diff --git a/web/app/dashboard/page.tsx b/web/app/dashboard/page.tsx
index 4397669..abd620e 100644
--- a/web/app/dashboard/page.tsx
+++ b/web/app/dashboard/page.tsx
@@ -1,3 +1,66 @@
+'use client'
+
+import { useEffect, useState } from 'react'
+import { useRouter } from 'next/navigation'
+import { supabase } from '@/lib/supabase'
+import type { Session } from '@supabase/supabase-js'
+
 export default function DashboardPage() {
-    return <div>Dashboard — coming soon</div>
-}
\ No newline at end of file
+  const [session, setSession] = useState<Session | null>(null)
+  const [loading, setLoading] = useState(true)
+  const router = useRouter()
+
+  useEffect(() => {
+    supabase.auth.getSession().then(({ data: { session } }) => {
+      setSession(session)
+      setLoading(false)
+    })
+
+    const {
+      data: { subscription },
+    } = supabase.auth.onAuthStateChange((_event, session) => {
+      setSession(session)
+      setLoading(false)
+    })
+
+    return () => subscription.unsubscribe()
+  }, [])
+
+  useEffect(() => {
+    if (!loading && !session) {
+      router.push('/')
+    }
+  }, [loading, session, router])
+
+  const signOut = async () => {
+    await supabase.auth.signOut()
+  }
+
+  if (loading || !session) {
+    return (
+      <div className="flex flex-1 items-center justify-center">
+        <p className="text-zinc-500">Loading...</p>
+      </div>
+    )
+  }
+
+  return (
+    <div className="flex flex-col flex-1 p-8 gap-6">
+      <div className="flex items-center justify-between">
+        <h1 className="text-2xl font-bold">Dashboard</h1>
+        <div className="flex items-center gap-4">
+          <span className="text-zinc-500">
+            {session.user.user_metadata.user_name}
+          </span>
+          <button
+            onClick={signOut}
+            className="rounded-full border border-zinc-300 px-4 py-2 text-sm font-medium hover:bg-zinc-100 dark:border-zinc-700 dark:hover:bg-zinc-800 transition-colors"
+          >
+            Sign out
+          </button>
+        </div>
+      </div>
+      <p className="text-zinc-500">Your codescapes will appear here.</p>
+    </div>
+  )
+}
diff --git a/web/app/page.tsx b/web/app/page.tsx
index 3f36f7c..6ef8ea2 100644
--- a/web/app/page.tsx
+++ b/web/app/page.tsx
@@ -1,65 +1,77 @@
-import Image from "next/image";
+'use client'
+
+import { useEffect, useState } from 'react'
+import { useRouter } from 'next/navigation'
+import { supabase } from '@/lib/supabase'
+import type { Session } from '@supabase/supabase-js'
+import { importUserRepos } from '@/lib/repos'
 
 export default function Home() {
+  const [session, setSession] = useState<Session | null>(null)
+  const [loading, setLoading] = useState(true)
+  const router = useRouter()
+
+  useEffect(() => {
+    supabase.auth.getSession().then(({ data: { session } }) => {
+      setSession(session)
+      setLoading(false)
+    })
+
+    const {
+      data: { subscription },
+    } = supabase.auth.onAuthStateChange((event, session) => {
+      setSession(session)
+      setLoading(false)
+
+      if (event === 'SIGNED_IN' && session) {
+        const githubToken = session.provider_token
+        const userId = session.user.id
+        if (githubToken) {
+          setTimeout(() => {
+            void importUserRepos(githubToken, userId).catch((err) => {
+              console.error('importUserRepos failed:', err)
+            })
+          }, 0)
+        }
+      }
+    })
+
+    return () => subscription.unsubscribe()
+  }, [])
+
+  useEffect(() => {
+    if (!loading && session) {
+      router.push('/dashboard')
+    }
+  }, [loading, session, router])
+
+  const signInWithGitHub = async () => {
+    await supabase.auth.signInWithOAuth({
+      provider: 'github',
+      options: {
+        redirectTo: window.location.origin,
+      },
+    })
+  }
+
+  if (loading) {
+    return (
+      <div className="flex flex-1 items-center justify-center">
+        <p className="text-zinc-500">Loading...</p>
+      </div>
+    )
+  }
+
   return (
-    <div className="flex flex-col flex-1 items-center justify-center bg-zinc-50 font-sans dark:bg-black">
-      <main className="flex flex-1 w-full max-w-3xl flex-col items-center justify-between py-32 px-16 bg-white dark:bg-black sm:items-start">
-        <Image
-          className="dark:invert"
-          src="/next.svg"
-          alt="Next.js logo"
-          width={100}
-          height={20}
-          priority
-        />
-        <div className="flex flex-col items-center gap-6 text-center sm:items-start sm:text-left">
-          <h1 className="max-w-xs text-3xl font-semibold leading-10 tracking-tight text-black dark:text-zinc-50">
-            To get started, edit the page.tsx file.
