diff --git a/.gitea/workflows/registry.yml b/.gitea/workflows/registry.yml
new file mode 100644
index 0000000..7f76155
--- /dev/null
+++ b/.gitea/workflows/registry.yml
@@ -0,0 +1,67 @@
+name: release-tag
+on:
+  push:
+    branches:
+      - 'main'
+jobs:
+  release-image:
+    runs-on: ubuntu-fast
+    env:
+      DOCKER_ORG: ${{ vars.DOCKER_ORG }}
+      DOCKER_LATEST: latest
+      RUNNER_TOOL_CACHE: /toolcache
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker BuildX
+        uses: docker/setup-buildx-action@v2
+        with: # replace it with your local IP
+          config-inline: |
+            [registry."${{ vars.DOCKER_REGISTRY }}"] 
+              http = true
+              insecure = true            
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          registry: ${{ vars.DOCKER_REGISTRY }} # replace it with your local IP
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+          
+      - name: Get Meta
+        id: meta
+        run: |
+          echo REPO_NAME=$(echo ${GITHUB_REPOSITORY} | awk -F"/" '{print $2}') >> $GITHUB_OUTPUT
+          echo REPO_VERSION=$(git describe --tags --always | sed 's/^v//') >> $GITHUB_OUTPUT                
+
+      - name: Build and push
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          file: ./Dockerfile
+          build-args: |
+            CONTENT_REPO=https://git.send.nrw/b1tsblog/blogcontent.git
+            CONTENT_REF=main
+          platforms: |
+            linux/amd64                       
+          push: true
+          tags: | # replace it with your local IP and tags
+            ${{ vars.DOCKER_REGISTRY }}/${{ env.DOCKER_ORG }}/${{ steps.meta.outputs.REPO_NAME }}:${{ steps.meta.outputs.REPO_VERSION }}
+            ${{ vars.DOCKER_REGISTRY }}/${{ env.DOCKER_ORG }}/${{ steps.meta.outputs.REPO_NAME }}:${{ env.DOCKER_LATEST }}
+      - name: Build and push StarCitizen
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          file: ./Dockerfile
+          build-args: |
+            CONTENT_REPO=https://git.send.nrw/b1tsblog/sccontent.git
+            CONTENT_REF=main
+          platforms: |
+            linux/amd64                       
+          push: true
+          tags: | # replace it with your local IP and tags
+            ${{ vars.DOCKER_REGISTRY }}/${{ env.DOCKER_ORG }}/${{ steps.meta.outputs.REPO_NAME }}:sc-${{ env.DOCKER_LATEST }}
\ No newline at end of file
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..2ffc999
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,26 @@
+# -------- Dockerfile (Multi-Stage Build) --------
+# 1. Builder-Stage
+FROM golang:1.24-alpine AS builder
+
+WORKDIR /app
+COPY go.* ./
+RUN go mod download
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o /bin/ipblock-api
+
+# 2. Runtime-Stage
+FROM alpine:3.20
+
+# HTTPS-Callouts in Alpine brauchen ca-certificates
+RUN apk add --no-cache ca-certificates
+
+COPY --from=builder /bin/ipblock-api /bin/ipblock-api
+
+# Default listens on :8080 – siehe main.go
+EXPOSE 8080
+
+# Environment defaults; können per compose überschrieben werden
+ENV REDIS_ADDR=redis:6379 \
+    TTL_HOURS=720
+
+ENTRYPOINT [\"/bin/ipblock-api\"]
diff --git a/compose.yml b/compose.yml
new file mode 100644
index 0000000..70c791a
--- /dev/null
+++ b/compose.yml
@@ -0,0 +1,30 @@
+# -------- docker-compose.yml --------
+version: "3.9"
+
+services:
+  api:
+    build: .
