diff --git a/client/src/components/Infoview.tsx b/client/src/components/Infoview.tsx
index 0ae02fa..a1d8d2c 100644
--- a/client/src/components/Infoview.tsx
+++ b/client/src/components/Infoview.tsx
@@ -6,13 +6,16 @@ import * as monaco from 'monaco-editor/esm/vs/editor/editor.api.js'
 import * as ls from 'vscode-languageserver-protocol'
 import TacticState from './TacticState';
 import { useLeanClient } from '../connection';
+import { useAppDispatch } from '../hooks';
+import { levelCompleted, selectCompleted } from '../state/progress';
 
 // TODO: move into Lean 4 web
 function toLanguageServerPosition (pos: monaco.Position): ls.Position {
   return {line : pos.lineNumber - 1, character: pos.column - 1}
 }
 
-function Infoview({ editor, editorApi } : {editor: monaco.editor.IStandaloneCodeEditor, editorApi: EditorApi}) {
+function Infoview({ worldId, levelId, editor, editorApi } : {worldId: string, levelId: number, editor: monaco.editor.IStandaloneCodeEditor, editorApi: EditorApi}) {
+  const dispatch = useAppDispatch()
   const [rpcSession, setRpcSession] = useState<string>()
   const [goals, setGoals] = useState<any[]>(null)
   const [completed, setCompleted] = useState<boolean>(false)
@@ -74,7 +77,11 @@ function Infoview({ editor, editorApi } : {editor: monaco.editor.IStandaloneCode
         "position": pos
       }).then((res) => {
         // Check that there are no errors and no warnings
-        setCompleted(!res.some(({severity}) => severity <= 2))
+        const completed = !res.some(({severity}) => severity <= 2)
+        if (completed) {
+          dispatch(levelCompleted({world: worldId, level: levelId}))
+        }
+        setCompleted(completed)
         setGlobalDiagnostics(res)
       }).catch((err) => {
         console.error(err)
diff --git a/client/src/components/Level.tsx b/client/src/components/Level.tsx
index 915aebb..144fc33 100644
--- a/client/src/components/Level.tsx
+++ b/client/src/components/Level.tsx
@@ -176,7 +176,7 @@ function Level() {
           <Button disabled={levelId <= 1} component={RouterLink} to={`/world/${worldId}/level/${levelId - 1}`} sx={{ ml: 3, mt: 2, mb: 2 }} disableFocusRipple>Previous Level</Button>
           <Button disabled={levelId >= gameInfo.data?.worldSize[worldId]} component={RouterLink} to={`/world/${worldId}/level/${levelId + 1}`} sx={{ ml: 3, mt: 2, mb: 2 }} disableFocusRipple>Next Level</Button>
 
-          <Infoview key={worldId + "/Level" + levelId} editor={editor} editorApi={infoProvider?.getApi()} />
+          <Infoview key={worldId + "/Level" + levelId} worldId={worldId} levelId={levelId} editor={editor} editorApi={infoProvider?.getApi()} />
         </Grid>
       </Grid>
     </Box>
diff --git a/client/src/components/Welcome.tsx b/client/src/components/Welcome.tsx
index 01dd626..2caafd5 100644
--- a/client/src/components/Welcome.tsx
+++ b/client/src/components/Welcome.tsx
@@ -7,16 +7,28 @@ import '@fontsource/roboto/700.css';
 import cytoscape, { LayoutOptions } from 'cytoscape'
 import klay from 'cytoscape-klay';
 import { Link as RouterLink, useNavigate } from 'react-router-dom';
+import { useSelector } from 'react-redux';
 
 
 cytoscape.use( klay );
 
-import { Box, Typography, Button, CircularProgress, Grid } from '@mui/material';
+import { Box, Typography, Button, CircularProgress, Grid, selectClasses } from '@mui/material';
 import { useGetGameInfoQuery } from '../state/api';
 import { Link } from 'react-router-dom';
 import Markdown from './Markdown';
+import { selectCompleted } from '../state/progress';
 