-          </h1>
-          <p className="max-w-md text-lg leading-8 text-zinc-600 dark:text-zinc-400">
-            Looking for a starting point or more instructions? Head over to{" "}
-            <a
-              href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
-            >
-              Templates
-            </a>{" "}
-            or the{" "}
-            <a
-              href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
-            >
-              Learning
-            </a>{" "}
-            center.
-          </p>
-        </div>
-        <div className="flex flex-col gap-4 text-base font-medium sm:flex-row">
-          <a
-            className="flex h-12 w-full items-center justify-center gap-2 rounded-full bg-foreground px-5 text-background transition-colors hover:bg-[#383838] dark:hover:bg-[#ccc] md:w-[158px]"
-            href="https://vercel.com/new?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            <Image
-              className="dark:invert"
-              src="/vercel.svg"
-              alt="Vercel logomark"
-              width={16}
-              height={16}
-            />
-            Deploy Now
-          </a>
-          <a
-            className="flex h-12 w-full items-center justify-center rounded-full border border-solid border-black/[.08] px-5 transition-colors hover:border-transparent hover:bg-black/[.04] dark:border-white/[.145] dark:hover:bg-[#1a1a1a] md:w-[158px]"
-            href="https://nextjs.org/docs?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            Documentation
-          </a>
-        </div>
-      </main>
+    <div className="flex flex-col flex-1 items-center justify-center gap-8">
+      <h1 className="text-4xl font-bold">Codescape</h1>
+      <p className="text-zinc-500 text-lg">Visualize your code as a city</p>
+      <button
+        onClick={signInWithGitHub}
+        className="rounded-full bg-zinc-900 text-white px-6 py-3 font-medium hover:bg-zinc-700 dark:bg-white dark:text-black dark:hover:bg-zinc-200 transition-colors"
+      >
+        Sign in with GitHub
+      </button>
     </div>
-  );
+  )
 }
diff --git a/web/lib/repos.ts b/web/lib/repos.ts
new file mode 100644
index 0000000..045e705
--- /dev/null
+++ b/web/lib/repos.ts
@@ -0,0 +1,86 @@
+import { supabase } from './supabase'
+
+export async function importUserRepos(githubToken: string, userId: string) {
+  const response = await fetch('https://api.github.com/user/repos?per_page=100', {
+    headers: {
+      Authorization: `Bearer ${githubToken}`,
+      Accept: 'application/vnd.github.v3+json',
+    },
+  })
+
+  if (!response.ok) {
+    const errorBody = await response.text().catch(() => '')
+    throw new Error(
+      `Failed to fetch GitHub repositories: ${response.status} ${response.statusText}` +
+        (errorBody ? ` - ${errorBody}` : '')
+    )
+  }
+
+  const repos = await response.json()
+
+  if (!Array.isArray(repos)) {
+    throw new Error('Unexpected GitHub API response when listing repositories; expected an array.')
+  }
+
+  for (const repo of repos) {
+    const codescapeResponse = await fetch(
+      `https://api.github.com/repos/${repo.full_name}/contents/.codescape`,
+      {
+        headers: {
+          Authorization: `Bearer ${githubToken}`,
+          Accept: 'application/vnd.github.v3+json',
+        },
+      }
+    )
+
+    if (codescapeResponse.ok) {
+      const fileData = await codescapeResponse.json()
+
+      const rawContent =
+        typeof fileData?.content === 'string' ? fileData.content.replace(/\s+/g, '') : null
+      if (!rawContent) {
+        console.warn('Missing or invalid .codescape content for repo', repo.full_name)
+        continue
+      }
+
+      let cityState: unknown
+      try {
+        const decoded = atob(rawContent)
+        const parsed = JSON.parse(decoded)
+
+        if (parsed === null || typeof parsed !== 'object' || Array.isArray(parsed)) {
+          console.warn('Invalid .codescape JSON shape for repo', repo.full_name)
+          continue
+        }
+
+        cityState = parsed
+      } catch (error) {
+        console.error('Failed to decode/parse .codescape file for repo', repo.full_name, error)
+        continue
+      }
+
