.Replace(v.Sh),
@@ -66,10 +66,11 @@ func (vr *varResolver) merge(vars taskfile.Vars) {
 		static, err := vr.c.HandleDynamicVar(v)
 		if err != nil {
 			vr.err = err
-			return
+			return err
 		}
-		vr.vars[k] = taskfile.Var{Static: static}
-	}
+		vr.vars.Set(k, taskfile.Var{Static: static})
+		return nil
+	})
 	vr.err = tr.Err()
 }
 
diff --git a/internal/taskfile/call.go b/internal/taskfile/call.go
index eec41031..c1ca1083 100644
--- a/internal/taskfile/call.go
+++ b/internal/taskfile/call.go
@@ -3,5 +3,5 @@ package taskfile
 // Call is the parameters to a task call
 type Call struct {
 	Task string
-	Vars Vars
+	Vars *Vars
 }
diff --git a/internal/taskfile/cmd.go b/internal/taskfile/cmd.go
index ea267811..c992dd30 100644
--- a/internal/taskfile/cmd.go
+++ b/internal/taskfile/cmd.go
@@ -10,14 +10,14 @@ type Cmd struct {
 	Cmd         string
 	Silent      bool
 	Task        string
-	Vars        Vars
+	Vars        *Vars
 	IgnoreError bool
 }
 
 // Dep is a task dependency
 type Dep struct {
 	Task string
-	Vars Vars
+	Vars *Vars
 }
 
 var (
@@ -51,7 +51,7 @@ func (c *Cmd) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	}
 	var taskCall struct {
 		Task string
-		Vars Vars
+		Vars *Vars
 	}
 	if err := unmarshal(&taskCall); err == nil {
 		c.Task = taskCall.Task
@@ -70,7 +70,7 @@ func (d *Dep) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	}
 	var taskCall struct {
 		Task string
-		Vars Vars
+		Vars *Vars
 	}
 	if err := unmarshal(&taskCall); err == nil {
 		d.Task = taskCall.Task
diff --git a/internal/taskfile/merge.go b/internal/taskfile/merge.go
index d350e4b9..24b3ebb0 100644
--- a/internal/taskfile/merge.go
+++ b/internal/taskfile/merge.go
@@ -29,18 +29,13 @@ func Merge(t1, t2 *Taskfile, namespaces ...string) error {
 	}
 
 	if t1.Vars == nil {
-		t1.Vars = make(Vars)
+		t1.Vars = &Vars{}
 	}
-	for k, v := range t2.Vars {
-		t1.Vars[k] = v
-	}
-
 	if t1.Env == nil {
-		t1.Env = make(Vars)
-	}
-	for k, v := range t2.Env {
-		t1.Env[k] = v
+		t1.Env = &Vars{}
 	}
+	t1.Vars.Merge(t2.Vars)
+	t1.Env.Merge(t2.Env)
 
 	if t1.Tasks == nil {
 		t1.Tasks = make(Tasks)
diff --git a/internal/taskfile/read/taskvars.go b/internal/taskfile/read/taskvars.go
index f664cf04..cc5bcaa8 100644
--- a/internal/taskfile/read/taskvars.go
+++ b/internal/taskfile/read/taskvars.go
@@ -12,8 +12,8 @@ import (
 )
 
 // Taskvars reads a Taskvars for a given directory
-func Taskvars(dir string) (taskfile.Vars, error) {
-	vars := make(taskfile.Vars)
+func Taskvars(dir string) (*taskfile.Vars, error) {
+	vars := &taskfile.Vars{}
 
 	path := filepath.Join(dir, "Taskvars.yml")
 	if _, err := os.Stat(path); err == nil {
@@ -29,24 +29,17 @@ func Taskvars(dir string) (taskfile.Vars, error) {
 		if err != nil {
 			return nil, err
 		}
-
-		if vars == nil {
-			vars = osVars
-		} else {
-			for k, v := range osVars {
-				vars[k] = v
-			}
-		}
+		vars.Merge(osVars)
 	}
 
