diff --git a/src/consts.typ b/src/consts.typ
index e393728..6211f13 100644
--- a/src/consts.typ
+++ b/src/consts.typ
@@ -1,5 +1,16 @@
 #let Y-SPACE = 10
-#let PAR-PAD = (5pt, 3pt)
 #let PAR-SPACE = 10
 #let COMMENT-PAD = 8
-#let LIFELINE-W = 10
\ No newline at end of file
+#let LIFELINE-W = 10
+
+#let SYM-GAP = 5
+#let PAR-PAD = (5pt, 3pt)
+#let ACTOR-WIDTH = 20
+#let BOUNDARY-HEIGHT = 20
+#let CONTROL-HEIGHT = 20
+#let ENTITY-HEIGHT = 20
+#let DATABASE-WIDTH = 24
+#let COLLECTIONS-PAD = (5pt, 3pt)
+#let COLLECTIONS-DX = 3
+#let COLLECTIONS-DY = 3
+#let QUEUE-PAD = (5pt, 3pt)
\ No newline at end of file
diff --git a/src/participant.typ b/src/participant.typ
index f661d4c..9d7ad3d 100644
--- a/src/participant.typ
+++ b/src/participant.typ
@@ -2,14 +2,36 @@
 #import "consts.typ": *
 
 #let PAR-SPECIALS = "?[]"
+#let SHAPES = (
+  "participant",
+  "actor",
+  "boundary",
+  "control",
+  "entity",
+  "database",
+  "collections",
+  "queue",
+  "custom"
+)
 
-#let _par(name, display-name: auto, from-start: true, invisible: false) = {
+#let _par(
+  name,
+  display-name: auto,
+  from-start: true,
+  invisible: false,
+  shape: "participant",
+  color: rgb("#E2E2F0"),
+  custom-image: none
+) = {
   return ((
     type: "par",
     name: name,
     display-name: if display-name == auto {name} else {display-name},
     from-start: from-start,
-    invisible: invisible
+    invisible: invisible,
+    shape: shape,
+    color: color,
+    custom-image: custom-image
   ),)
 }
 