+      const { error } = await supabase.from('linked_repos').upsert(
+        {
+          user_id: userId,
+          repo_owner: repo.owner.login,
+          repo_name: repo.name,
+          is_public: !repo.private,
+          city_state: cityState,
+          last_synced_at: new Date().toISOString(),
+        },
+        {
+          onConflict: 'user_id, repo_owner, repo_name',
+        }
+      )
+
+      if (error) {
+        console.error('Failed to upsert linked_repos record', {
+          userId,
+          repoFullName: repo.full_name,
+          error,
+        })
+        throw error
+      }
+    }
+  }
+}
diff --git a/web/lib/supabase.ts b/web/lib/supabase.ts
new file mode 100644
index 0000000..8cc5a2a
--- /dev/null
+++ b/web/lib/supabase.ts
@@ -0,0 +1,14 @@
+import { createClient } from '@supabase/supabase-js'
+
+const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL
+const supabaseAnonKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY
+
+if (!supabaseUrl) {
+  throw new Error('Missing environment variable NEXT_PUBLIC_SUPABASE_URL')
+}
+
+if (!supabaseAnonKey) {
+  throw new Error('Missing environment variable NEXT_PUBLIC_SUPABASE_ANON_KEY')
+}
+
+export const supabase = createClient(supabaseUrl, supabaseAnonKey)
diff --git a/web/package-lock.json b/web/package-lock.json
index b598ee0..66c798d 100644
--- a/web/package-lock.json
+++ b/web/package-lock.json
@@ -8,6 +8,8 @@
       "name": "web",
       "version": "0.1.0",
       "dependencies": {
+        "@supabase/ssr": "^0.10.0",
+        "@supabase/supabase-js": "^2.102.1",
         "next": "16.2.2",
         "react": "19.2.4",
         "react-dom": "19.2.4"
@@ -1234,6 +1236,105 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@supabase/auth-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/auth-js/-/auth-js-2.102.1.tgz",
+      "integrity": "sha512-2uH2WB0H98TOGDtaFWhxIcR42Dro/VB7VDZanz/4bVJsqioIue1m3TUqu3xciDm2W9r+1LXQvYNsYbQfWmD+uQ==",
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "2.8.1"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@supabase/functions-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/functions-js/-/functions-js-2.102.1.tgz",
+      "integrity": "sha512-UcrcKTPnAIo+Yp9Jjq9XXwFbsmgRYY637mwka9ZjmTIWcX/xr1pote4OVvaGQycVY1KTiQgjMvpC0Q0yJhRq3w==",
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "2.8.1"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@supabase/phoenix": {
+      "version": "0.4.0",
+      "resolved": "https://registry.npmjs.org/@supabase/phoenix/-/phoenix-0.4.0.tgz",
+      "integrity": "sha512-RHSx8bHS02xwfHdAbX5Lpbo6PXbgyf7lTaXTlwtFDPwOIw64NnVRwFAXGojHhjtVYI+PEPNSWwkL90f4agN3bw==",
+      "license": "MIT"
+    },
+    "node_modules/@supabase/postgrest-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/postgrest-js/-/postgrest-js-2.102.1.tgz",
+      "integrity": "sha512-InLvXKAYf8BIqiv9jWOYudWB3rU8A9uMbcip5BQ5sLLNPrbO1Ekkr79OvlhZBgMNSppxVyC7wPPGzLxMcTZhlA==",
+      "license": "MIT",
+      "dependencies": {
+        "tslib": "2.8.1"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@supabase/realtime-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/realtime-js/-/realtime-js-2.102.1.tgz",
+      "integrity": "sha512-h2fCumib/v6u7XMwSPgxnpfimjX4xCEayUHrxWLC7UurfQjUZJ0pmJDgm6yj80DnUerxuulRghwm5zXYysFG/Q==",
+      "license": "MIT",
+      "dependencies": {
+        "@supabase/phoenix": "^0.4.0",
+        "@types/ws": "^8.18.1",
+        "tslib": "2.8.1",
+        "ws": "^8.18.2"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@supabase/ssr": {
+      "version": "0.10.0",
+      "resolved": "https://registry.npmjs.org/@supabase/ssr/-/ssr-0.10.0.tgz",
+      "integrity": "sha512-36jIu+DuKzg5EgA3fnH+zHvwASvpKcL4zPgmHoZaULroS5Q4mzeHcM69zJ0sXUHddO5IcHjQNZJ9Vyhl/DdbRw==",
+      "license": "MIT",
+      "dependencies": {
+        "cookie": "^1.0.2"
+      },
+      "peerDependencies": {
+        "@supabase/supabase-js": "^2.100.1"
+      }
+    },
+    "node_modules/@supabase/storage-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/storage-js/-/storage-js-2.102.1.tgz",
+      "integrity": "sha512-eCL9T4Xpe40nmKlkUJ7Zq/hk34db1xPiT0WL3Iv5MbJqHuCAe5TxhV8Rjqd6DNZrzjtfYObZtYl9jKJaHrivqw==",
+      "license": "MIT",
