diff --git a/flake.nix b/flake.nix
index b1ce508..9b586a7 100644
--- a/flake.nix
+++ b/flake.nix
@@ -7,12 +7,20 @@
     flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { nixpkgs, rust-overlay, flake-utils, ... }:
+  outputs = {
+    nixpkgs,
+    rust-overlay,
+    flake-utils,
+    ...
+  }:
     flake-utils.lib.eachDefaultSystem (system:
       let
         pkgs = import nixpkgs {
           inherit system;
-          overlays = [ (import rust-overlay) ];
+
+          overlays = [
+            rust-overlay.overlays.default
+          ];
         };
 
         rust = pkgs.rust-bin.stable.latest.default.override {
@@ -21,104 +29,236 @@
             "clippy"
           ];
         };
-      in {
+      in
+      {
         devShells.default = pkgs.mkShell {
           packages = with pkgs; [
             rust
 
+            # Database
             postgresql
-            postgis
-
+            postgresqlPackages.postgis
             sqlx-cli
 
+            # GIS
             gdal
             geos
             proj
 
+            # Build dependencies
             pkg-config
             openssl
           ];
 
           shellHook = ''
+            set -e
+
+            # ------------------------------------------------------------
+            # Local PostgreSQL
+            # ------------------------------------------------------------
+
             export PGDATA="$PWD/.pgdata"
             export PGHOST="$PWD/.pgsocket"
             export PGPORT="5433"
+
             export PGDATABASE="county_sprints"
             export PGUSER="county_sprints"
 
             mkdir -p "$PGHOST"
 
+            # ------------------------------------------------------------
+            # Initialise PostgreSQL cluster
+            # ------------------------------------------------------------
+
             if [ ! -f "$PGDATA/PG_VERSION" ]; then
-              echo "initialising PostgreSQL..."
+              echo
+              echo "==> Initialising local PostgreSQL cluster"
 
               initdb \
                 --auth=trust \
                 --no-locale \
-                "$PGDATA" >/dev/null
-
-              cat >> "$PGDATA/postgresql.conf" <<PGEOF
-listen_addresses = ''
-port = 5433
-unix_socket_directories = '$PGHOST'
-PGEOF
+                --encoding=UTF8 \
+                "$PGDATA" \
+                >/dev/null
             fi
 
-            if ! pg_ctl -D "$PGDATA" status >/dev/null 2>&1; then
+            # ------------------------------------------------------------
+            # Configure PostgreSQL
+            # ------------------------------------------------------------
+
+            # Always write our development settings. This means changing
+            # the flake also updates an already existing local cluster.
+            cat > "$PGDATA/postgresql.conf" <<EOF
+listen_addresses = '' + "''" + ''
+port = 5433
+unix_socket_directories = '$PGHOST'
+EOF
+
+            # ------------------------------------------------------------
+            # Start PostgreSQL
+            # ------------------------------------------------------------
+
+            if ! pg_ctl \
+              -D "$PGDATA" \
+              status \
+              >/dev/null 2>&1
+            then
+              echo
+              echo "==> Starting local PostgreSQL"
+
               pg_ctl \
                 -D "$PGDATA" \
                 -o "-k $PGHOST -p $PGPORT" \
                 -l "$PGDATA/postgresql.log" \
-                start >/dev/null
+                start \
+                >/dev/null
+
+              # Wait until PostgreSQL actually accepts connections.
+              for i in $(seq 1 30); do
+                if pg_isready \
+                  -h "$PGHOST" \
+                  -p "$PGPORT" \
+                  >/dev/null 2>&1
+                then
+                  break
+                fi
+
+                sleep 0.2
+              done
             fi
 
+            # ------------------------------------------------------------
+            # Create application role
+            # ------------------------------------------------------------
+
             if ! psql \
               -h "$PGHOST" \
               -p "$PGPORT" \
               -d postgres \
-              -tAc "SELECT 1 FROM pg_roles WHERE rolname='$PGUSER'" |
+              -tAc \
+              "SELECT 1
+                 FROM pg_roles
+                WHERE rolname = '$PGUSER'" |
               grep -q 1
             then
-              createuser \
-                -h "$PGHOST" \
-                -p "$PGPORT" \
-                "$PGUSER"
-            fi
+              echo
+              echo "==> Creating PostgreSQL role '$PGUSER'"
 