@@ -26,13 +48,306 @@
   return false
 }
 
-#let render(x-pos, p, y: 0) = {
-  draw.content(
-    (x-pos.at(p.i), y),
-    p.display-name,
-    name: p.name,
-    frame: "rect",
-    padding: PAR-PAD,
-    anchor: "south"
+#let get-size(par) = {
+  if par.invisible {
+    return (width: 0pt, height: 0pt)
+  }
+  let m = measure(box(par.display-name))
+  let w = m.width
+  let h = m.height
+  let (shape-w, shape-h) = (
+    participant: (w + PAR-PAD.last() * 2, h + PAR-PAD.first() * 2),
+    actor: (ACTOR-WIDTH * 1pt, ACTOR-WIDTH * 2pt + SYM-GAP * 1pt + h),
+    boundary: (BOUNDARY-HEIGHT * 2pt, BOUNDARY-HEIGHT * 1pt + SYM-GAP * 1pt + h),
+    control: (CONTROL-HEIGHT * 1pt, CONTROL-HEIGHT * 1pt + SYM-GAP * 1pt + h),
+    entity: (ENTITY-HEIGHT * 1pt, ENTITY-HEIGHT * 1pt + 2pt + SYM-GAP * 1pt + h),
+    database: (DATABASE-WIDTH * 1pt, DATABASE-WIDTH * 4pt / 3 + SYM-GAP * 1pt + h),
+    collections: (
+      w + COLLECTIONS-PAD.last() * 2 + calc.abs(COLLECTIONS-DX) * 1pt,
+      h + COLLECTIONS-PAD.first() * 2 + calc.abs(COLLECTIONS-DY) * 1pt,
+    ),
+    queue: (
+      w + QUEUE-PAD.last() * 2 + 3 * (h + QUEUE-PAD.first() * 2) / 4,
+      h + QUEUE-PAD.first() * 2
+    ),
+    custom: (
+      measure(par.custom-image).width,
+      measure(par.custom-image).height + SYM-GAP * 1pt + h
+    )
+  ).at(par.shape)
+
+  return (
+    width: calc.max(w, shape-w),
+    height: calc.max(h, shape-h)
   )
+}
+
+#let _render-participant(x, y, p, m, bottom) = {
+  let w = m.width / 1pt
+  let h = m.height / 1pt
+  let x0 = x - w / 2 - PAR-PAD.last() / 1pt
+  let x1 = x + w / 2 + PAR-PAD.last() / 1pt
+  let y0 = y + h + PAR-PAD.first() / 1pt * 2
+  if bottom {
+    y0 = y
+  }
+  let y1 = y0 - h - PAR-PAD.first() / 1pt * 2
+
+  draw.rect(
+    (x0, y0),
+    (x1, y1),
+    radius: 2pt,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.content(
+    ((x0 + x1) / 2, (y0 + y1) / 2),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-actor(x, y, p, m, bottom) = {
+  let w2 = ACTOR-WIDTH / 2
+  let head-r = ACTOR-WIDTH / 4
+  let height = ACTOR-WIDTH * 2
+  let arms-y = height * 0.375
+
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
+  draw.circle(
+    (x, y0 - head-r),
+    radius: head-r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line((x, y0 - head-r * 2), (x, y0 - height + w2), stroke: black + .5pt)
+  draw.line((x - w2, y0 - arms-y), (x + w2, y0 - arms-y), stroke: black + .5pt)
+  draw.line((x - w2, y0 - height), (x, y0 - height + w2), (x + w2, y0 - height), stroke: black + .5pt)
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-boundary(x, y, p, m, bottom) = {
+  let circle-r = BOUNDARY-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + BOUNDARY-HEIGHT + SYM-GAP}
+  let x0 = x - BOUNDARY-HEIGHT
+  let y1 = y0 - circle-r
+  let y2 = y0 - BOUNDARY-HEIGHT
+
+  draw.circle(
+    (x + circle-r, y1),
+    radius: circle-r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x0, y0), (x0, y2),
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x0, y1), (x, y1),
+    stroke: black + .5pt
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-control(x, y, p, m, bottom) = {
+  let r = CONTROL-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + CONTROL-HEIGHT + SYM-GAP}
+
+  draw.circle(
+    (x, y0 - r),
+    radius: r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.mark((x, y0), (x - r / 2, y0), symbol: "stealth", fill: black)
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-entity(x, y, p, m, bottom) = {
+  let r = ENTITY-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + ENTITY-HEIGHT + SYM-GAP}
+  let y1 = y0 - ENTITY-HEIGHT - 1.5
+
+  draw.circle(
+    (x, y0 - r),
+    radius: r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x - r, y1),
+    (x + r, y1),
+    stroke: black + .5pt
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-database(x, y, p, m, bottom) = {
+  let height = DATABASE-WIDTH * 4 / 3
+  let rx = DATABASE-WIDTH / 2
+  let ry = rx / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
+  let y1 = y0 - height
+
+  draw.merge-path(
+    close: true,
+    fill: p.color,
+    stroke: black + .5pt,
+    {
+      draw.bezier((x - rx, y0 - ry), (x, y0), (x - rx, y0 - ry/2), (x - rx/2, y0))
+      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0), (x + rx, y0 - ry/2))
+      draw.line((), (x + rx, y1 + ry))
+      draw.bezier((), (x, y1), (x + rx, y1 + ry/2), (x + rx/2, y1))
+      draw.bezier((), (x - rx, y1 + ry), (x - rx/2, y1), (x - rx, y1 + ry/2))
+    }
+  )
+  draw.merge-path(
+    stroke: black + .5pt,
+    {