 	return vars, nil
 }
 
-func readTaskvars(file string) (taskfile.Vars, error) {
+func readTaskvars(file string) (*taskfile.Vars, error) {
 	f, err := os.Open(file)
 	if err != nil {
 		return nil, err
 	}
 	var vars taskfile.Vars
-	return vars, yaml.NewDecoder(f).Decode(&vars)
+	return &vars, yaml.NewDecoder(f).Decode(&vars)
 }
diff --git a/internal/taskfile/task.go b/internal/taskfile/task.go
index f00ee947..d39999cf 100644
--- a/internal/taskfile/task.go
+++ b/internal/taskfile/task.go
@@ -19,8 +19,8 @@ type Task struct {
 	Status        []string
 	Preconditions []*Precondition
 	Dir           string
-	Vars          Vars
-	Env           Vars
+	Vars          *Vars
+	Env           *Vars
 	Silent        bool
 	Method        string
 	Prefix        string
@@ -55,8 +55,8 @@ func (t *Task) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		Status        []string
 		Preconditions []*Precondition
 		Dir           string
-		Vars          Vars
-		Env           Vars
+		Vars          *Vars
+		Env           *Vars
 		Silent        bool
 		Method        string
 		Prefix        string
diff --git a/internal/taskfile/taskfile.go b/internal/taskfile/taskfile.go
index bcb7653c..b8cf5da9 100644
--- a/internal/taskfile/taskfile.go
+++ b/internal/taskfile/taskfile.go
@@ -7,8 +7,8 @@ type Taskfile struct {
 	Output     string
 	Method     string
 	Includes   IncludedTaskfiles
-	Vars       Vars
-	Env        Vars
+	Vars       *Vars
+	Env        *Vars
 	Tasks      Tasks
 	Silent     bool
 }
@@ -21,8 +21,8 @@ func (tf *Taskfile) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		Output     string
 		Method     string
 		Includes   IncludedTaskfiles
-		Vars       Vars
-		Env        Vars
+		Vars       *Vars
+		Env        *Vars
 		Tasks      Tasks
 		Silent     bool
 	}
@@ -41,8 +41,5 @@ func (tf *Taskfile) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	if tf.Expansions <= 0 {
 		tf.Expansions = 2
 	}
-	if tf.Vars == nil {
-		tf.Vars = make(Vars)
-	}
 	return nil
 }
diff --git a/internal/taskfile/taskfile_test.go b/internal/taskfile/taskfile_test.go
index 9b229a07..fcdd4bb1 100644
--- a/internal/taskfile/taskfile_test.go
+++ b/internal/taskfile/taskfile_test.go
@@ -33,9 +33,12 @@ vars:
 		{
 			yamlTaskCall,
 			&taskfile.Cmd{},
-			&taskfile.Cmd{Task: "another-task", Vars: taskfile.Vars{
-				"PARAM1": taskfile.Var{Static: "VALUE1"},
-				"PARAM2": taskfile.Var{Static: "VALUE2"},
+			&taskfile.Cmd{Task: "another-task", Vars: &taskfile.Vars{
+				Keys: []string{"PARAM1", "PARAM2"},
+				Mapping: map[string]taskfile.Var{
+					"PARAM1": taskfile.Var{Static: "VALUE1"},
+					"PARAM2": taskfile.Var{Static: "VALUE2"},
+				},
 			}},
 		},
 		{
@@ -46,9 +49,12 @@ vars:
 		{
 			yamlTaskCall,
 			&taskfile.Dep{},
-			&taskfile.Dep{Task: "another-task", Vars: taskfile.Vars{
-				"PARAM1": taskfile.Var{Static: "VALUE1"},
-				"PARAM2": taskfile.Var{Static: "VALUE2"},
+			&taskfile.Dep{Task: "another-task", Vars: &taskfile.Vars{
+				Keys: []string{"PARAM1", "PARAM2"},
+				Mapping: map[string]taskfile.Var{
+					"PARAM1": taskfile.Var{Static: "VALUE1"},
+					"PARAM2": taskfile.Var{Static: "VALUE2"},
+				},
 			}},
 		},
 	}
diff --git a/internal/taskfile/var.go b/internal/taskfile/var.go
index 225aed1e..99946f8a 100644
--- a/internal/taskfile/var.go
+++ b/internal/taskfile/var.go
@@ -3,6 +3,8 @@ package taskfile
 import (
 	"errors"
 	"strings"
+
+	"gopkg.in/yaml.v3"
 )
 
 var (
@@ -11,17 +13,86 @@ var (
 )
 
 // Vars is a string[string] variables map.
-type Vars map[string]Var
+type Vars struct {
+	Keys    []string
+	Mapping map[string]Var
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (vs *Vars) UnmarshalYAML(node *yaml.Node) error {
+	if node.Kind != yaml.MappingNode {
+		return errors.New("task: vars is not a map")
+	}
+
+	// NOTE(@andreynering): on this style of custom unmarsheling,
+	// even number contains the keys, while odd numbers contains
+	// the values.
+	for i := 0; i < len(node.Content); i += 2 {
+		keyNode := node.Content[i]
+		valueNode := node.Content[i+1]
+
+		var v Var
+		if err := valueNode.Decode(&v); err != nil {
+			return err
+		}
+		vs.Set(keyNode.Value, v)
+	}
+	return nil
+}
+
+// Merge merges the given Vars into the caller one
+func (vs *Vars) Merge(other *Vars) {
+	other.Range(func(key string, value Var) error {
+		vs.Set(key, value)
+		return nil
+	})
+}
+
+// Set sets a value to a given key
+func (vs *Vars) Set(key string, value Var) {
+	if vs == nil {
+		vs = &Vars{}
+	}
+	if vs.Mapping == nil {
+		vs.Mapping = make(map[string]Var, 1)
+	}
+	if !strSliceContains(vs.Keys, key) {
+		vs.Keys = append(vs.Keys, key)
+	}
+	vs.Mapping[key] = value
+}
+
+func strSliceContains(s []string, str string) bool {
+	for _, v := range s {
+		if v == str {
+			return true
+		}
+	}
+	return false
+}
+
+// Range allows you to loop into the vars in its right order
+func (vs *Vars) Range(yield func(key string, value Var) error) error {
+	if vs == nil {
+		return nil
+	}
+	for _, k := range vs.Keys {
+		if err := yield(k, vs.Mapping[k]); err != nil {
+			return err
+		}
+	}
+	return nil
+}
 