-            if ! psql \
-              -h "$PGHOST" \
-              -p "$PGPORT" \
-              -d postgres \
-              -tAc "SELECT 1 FROM pg_database WHERE datname='$PGDATABASE'" |
-              grep -q 1
-            then
-              createdb \
-                -h "$PGHOST" \
-                -p "$PGPORT" \
-                -O "$PGUSER" \
-                "$PGDATABASE"
-            fi
-
-            if ! psql \
-              -h "$PGHOST" \
-              -p "$PGPORT" \
-              -d "$PGDATABASE" \
-              -tAc "SELECT 1 FROM pg_extension WHERE extname='postgis'" |
-              grep -q 1
-            then
               psql \
                 -h "$PGHOST" \
                 -p "$PGPORT" \
-                -d "$PGDATABASE" \
-                -c "CREATE EXTENSION postgis;" >/dev/null
+                -d postgres \
+                -v ON_ERROR_STOP=1 \
+                -c \
+                "CREATE ROLE \"$PGUSER\" LOGIN;"
             fi
 
+            # ------------------------------------------------------------
+            # Create application database
+            # ------------------------------------------------------------
+
+            if ! psql \
+              -h "$PGHOST" \
+              -p "$PGPORT" \
+              -d postgres \
+              -tAc \
+              "SELECT 1
+                 FROM pg_database
+                WHERE datname = '$PGDATABASE'" |
+              grep -q 1
+            then
+              echo
+              echo "==> Creating PostgreSQL database '$PGDATABASE'"
+
+              psql \
+                -h "$PGHOST" \
+                -p "$PGPORT" \
+                -d postgres \
+                -v ON_ERROR_STOP=1 \
+                -c \
+                "CREATE DATABASE \"$PGDATABASE\" OWNER \"$PGUSER\";"
+            fi
+
+            # ------------------------------------------------------------
+            # Make sure the application role owns the database
+            # ------------------------------------------------------------
+
+            psql \
+              -h "$PGHOST" \
+              -p "$PGPORT" \
+              -d postgres \
+              -v ON_ERROR_STOP=1 \
+              -c \
+              "ALTER DATABASE \"$PGDATABASE\" OWNER TO \"$PGUSER\";" \
+              >/dev/null
+
+            # ------------------------------------------------------------
+            # PostGIS
+            # ------------------------------------------------------------
+
+            echo
+            echo "==> Checking PostGIS"
+
+            psql \
+              -h "$PGHOST" \
+              -p "$PGPORT" \
+              -d "$PGDATABASE" \
+              -v ON_ERROR_STOP=1 \
+              -c \
+              "CREATE EXTENSION IF NOT EXISTS postgis;" \
+              >/dev/null
+
+            # ------------------------------------------------------------
+            # DATABASE_URL for sqlx / application
+            # ------------------------------------------------------------
+
             export DATABASE_URL="postgresql://$PGUSER@/$PGDATABASE?host=$PGHOST&port=$PGPORT"
 
+            # ------------------------------------------------------------
+            # Environment
+            # ------------------------------------------------------------
+
+            export RUST_BACKTRACE=1
+
+            if [ -z "''${RUST_LOG:-}" ]; then
+              export RUST_LOG="info"
+            fi
+
+            # ------------------------------------------------------------
+            # Info
+            # ------------------------------------------------------------
+
             echo
-            echo "========================================"
-            echo " county-sprints development environment"
-            echo "========================================"
-            echo "DATABASE_URL=$DATABASE_URL"
+            echo "=============================================="
+            echo " Landkreis-Sprints development environment"
+            echo "=============================================="
+            echo
+            echo "Rust:"
+            rustc --version
+            echo
+            echo "PostgreSQL:"
+            psql \
+              -h "$PGHOST" \
+              -p "$PGPORT" \
+              -d "$PGDATABASE" \
+              -tAc "SELECT version();" |
+              sed 's/^/  /'
+            echo
+            echo "PostGIS:"
+            psql \
+              -h "$PGHOST" \
+              -p "$PGPORT" \
+              -d "$PGDATABASE" \
+              -tAc "SELECT PostGIS_Full_Version();" |
+              sed 's/^/  /'
+            echo
+            echo "DATABASE_URL:"
+            echo "  $DATABASE_URL"
+            echo
+            echo "Run:"
+            echo "  sqlx migrate run"
+            echo "  cargo test"
+            echo "  cargo run"
             echo
           '';
         };