+    container_name: ipblock-api
+    depends_on:
+      - redis
+    environment:
+      # Beispiel – mehrere Listen in einer Kategorie „spam“
+      BLOCKLIST_SOURCES: |
+        spam:https://ipv64.net/blocklists/ipv64_blocklist_firehole_l1.txt|https://rules.emergingthreats.net/blocklist/compromised-ips.txt
+      # Redis-Adresse schon per Docker-Netzwerk korrekt:
+      REDIS_ADDR: redis:6379
+      TTL_HOURS: "720"
+    ports:
+      - "8080:8080"   # <host>:<container>
+    restart: unless-stopped
+
+  redis:
+    image: redis:7-alpine
+    container_name: ipblock-redis
+    command: ["redis-server", "--save", "", "--appendonly", "no"]  # reine In-Memory-Instanz
+    #volumes:
+      #- redis-data:/data   # falls du doch Persistence willst
+    restart: unless-stopped
+
+#volumes:
+  #redis-data:
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..7b66121
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,9 @@
+module git.send.nrw/sendnrw/flod
+
+go 1.24.3
+
+require (
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	github.com/redis/go-redis/v9 v9.10.0 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..0d570ba
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,6 @@
+github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
+github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
+github.com/redis/go-redis/v9 v9.10.0 h1:FxwK3eV8p/CQa0Ch276C7u2d0eNC9kCmAYQ7mCXCzVs=
+github.com/redis/go-redis/v9 v9.10.0/go.mod h1:huWgSWd8mW6+m0VPhJjSSQ+d6Nh1VICQ6Q5lHuCH/Iw=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..5b20850
--- /dev/null
+++ b/main.go
@@ -0,0 +1,329 @@
+package main
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"net/netip"
+	"os"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+// -----------------------------------------------------------------------------
+// CONFIGURATION
+// -----------------------------------------------------------------------------
+
+type Source struct {
+	Category string   // e.g. "spam", "tor", "malware"
+	URL      []string // one or many URLs that belong to the same category
+}
+
+type Config struct {
+	RedisAddr string
+	Sources   []Source // each Source now groups URLs per category
+	TTLHours  int      // Redis TTL for block entries
+}
+
+func loadConfig() Config {
+	// --- default one‑category fallback --------------------------------------
+	srcs := []Source{{
+		Category: "generic",
+		URL:      []string{"https://ipv64.net/blocklists/ipv64_blocklist_firehole_l1.txt"},
+	}}
+
+	/*
+	   ENV syntax supporting multiple URLs per category:
+
+	   BLOCKLIST_SOURCES="spam:https://a.net|https://b.net,tor:https://c.net;https://d.net"
+
+	   – categories separated by comma
+	   – URLs inside category separated by | or ;
+	*/
+
+	if env := os.Getenv("BLOCKLIST_SOURCES"); env != "" {
+		srcs = nil // override default
+		for _, spec := range strings.Split(env, ",") {
+			spec = strings.TrimSpace(spec)
+			if spec == "" {
+				continue
+			}
+			parts := strings.SplitN(spec, ":", 2)
+			if len(parts) != 2 {
+				continue // malformed fragment
+			}
+			cat := strings.TrimSpace(parts[0])
+			rawURLs := strings.FieldsFunc(parts[1], func(r rune) bool { return r == '|' || r == ';' })
+			var urls []string
+			for _, u := range rawURLs {
+				if u = strings.TrimSpace(u); u != "" {
+					urls = append(urls, u)
+				}
+			}
+			if len(urls) > 0 {
+				srcs = append(srcs, Source{Category: cat, URL: urls})
+			}
+		}
+	}
+
+	ttl := 720 // 30 days
+	if env := os.Getenv("TTL_HOURS"); env != "" {
+		fmt.Sscanf(env, "%d", &ttl)
+	}
+
+	return Config{
+		RedisAddr: getenv("REDIS_ADDR", "localhost:6379"),
+		Sources:   srcs,
+		TTLHours:  ttl,
+	}
+}
+
+func getenv(k, def string) string {
+	if v := os.Getenv(k); v != "" {
+		return v
+	}
+	return def
+}
+
+// -----------------------------------------------------------------------------
+// REDIS KEY HELPERS
+// -----------------------------------------------------------------------------
+
+func keyBlock(cat string, p netip.Prefix) string { return "bl:" + cat + ":" + p.String() }
+func keyWhite(a netip.Addr) string               { return "wl:" + a.String() }
+
+// -----------------------------------------------------------------------------
+// IN‑MEMORY RANGER – per‑category CIDR map
+// -----------------------------------------------------------------------------
+
+type Ranger struct {
+	mu     sync.RWMutex
+	blocks map[string]map[netip.Prefix]struct{} // cat → set(prefix)
+	whites map[netip.Addr]struct{}
+}
+
+func newRanger() *Ranger {
+	return &Ranger{
+		blocks: make(map[string]map[netip.Prefix]struct{}),
+		whites: make(map[netip.Addr]struct{}),
+	}
+}
+
+func (r *Ranger) resetBlocks(m map[string]map[netip.Prefix]struct{}) {
+	r.mu.Lock()
+	r.blocks = m
+	r.mu.Unlock()
+}
+
+func (r *Ranger) addWhite(a netip.Addr) {
+	r.mu.Lock()
+	r.whites[a] = struct{}{}
+	r.mu.Unlock()
+}
+
+// blockedInCats – returns slice of categories in which IP is blocked
