diff --git a/index.html b/index.html
index ba33878..0bb2012 100644
--- a/index.html
+++ b/index.html
@@ -33,20 +33,12 @@
       .root {
         height: 100%;
         display: grid;
-        grid-template-areas:
-          "code eval"
-          "bottom bottom"
-          "statusbar statusbar";
-        grid-template-columns: 60% 40%;
-        grid-template-rows: 1fr 0.7fr 2.5em;
-      }
-
-      .root.embed_value_explorer {
         grid-template-areas:
           "code code"
           "bottom files"
           "statusbar statusbar";
         grid-template-columns: 70% 30%;
+        grid-template-rows: 1fr 0.7fr 2.5em;
       }
 
       .root.fullscreen_editor {
@@ -54,17 +46,16 @@
         grid-template-rows: 1fr 0fr 2.5em;
       }
 
-      .editor_container, .bottom, .eval, .files_container, .statusbar {
+      .editor_container, .bottom, .files_container, .statusbar {
         box-shadow: 1px 1px 3px 0px var(--shadow_color);
       }
 
-      .editor_container, .eval, .bottom, .statusbar, .files_container {
+      .editor_container, .bottom, .statusbar, .files_container {
         margin: 8px;
       }
 
       .editor_container:focus-within, 
       .bottom:focus-within,
-      .eval:focus-within,
       .files_container:focus-within,
       .help_dialog {
         outline: none;
@@ -81,18 +72,6 @@
         font-size: 16px;
       }
 
-      .eval {
-        display: grid;
-        grid-area: eval;
-        overflow: auto;
-        white-space: pre;
-      }
-
-      .eval_content {
-        padding: 5px;
-        outline: none;
-      }
-
       /* ace markers */
 
       .selection {
diff --git a/src/editor/calltree.js b/src/editor/calltree.js
index 5746967..0e0505d 100644
--- a/src/editor/calltree.js
+++ b/src/editor/calltree.js
@@ -1,6 +1,5 @@
 import {exec} from '../index.js'
 import {el, stringify, fn_link, scrollIntoViewIfNeeded} from './domutils.js'
-import {FLAGS} from '../feature_flags.js'
 import {stringify_for_header} from './value_explorer.js'
 import {find_node} from '../ast_utils.js'
 import {is_expandable, root_calltree_node, get_deferred_calls, has_error} 
@@ -37,23 +36,11 @@ export class CallTree {
       }
 
       if(e.key == 'a') {
-        if(FLAGS.embed_value_explorer) {
-          exec('calltree.select_arguments')
-        } else {
-          // TODO make clear that arguments are shown
-          this.ui.eval.show_value(this.state.current_calltree_node.args)
-          this.ui.eval.focus_value_or_error(this.container)
-        }
+        exec('calltree.select_arguments')
       }
 
       if(e.key == 'r' || e.key == 'Enter') {
-        if(FLAGS.embed_value_explorer) {
-          exec('calltree.select_return_value')
-        } else {
-          // TODO make clear that return value is shown
-          this.ui.eval.show_value_or_error(this.state.current_calltree_node)
-          this.ui.eval.focus_value_or_error(this.container)
-        }
+        exec('calltree.select_return_value')
       }
 
       if(e.key == 'ArrowDown' || e.key == 'j'){
diff --git a/src/editor/editor.js b/src/editor/editor.js
index 42060d3..8b35def 100644
--- a/src/editor/editor.js
+++ b/src/editor/editor.js
@@ -1,7 +1,6 @@
 import {exec, get_state} from '../index.js'
 import {ValueExplorer, stringify_for_header} from './value_explorer.js'
 import {el, stringify, fn_link} from './domutils.js'
-import {FLAGS} from '../feature_flags.js'
 
 /*
   normalize events 'change' and 'changeSelection':
@@ -173,6 +172,8 @@ export class Editor {
 
   update_value_explorer_margin() {
     if(this.widget != null) {
+      // TODO: set margin left based on current line width, not on max line
+      // width?
       this.widget.content.style.marginLeft = 
         (this.ace_editor.getSession().getScreenWidth() + 1) + 'ch'
     }
@@ -265,15 +266,9 @@ export class Editor {
   }
 
   focus_value_explorer(return_to) {
-    if(FLAGS.embed_value_explorer) {
-      if(this.widget != null) {
-        this.widget.return_to = return_to
-        this.widget.content.focus({preventScroll: true})
-      }
-    } else {
-      if(get_state().selection_state != null) {
-        this.ui.eval.focus_value_or_error()
-      }
+    if(this.widget != null) {
+      this.widget.return_to = return_to
+      this.widget.content.focus({preventScroll: true})
     }
   }
 