 
+function LevelIcon({ worldId, levelId, position }) {
+  const completed = useSelector(selectCompleted(worldId,levelId))
+  // TODO: relative positioning?
+  return (
+    <Link to={`/world/${worldId}/level/${levelId}`} key={`/world/${worldId}/level/${levelId}`}>
+      <circle fill={completed ? "green" :"#aaa"} cx={position.x + Math.sin(levelId/5) * 9} cy={position.y - Math.cos(levelId/5) * 9} r="0.8" />
+    </Link>
+  )
+}
+
 function Welcome() {
   const navigate = useNavigate();
 
@@ -51,9 +63,7 @@ function Welcome() {
 
       for (let i = 1; i <= gameInfo.data.worldSize[id]; i++) {
         svgElements.push(
-          <Link to={`/world/${id}/level/${i}`} key={`/world/${id}/level/${i}`}>
-            <circle fill="#aaa" cx={position.x + Math.sin(i/5) * 9} cy={position.y - Math.cos(i/5) * 9} r="0.8" />
-          </Link>
+          <LevelIcon position={position} worldId={id} levelId={i} />
         )
       }
     }
diff --git a/client/src/state/progress.ts b/client/src/state/progress.ts
index fae1127..c91b8e6 100644
--- a/client/src/state/progress.ts
+++ b/client/src/state/progress.ts
@@ -2,29 +2,66 @@ import { createSlice } from '@reduxjs/toolkit'
 import type { PayloadAction } from '@reduxjs/toolkit'
 
 interface ProgressState {
-  code: {[world: string]: {[level: number]: string}}
+  level: {[world: string]: {[level: number]: LevelProgressState}}
 }
 
-const initialState = { code: {} } as ProgressState
+interface LevelProgressState {
+  code: string,
+  completed: boolean
+}
+
+const initialProgressState = { level: {} } as ProgressState
+const initalLevelProgressState = {code: "", completed: false} as LevelProgressState
+
+function addLevelProgress(state, action: PayloadAction<{world: string, level: number}>) {
+  if (!state.level[action.payload.world]) {
+    state.level[action.payload.world] = {}
+  }
+  if (!state.level[action.payload.world][action.payload.level]) {
+    state.level[action.payload.world][action.payload.level] = {...initalLevelProgressState}
+  }
+}
 
 export const progressSlice = createSlice({
   name: 'progress',
-  initialState,
+  initialState: initialProgressState,
   reducers: {
     codeEdited(state, action: PayloadAction<{world: string, level: number, code: string}>) {
-      if (!state.code[action.payload.world]) {
-        state.code[action.payload.world] = {}
-      }
-      state.code[action.payload.world][action.payload.level] = action.payload.code
+      addLevelProgress(state, action)
+      state.level[action.payload.world][action.payload.level].code = action.payload.code
+      state.level[action.payload.world][action.payload.level].completed = false
+    },
+    levelCompleted(state, action: PayloadAction<{world: string, level: number}>) {
+      addLevelProgress(state, action)
+      state.level[action.payload.world][action.payload.level].completed = true
     },
   }
 })
 
+export function selectLevel(world: string, level: number) {
+  return (state) =>{
+    if (!state.progress.level[world]) { return initalLevelProgressState }
+    if (!state.progress.level[world][level]) { return initalLevelProgressState }
+    return state.progress.level[world][level]
+  }
+}
+
 export function selectCode(world: string, level: number) {
   return (state) => {
-    if (!state.progress.code[world]) { return undefined }
-    return state.progress.code[world][level];
+    return selectLevel(world, level)(state).code
+  }
+}
+
+export function selectCompleted(world: string, level: number) {
+  return (state) => {
+    return selectLevel(world, level)(state).completed
+  }
+}
+
+export function selectProgress() {
+  return (state) => {
+    return state.progress
   }
 }
 
-export const { codeEdited } = progressSlice.actions
+export const { codeEdited, levelCompleted } = progressSlice.actions