+      "dependencies": {
+        "iceberg-js": "^0.8.1",
+        "tslib": "2.8.1"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
+    "node_modules/@supabase/supabase-js": {
+      "version": "2.102.1",
+      "resolved": "https://registry.npmjs.org/@supabase/supabase-js/-/supabase-js-2.102.1.tgz",
+      "integrity": "sha512-bChxPVeLDnYN9M2d/u4fXsvylwSQG5grAl+HN8f+ZD9a9PuVU+Ru+xGmEsk+b9Iz3rJC9ZQnQUJYQ28fApdWYA==",
+      "license": "MIT",
+      "peer": true,
+      "dependencies": {
+        "@supabase/auth-js": "2.102.1",
+        "@supabase/functions-js": "2.102.1",
+        "@supabase/postgrest-js": "2.102.1",
+        "@supabase/realtime-js": "2.102.1",
+        "@supabase/storage-js": "2.102.1"
+      },
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
     "node_modules/@swc/helpers": {
       "version": "0.5.15",
       "resolved": "https://registry.npmjs.org/@swc/helpers/-/helpers-0.5.15.tgz",
@@ -1550,7 +1651,6 @@
       "version": "20.19.37",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-20.19.37.tgz",
       "integrity": "sha512-8kzdPJ3FsNsVIurqBs7oodNnCEVbni9yUEkaHbgptDACOPW04jimGagZ51E6+lXUwJjgnBw+hyko/lkFWCldqw==",
-      "dev": true,
       "license": "MIT",
       "dependencies": {
         "undici-types": "~6.21.0"
@@ -1577,6 +1677,15 @@
         "@types/react": "^19.2.0"
       }
     },
+    "node_modules/@types/ws": {
+      "version": "8.18.1",
+      "resolved": "https://registry.npmjs.org/@types/ws/-/ws-8.18.1.tgz",
+      "integrity": "sha512-ThVF6DCVhA8kUGy+aazFQ4kXQ7E1Ty7A3ypFOe0IcJV8O/M511G99AW24irKrW56Wt44yG9+ij8FaqoBGkuBXg==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@typescript-eslint/eslint-plugin": {
       "version": "8.58.0",
       "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.58.0.tgz",
@@ -2644,6 +2753,19 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/cookie": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-1.1.1.tgz",
+      "integrity": "sha512-ei8Aos7ja0weRpFzJnEA9UHJ/7XQmqglbRwnf2ATjcB9Wq874VKH9kfjjirM6UhU2/E5fFYadylyhFldcqSidQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=18"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/express"
+      }
+    },
     "node_modules/cross-spawn": {
       "version": "7.0.6",
       "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.6.tgz",
@@ -3933,6 +4055,15 @@
         "hermes-estree": "0.25.1"
       }
     },
+    "node_modules/iceberg-js": {
+      "version": "0.8.1",
+      "resolved": "https://registry.npmjs.org/iceberg-js/-/iceberg-js-0.8.1.tgz",
+      "integrity": "sha512-1dhVQZXhcHje7798IVM+xoo/1ZdVfzOMIc8/rgVSijRK38EDqOJoGula9N/8ZI5RD8QTxNQtK/Gozpr+qUqRRA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=20.0.0"
+      }
+    },
     "node_modules/ignore": {
       "version": "5.3.2",
       "resolved": "https://registry.npmjs.org/ignore/-/ignore-5.3.2.tgz",
@@ -6363,7 +6494,6 @@
       "version": "6.21.0",
       "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
       "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
-      "dev": true,
       "license": "MIT"
     },
     "node_modules/unrs-resolver": {
@@ -6557,6 +6687,27 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/ws": {
+      "version": "8.20.0",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-8.20.0.tgz",
+      "integrity": "sha512-sAt8BhgNbzCtgGbt2OxmpuryO63ZoDk/sqaB/znQm94T4fCEsy/yV+7CdC1kJhOU9lboAEU7R3kquuycDoibVA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">=10.0.0"
+      },
+      "peerDependencies": {
+        "bufferutil": "^4.0.1",
+        "utf-8-validate": ">=5.0.2"
+      },
+      "peerDependenciesMeta": {
+        "bufferutil": {
+          "optional": true
+        },
+        "utf-8-validate": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/yallist": {
       "version": "3.1.1",
       "resolved": "https://registry.npmjs.org/yallist/-/yallist-3.1.1.tgz",
diff --git a/web/package.json b/web/package.json
index 173ebf3..c3e4772 100644
--- a/web/package.json
+++ b/web/package.json
@@ -9,6 +9,8 @@
     "lint": "eslint"
   },
   "dependencies": {
+    "@supabase/ssr": "^0.10.0",
+    "@supabase/supabase-js": "^2.102.1",
     "next": "16.2.2",
     "react": "19.2.4",
     "react-dom": "19.2.4"