+func (r *Ranger) blockedInCats(a netip.Addr, cats []string) []string {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+
+	if _, ok := r.whites[a]; ok {
+		return nil
+	}
+
+	if len(cats) == 0 {
+		for c := range r.blocks {
+			cats = append(cats, c)
+		}
+	}
+
+	var res []string
+	for _, cat := range cats {
+		if m, ok := r.blocks[cat]; ok {
+			for p := range m {
+				if p.Contains(a) {
+					res = append(res, cat)
+					break
+				}
+			}
+		}
+	}
+	sort.Strings(res)
+	return res
+}
+
+// -----------------------------------------------------------------------------
+// SYNC WORKER – fetch lists → Redis + Ranger
+// -----------------------------------------------------------------------------
+
+func syncOnce(ctx context.Context, cfg Config, rdb *redis.Client, ranger *Ranger) error {
+	expiry := time.Duration(cfg.TTLHours) * time.Hour
+	newBlocks := make(map[string]map[netip.Prefix]struct{})
+
+	for _, src := range cfg.Sources {
+		for _, url := range src.URL {
+			if err := processURL(ctx, url, func(p netip.Prefix) {
+				if _, ok := newBlocks[src.Category]; !ok {
+					newBlocks[src.Category] = make(map[netip.Prefix]struct{})
+				}
+				newBlocks[src.Category][p] = struct{}{}
+				_ = rdb.Set(ctx, keyBlock(src.Category, p), "1", expiry).Err()
+			}); err != nil {
+				return err
+			}
+		}
+	}
+
+	ranger.resetBlocks(newBlocks)
+	return nil
+}
+
+func processURL(ctx context.Context, url string, cb func(netip.Prefix)) error {
+	req, _ := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("%s -> %s", url, resp.Status)
+	}
+	return parseStream(resp.Body, cb)
+}
+
+func parseStream(r io.Reader, cb func(netip.Prefix)) error {
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		line := strings.TrimSpace(s.Text())
+		if line == "" || strings.HasPrefix(line, "#") {
+			continue
+		}
+		if p, err := netip.ParsePrefix(line); err == nil {
+			cb(p)
+		}
+	}
+	return s.Err()
+}
+
+// -----------------------------------------------------------------------------
+// HTTP SERVER
+// -----------------------------------------------------------------------------
+
+type Server struct {
+	cfg    Config
+	ranger *Ranger
+	rdb    *redis.Client
+}
+
+func (s *Server) routes() http.Handler {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/check/", s.handleCheck)       // GET /check/<ip>?cats=spam,tor
+	mux.HandleFunc("/whitelist", s.handleAddWhite) // POST {"ip":"1.2.3.4"}
+	mux.HandleFunc("/categories", s.handleCats)    // GET all categories
+	return mux
+}
+
+func (s *Server) handleCheck(w http.ResponseWriter, r *http.Request) {
+	ipStr := strings.TrimPrefix(r.URL.Path, "/check/")
+	addr, err := netip.ParseAddr(ipStr)
+	if err != nil {
+		http.Error(w, "bad ip", http.StatusBadRequest)
+		return
+	}
+
+	var cats []string
+	if q := strings.TrimSpace(r.URL.Query().Get("cats")); q != "" {
+		cats = strings.Split(q, ",")
+	}
+
+	blocked := s.ranger.blockedInCats(addr, cats)
+	writeJSON(w, map[string]any{
+		"ip":         ipStr,
+		"blocked":    len(blocked) > 0,
+		"categories": blocked,
+	})
+}
+
+func (s *Server) handleAddWhite(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "POST only", http.StatusMethodNotAllowed)
+		return
+	}
+	var body struct {
+		IP string `json:"ip"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+		http.Error(w, "bad json", 400)
+		return
+	}
+	addr, err := netip.ParseAddr(strings.TrimSpace(body.IP))
+	if err != nil {
+		http.Error(w, "bad ip", 400)
+		return
+	}
+	if err := s.rdb.Set(r.Context(), keyWhite(addr), "1", 0).Err(); err != nil {
+		http.Error(w, "redis", 500)
+		return
+	}
+	s.ranger.addWhite(addr)
+	writeJSON(w, map[string]string{"status": "whitelisted"})
+}
+
+func (s *Server) handleCats(w http.ResponseWriter, _ *http.Request) {
+	s.ranger.mu.RLock()
+	cats := make([]string, 0, len(s.ranger.blocks))
+	for c := range s.ranger.blocks {
+		cats = append(cats, c)
+	}
+	s.ranger.mu.RUnlock()
+	sort.Strings(cats)
+	writeJSON(w, map[string]any{"categories": cats})
+}
+
+func writeJSON(w http.ResponseWriter, v any) {
+	w.Header().Set("Content-Type", "application/json")
+	_ = json.NewEncoder(w).Encode(v)
+}
+
+// -----------------------------------------------------------------------------
+// MAIN
+// -----------------------------------------------------------------------------
+
+func main() {
+	cfg := loadConfig()
+
+	rdb := redis.NewClient(&redis.Options{Addr: cfg.RedisAddr})
+	ctx := context.Background()
+	if err := rdb.Ping(ctx).Err(); err != nil {
+		log.Fatalf("redis: %v", err)
+	}
+
+	ranger := newRanger()
+	if err := syncOnce(ctx, cfg, rdb, ranger); err != nil {
+		log.Println("initial sync:", err)
+	}
+
+	go func() {
+		ticker := time.NewTicker(6 * time.Hour)
+		defer ticker.Stop()
+		for range ticker.C {
+			if err := syncOnce(ctx, cfg, rdb, ranger); err != nil {
+				log.Println("sync:", err)
+			}
+		}
+	}()
+
+	srv := &Server{cfg: cfg, ranger: ranger, rdb: rdb}
+	log.Println("listening on :8080")
+	if err := http.ListenAndServe(":8080", srv.routes()); err != nil && !errors.Is(err, http.ErrServerClosed) {
+		log.Fatal(err)
+	}
+}