I dont know if pointers help here but now there are pointers

confetti/confetti.go

@@ -34,8 +34,8 @@ type model struct {
 	system *simulation.System
 }
 
-func Spawn(width, height int) []simulation.Particle {
-	particles := []simulation.Particle{}
+func Spawn(width, height int) []*simulation.Particle {
+	particles := []*simulation.Particle{}
 	for i := 0; i < numParticles; i++ {
 		x := float64(width / 2)
 		y := float64(0)
@@ -52,7 +52,7 @@ func Spawn(width, height int) []simulation.Particle {
 				Render(array.Sample(characters)),
 		}
 
-		particles = append(particles, p)
+		particles = append(particles, &p)
 	}
 	return particles
 }

fireworks/fireworks.go

@@ -36,7 +36,7 @@ type model struct {
 	system *simulation.System
 }
 
-func SpawnShoot(width, height int) simulation.Particle {
+func SpawnShoot(width, height int) *simulation.Particle {
 	color := lipgloss.Color(array.Sample(colors))
 	v := float64(rand.Intn(15) + 15.0)
 
@@ -54,14 +54,14 @@ func SpawnShoot(width, height int) simulation.Particle {
 		Shooting:      true,
 		ExplosionCall: SpawnExplosion,
 	}
-	return p
+	return &p
 }
 
-func SpawnExplosion(x, y float64, width, height int) []simulation.Particle {
+func SpawnExplosion(x, y float64, width, height int) []*simulation.Particle {
 	color := lipgloss.Color(array.Sample(colors))
 	v := float64(rand.Intn(10) + 20.0)
 
-	particles := []simulation.Particle{}
+	particles := []*simulation.Particle{}
 
 	for i := 0; i < numParticles; i++ {
 		p := simulation.Particle{
@@ -74,14 +74,14 @@ func SpawnExplosion(x, y float64, width, height int) []simulation.Particle {
 			Char:     lipgloss.NewStyle().Foreground(color).Render(array.Sample(characters)),
 			Shooting: false,
 		}
-		particles = append(particles, p)
+		particles = append(particles, &p)
 	}
 	return particles
 }
 
 func InitialModelWithSize(width, height int) model {
 	return model{system: &simulation.System{
-		Particles: []simulation.Particle{SpawnShoot(width, height)},
+		Particles: []*simulation.Particle{SpawnShoot(width, height)},
 		Frame: simulation.Frame{
 			Width:  width,
 			Height: height,

simulation/simulation.go

@@ -8,7 +8,7 @@ import (
 
 type System struct {
 	Frame     Frame
-	Particles []Particle
+	Particles []*Particle
 }
 
 type Particle struct {
@@ -17,7 +17,7 @@ type Particle struct {
 	Physics       *Projectile
 	Hidden        bool
 	Shooting      bool
-	ExplosionCall func(x, y float64, width, height int) []Particle
+	ExplosionCall func(x, y float64, width, height int) []*Particle
 }
 
 type Frame struct {
@@ -29,7 +29,8 @@ func FPS(n int) float64 {
 	return (time.Second / time.Duration(n)).Seconds()
 }
 
-func RemoveParticleFromArray(s []Particle, i int) []Particle {
+func RemoveParticleFromArray(s []*Particle, i int) []*Particle {
+	s[i] = nil
 	s[i] = s[len(s)-1]
 	return s[:len(s)-1]
 }
@@ -56,7 +57,7 @@ func (s *System) Update() {
 	}
 }
 
-func (s *System) Visible(p Particle) bool {
+func (s *System) Visible(p *Particle) bool {
 	y := int(p.Physics.Position.Y)
 	x := int(p.Physics.Position.X)
 	return !p.Hidden && y >= 0 && y < s.Frame.Height-1 && x >= 0 && x < s.Frame.Width-1