diff --git a/src/editor/eval.js b/src/editor/eval.js
deleted file mode 100644
index ed99c59..0000000
--- a/src/editor/eval.js
+++ /dev/null
@@ -1,67 +0,0 @@
-import {ValueExplorer} from './value_explorer.js'
-import {el} from './domutils.js'
-
-export class Eval {
-
-  constructor(ui, container) {
-    this.ui = ui
-    this.container = container
-
-    this.container.addEventListener('keydown', (e) => {
-      if(e.key == 'Escape') {
-        this.escape()
-      }
-    })
-
-    // TODO jump to fn location, view function calls
-    // container.addEventListener('click', jump_to_fn_location)
-
-  }
-
-  escape() {
-    if(this.focusedFrom == null) {
-      this.ui.editor.focus()
-    } else {
-      this.focusedFrom.focus()
-      this.focusedFrom = null
-    }
-  }
-
-  show_value(value){
-    this.container.innerHTML = ''
-    const container = el('div', {'class': 'eval_content', tabindex: 0})
-    this.container.appendChild(container)
-    const explorer = new ValueExplorer({
-      container,
-      on_escape: () => this.escape()
-    })
-    explorer.render(value)
-  }
-
-  show_error(error){
-    this.container.innerHTML = ''
-    this.container.appendChild(el('span', 'eval_error', error.toString()))
-  }
-
-  show_value_or_error({ok, value, error}){
-    if(ok) {
-      this.show_value(value)
-    } else {
-      this.show_error(error)
-    }
-  }
-
-  clear_value_or_error() {
-    this.container.innerHTML = ''
-  }
-
-  focus_value_or_error(from) {
-    this.focusedFrom = from
-    if(this.container.childElementCount != 1) {
-      throw new Error('illegal state')
-    }
-    this.container.children[0].focus()
-  }
-
-
-}
diff --git a/src/editor/ui.js b/src/editor/ui.js
index c11183a..5ca8100 100644
--- a/src/editor/ui.js
+++ b/src/editor/ui.js
@@ -4,9 +4,7 @@ import {Files} from './files.js'
 import {CallTree} from './calltree.js'
 import {Logs} from './logs.js'
 import {IO_Cache} from './io_cache.js'
-import {Eval} from './eval.js'
 import {el} from './domutils.js'
-import {FLAGS} from '../feature_flags.js'
 
 export class UI {
   constructor(container, state){
@@ -20,12 +18,8 @@ export class UI {
     this.debugger = {}
 
     container.appendChild(
-      (this.root = el('div', 
-          'root ' + (FLAGS.embed_value_explorer ? 'embed_value_explorer' : ''),
+      (this.root = el('div', 'root',
         this.editor_container = el('div', 'editor_container'),
-        FLAGS.embed_value_explorer
-          ? null
-          : (this.eval_container = el('div', {class: 'eval'})),
         el('div', 'bottom', 
           this.debugger_container = el('div', 'debugger',
             this.debugger_loaded = el('div', 'debugger_wrapper', 
@@ -173,17 +167,6 @@ export class UI {
       }
     })
 
-    if(!FLAGS.embed_value_explorer) {
-      this.eval = new Eval(this, this.eval_container)
-    } else {
-      // Stub
-      this.eval = {
-        show_value_or_error(){},
-        clear_value_or_error(){},
-        focus_value_or_error(){},
-      }
-    }
-
     this.editor = new Editor(this, this.editor_container)
 
     this.calltree = new CallTree(this, this.debugger.calltree)
diff --git a/src/effects.js b/src/effects.js
index 41692e8..0bd5e50 100644
--- a/src/effects.js
+++ b/src/effects.js
@@ -6,7 +6,6 @@ import {
   get_deferred_calls
 } from './calltree.js'
 import {current_cursor_position} from './calltree.js'
-import {FLAGS} from './feature_flags.js'
 import {exec, FILES_ROOT} from './index.js'
 
 // Imports in the context of `run_window`, so global variables in loaded
@@ -221,7 +220,6 @@ export const render_common_side_effects = (prev, next, command, ui) => {
       } else {
         // Rerender entire calltree
         ui.render_debugger(next)
-        ui.eval.clear_value_or_error()
         clear_coloring(ui)
         render_coloring(ui, next)
         ui.logs.rerender_logs(next.logs)
@@ -255,14 +253,6 @@ export const render_common_side_effects = (prev, next, command, ui) => {
         ui.calltree.render_select_node(prev, next)
       } 
 
-      if(node_changed) {
-        if(!next.current_calltree_node.toplevel) {
-          ui.eval.show_value_or_error(next.current_calltree_node)
-        } else {
-          ui.eval.clear_value_or_error()
-        }
-      }
-
       if(prev.calltree_node_by_loc != next.calltree_node_by_loc) {
         render_coloring(ui, next)
       }
@@ -290,15 +280,11 @@ export const render_common_side_effects = (prev, next, command, ui) => {
 
   const selresult = next.selection_state?.result
   if(selresult != null && prev.selection_state?.result != selresult) {
-    if(FLAGS.embed_value_explorer) {
-      const node = next.selection_state.node
-      ui.editor.embed_value_explorer({
-        index: node.index + node.length, 
-        result: next.selection_state.result,
-      })
-    } else {
-      ui.eval.show_value_or_error(next.selection_state.result)
-    }
+    const node = next.selection_state.node
+    ui.editor.embed_value_explorer({
+      index: node.index + node.length, 
+      result: next.selection_state.result,
+    })
   }
 
   // Value explorer
diff --git a/src/feature_flags.js b/src/feature_flags.js
deleted file mode 100644
index 2bb7c21..0000000
--- a/src/feature_flags.js
+++ /dev/null
@@ -1,3 +0,0 @@
-export const FLAGS = {
-  embed_value_explorer: true,
-}