 // ToCacheMap converts Vars to a map containing only the static
 // variables
-func (vs Vars) ToCacheMap() (m map[string]interface{}) {
-	m = make(map[string]interface{}, len(vs))
-	for k, v := range vs {
+func (vs *Vars) ToCacheMap() (m map[string]interface{}) {
+	m = make(map[string]interface{}, len(vs.Keys))
+	vs.Range(func(k string, v Var) error {
 		if v.Sh != "" {
 			// Dynamic variable is not yet resolved; trigger
 			// <no value> to be used in templates.
-			continue
+			return nil
 		}
 
 		if v.Live != nil {
@@ -29,7 +100,8 @@ func (vs Vars) ToCacheMap() (m map[string]interface{}) {
 		} else {
 			m[k] = v.Static
 		}
-	}
+		return nil
+	})
 	return
 }
 
diff --git a/internal/templater/templater.go b/internal/templater/templater.go
index b395070a..b905b1ba 100644
--- a/internal/templater/templater.go
+++ b/internal/templater/templater.go
@@ -12,7 +12,7 @@ import (
 // happen will be assigned to r.err, and consecutive calls to funcs will just
 // return the zero value.
 type Templater struct {
-	Vars taskfile.Vars
+	Vars *taskfile.Vars
 
 	cacheMap map[string]interface{}
 	err      error
@@ -57,20 +57,22 @@ func (r *Templater) ReplaceSlice(strs []string) []string {
 	return new
 }
 
-func (r *Templater) ReplaceVars(vars taskfile.Vars) taskfile.Vars {
-	if r.err != nil || len(vars) == 0 {
+func (r *Templater) ReplaceVars(vars *taskfile.Vars) *taskfile.Vars {
+	if r.err != nil || vars == nil || len(vars.Keys) == 0 {
 		return nil
 	}
 
-	new := make(taskfile.Vars, len(vars))
-	for k, v := range vars {
-		new[k] = taskfile.Var{
+	var new taskfile.Vars
+	vars.Range(func(k string, v taskfile.Var) error {
+		new.Set(k, taskfile.Var{
 			Static: r.Replace(v.Static),
 			Live:   v.Live,
 			Sh:     r.Replace(v.Sh),
-		}
-	}
-	return new
+		})
+		return nil
+	})
+
+	return &new
 }
 
 func (r *Templater) Err() error {
diff --git a/task.go b/task.go
index be6740ca..0e3eb327 100644
--- a/task.go
+++ b/task.go
@@ -52,7 +52,7 @@ type Executor struct {
 	Output      output.Output
 	OutputStyle string
 
-	taskvars taskfile.Vars
+	taskvars *taskfile.Vars
 
 	taskCallCount map[string]*int32
 	mkdirMutexMap map[string]*sync.Mutex
diff --git a/variables.go b/variables.go
index d3160171..a2ef97d8 100644
--- a/variables.go
+++ b/variables.go
@@ -50,19 +50,19 @@ func (e *Executor) CompiledTask(call taskfile.Call) (*taskfile.Task, error) {
 		new.Prefix = new.Task
 	}
 
-	new.Env = make(taskfile.Vars, len(e.Taskfile.Env)+len(origTask.Env))
-	for k, v := range r.ReplaceVars(e.Taskfile.Env) {
-		new.Env[k] = v
-	}
-	for k, v := range r.ReplaceVars(origTask.Env) {
-		new.Env[k] = v
-	}
-	for k, v := range new.Env {
+	new.Env = &taskfile.Vars{}
+	new.Env.Merge(r.ReplaceVars(e.Taskfile.Env))
+	new.Env.Merge(r.ReplaceVars(origTask.Env))
+	err = new.Env.Range(func(k string, v taskfile.Var) error {
 		static, err := e.Compiler.HandleDynamicVar(v)
 		if err != nil {
-			return nil, err
+			return err
 		}
-		new.Env[k] = taskfile.Var{Static: static}
+		new.Env.Set(k, taskfile.Var{Static: static})
+		return nil
+	})
+	if err != nil {
+		return nil, err
 	}
 
 	if len(origTask.Cmds) > 0 {
@@ -103,7 +103,7 @@ func (e *Executor) CompiledTask(call taskfile.Call) (*taskfile.Task, error) {
 			if err != nil {
 				return nil, err
 			}
-			vars[strings.ToUpper(checker.Kind())] = taskfile.Var{Live: value}
+			vars.Set(strings.ToUpper(checker.Kind()), taskfile.Var{Live: value})
 		}
 
 		// Adding new variables, requires us to refresh the templaters