+      draw.bezier((x - rx, y0 - ry), (x, y0 - ry*2), (x - rx, y0 - 3*ry/2), (x - rx/2, y0 - ry*2))
+      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0 - ry*2), (x + rx, y0 - 3*ry/2))
+    }
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-collections(x, y, p, m, bottom) = {
+  let w = m.width / 1pt
+  let h = m.height / 1pt
+  let dx = COLLECTIONS-DX
+  let dy = COLLECTIONS-DY
+  let total-w = w + PAR-PAD.last() * 2 / 1pt + calc.abs(dx)
+  let total-h = h + PAR-PAD.first() * 2 / 1pt + calc.abs(dy)
+
+  let x0 = x - total-w / 2
+  let x1 = x0 + calc.abs(dx)
+  let x3 = x0 + total-w
+  let x2 = x3 - calc.abs(dx)
+  
+  let y0 = if bottom {y} else {y + total-h}
+  let y1 = y0 - calc.abs(dy)
+  let y3 = y0 - total-h
+  let y2 = y3 + calc.abs(dy)
+
+  let r1 = (x1, y0, x3, y2)
+  let r2 = (x0, y1, x2, y3)
+
+  if dx < 0 {
+    r1.at(0) = x0
+    r1.at(2) = x2
+    r2.at(0) = x1
+    r2.at(2) = x3
+  }
+
+  if dy < 0 {
+    r1.at(1) = y1
+    r1.at(3) = y3
+    r2.at(1) = y0
+    r2.at(3) = y2
+  }
+  draw.rect(
+    (r1.at(0), r1.at(1)),
+    (r1.at(2), r1.at(3)),
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.rect(
+    (r2.at(0), r2.at(1)),
+    (r2.at(2), r2.at(3)),
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  
+  draw.content(
+    ((r2.at(0) + r2.at(2)) / 2, (r2.at(1) + r2.at(3)) / 2),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-queue(x, y, p, m, bottom) = {
+  let w = (m.width + QUEUE-PAD.last() * 2) / 1pt
+  let h = (m.height + QUEUE-PAD.first() * 2) / 1pt
+  let total-h = h
+  let ry = total-h / 2
+  let rx = ry / 2
+  let total-w = w + 3 + 3 * rx
+
+  let x0 = x - total-w / 2
+  let y0 = if bottom {y} else {y + total-h}
+  let y1 = y0 - total-h
+  let x-left = x0 + rx
+  let x-right = x-left + w + rx
+  draw.merge-path(
+    close: true,
+    fill: p.color,
+    stroke: black + .5pt,
+    {
+      draw.bezier((x-right, y0), (x-right + rx, y0 - ry), (x-right + rx/2, y0), (x-right + rx, y0 - ry/2))
+      draw.bezier((), (x-right, y1), (x-right + rx, y1 + ry/2), (x-right + rx/2, y1))
+      draw.line((), (x-left, y1))
+      draw.bezier((), (x-left - rx, y0 - ry), (x-left - rx/2, y1), (x-left - rx, y1 + ry/2))
+      draw.bezier((), (x-left, y0), (x-left - rx, y0 - ry/2), (x-left - rx/2, y0))
+    }
+  )
+  draw.merge-path(
+    stroke: black + .5pt,
+    {
+      draw.bezier((x-right, y0), (x-right - rx, y0 - ry), (x-right - rx/2, y0), (x-right - rx, y0 - ry/2))
+      draw.bezier((), (x-right, y1), (x-right - rx, y1 + ry/2), (x-right - rx/2, y1))
+    }
+  )
+  draw.content(
+    ((x-left + x-right - rx) / 2, y0 - ry),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-custom(x, y, p, m, bottom) = {
+  let image-m = measure(p.custom-image)
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + image-m.height / 1pt + SYM-GAP}
+  draw.content((x - image-m.width / 2pt, y0), p.custom-image, anchor: "north-west")
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let render(x-pos, p, y: 0, bottom: false) = {
+  let m = measure(box(p.display-name))
+  let func = (
+    participant: _render-participant,
+    actor: _render-actor,
+    boundary: _render-boundary,
+    control: _render-control,
+    entity: _render-entity,
+    database: _render-database,
+    collections: _render-collections,
+    queue: _render-queue,
+    custom: _render-custom,
+  ).at(p.shape)
+  func(x-pos.at(p.i), y, p, m, bottom)
 }
\ No newline at end of file
diff --git a/src/renderer.typ b/src/renderer.typ
index d8b1504..d92c63e 100644
--- a/src/renderer.typ
+++ b/src/renderer.typ
@@ -53,15 +53,15 @@
   }
 
   // Compute column widths
-  // Compute minimum widths for participant names
+  // Compute minimum widths for participant names and shapes
   let widths = ()
   for i in range(participants.len() - 1) {
     let p1 = participants.at(i)
     let p2 = participants.at(i + 1)
-    let w1 = if p1.invisible {0pt} else {measure(box(p1.display-name)).width}
-    let w2 = if p2.invisible {0pt} else {measure(box(p2.display-name)).width}
-    w1 += PAR-PAD.last() * 2
-    w2 += PAR-PAD.last() * 2
+    let m1 = participant.get-size(p1)
+    let m2 = participant.get-size(p2)
+    let w1 = m1.width
+    let w2 = m2.width
     widths.push(w1 / 2pt + w2 / 2pt + PAR-SPACE)
   }
 
@@ -267,14 +267,7 @@
       }
 
       // Draw participants (end)
-      draw.content(
-        (x, y),
-        p.display-name,
-        name: p.name,
-        frame: "rect",
-        padding: PAR-PAD,
-        anchor: "north"
-      )
+      draw-par(p, y: y, bottom: true)
     }
   })