diff --git a/frontend/static/openapi.yaml b/frontend/static/openapi.yaml
index d837a5d..798ffb1 100644
--- a/frontend/static/openapi.yaml
+++ b/frontend/static/openapi.yaml
@@ -10,7 +10,7 @@ info:
   license:
     name: Apache 2.0
     url: http://www.apache.org/licenses/LICENSE-2.0.html
-  version: 0.15.1
+  version: dev
 servers:
   - url: https://columbus.elmasy.com
 tags:
@@ -306,6 +306,42 @@ paths:
         '504':
           description: Gateway Timeout. Upstream response takes too long.
 
+  /api/insert/{domain}:
+    put:
+      tags:
+        - domain
+      operationId: PutAPIInsert
+      summary: Insert domain into the database.
+      description: |
+        This endpoint technically suggest a domain to the server.
+        
+        It is required to have at least one valid DNS record for the domain to insert (eg.: `A` or `AAAA`).
+        The domain is sent to an underlying channel, so returns fast, but the client will not get informed about the result.
+        If the underlying channel is full, hangs until there is free space to send.
+        
+        This endpoint uses blacklist and rate limiter to prevent garbage and resource exhaustion
+        (eg.: sending invalid domain results a block for some time).
+      parameters:
+        - name: domain
+          in: path
+          description: Domain to insert.
+          required: true
+          schema:
+            type: string
+      responses:
+        '200':
+          description: OK
+        '400':
+          description: Invalid domain.
+        '403':
+          description: Client IP blocked.
+        '500':
+          description: Internal Server Error.
+        '502':
+          description: Bad Gateway. Upstream failed.
+        '504':
+          description: Gateway Timeout. Upstream response takes too long.
+          
   /api/stat:
     get:
       tags:
diff --git a/server/config/config.go b/server/config/config.go
index 8479ca7..2e1789b 100644
--- a/server/config/config.go
+++ b/server/config/config.go
@@ -6,6 +6,7 @@ import (
 	"runtime"
 	"time"
 
+	"github.com/elmasy-com/elnet/blocklist"
 	"github.com/elmasy-com/elnet/dns"
 	"gopkg.in/yaml.v3"
 )
@@ -20,6 +21,10 @@ type conf struct {
 	DNSServers     []string `yaml:"DNSServers"`
 	DomainWorker   int      `yaml:"DomainWorker"`
 	DomainBuffer   int      `yaml:"DomainBuffer"`
+	InsertWorker   int      `yaml:"InsertWorker"`
+	InsertBuffer   int      `yaml:"InsertBuffer"`
+	BlocklistSize  int      `yaml:"BlocklistSize"`
+	BlockTime      int      `yaml:"BlockTime"`
 }
 
 var (
@@ -32,6 +37,11 @@ var (
 	DNSServers     []string
 	DomainWorker   int
 	DomainBuffer   int
+	InsertWorker   int
+	InsertBuffer   int
+	BlocklistSize  int
+	BlockTime      time.Duration
+	Blocklist      *blocklist.Blocklist
 )
 
 // Parse parses the config file in path and gill the global variables.
@@ -87,5 +97,31 @@ func Parse(path string) error {
 
 	DomainBuffer = c.DomainBuffer
 
+	if c.InsertWorker == 0 {
+		c.InsertWorker = runtime.NumCPU()
+	}
+
+	InsertWorker = c.InsertWorker
+
+	if c.InsertBuffer == 0 {
+		c.InsertBuffer = 10000
+	}
+
+	InsertBuffer = c.InsertBuffer
+
+	if c.BlocklistSize == 0 {
+		c.BlocklistSize = 1000
+	}
+
+	BlocklistSize = c.BlocklistSize
+
+	if c.BlockTime == 0 {
+		c.BlockTime = 600
+	}
+
+	BlockTime = time.Duration(c.BlockTime) * time.Second
+
+	Blocklist = blocklist.NewBlocklist(BlockTime, int64(BlocklistSize))
+
 	return nil
 }
diff --git a/server/route/api/insert/insert.go b/server/route/api/insert/insert.go
new file mode 100644
index 0000000..bc09a16
--- /dev/null
+++ b/server/route/api/insert/insert.go
@@ -0,0 +1,33 @@
+package insert
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/elmasy-com/columbus/db"
+	"github.com/elmasy-com/columbus/server/config"
+	"github.com/elmasy-com/elnet/dns"
+	"github.com/elmasy-com/elnet/validator"
+	"github.com/gin-gonic/gin"
+)
+
+func PutApiInsert(c *gin.Context) {
+
+	if config.Blocklist.IsBlocked(c.ClientIP()) {
+		c.Status(http.StatusForbidden)
+		return
+	}
+
+	d := dns.Clean(c.Param("domain"))
+
+	if !validator.Domain(d) {
+		config.Blocklist.Block(c.ClientIP())
+		c.Error(fmt.Errorf("invalid domain: %s", d))
+		c.Status(http.StatusBadRequest)
+		return
+	}
+
+	db.UpdaterChan <- db.UpdateableDomain{Domain: d, Type: db.InsertNewDomain}
+
+	c.Status(http.StatusOK)
+}
diff --git a/server/server.conf b/server/server.conf
index 0f0f839..1928f6a 100644
--- a/server/server.conf
+++ b/server/server.conf
@@ -24,4 +24,10 @@ DNSServers: ["upd://8.8.8.8:53", "udp://8.8.4.4:53", "udp://1.1.1.1:53", "udp://
 DomainWorker: 4
 
 # Buffer for record updater (default: 1000)
-DomainBuffer: 10000
\ No newline at end of file
+DomainBuffer: 10000
+
+# Size of the blocklist (default: 1000)
+BlocklistSize: 1000
+
+# Number of seconds to block remote IP on bad behaviour (default: 600)
+BlockTime: 600
\ No newline at end of file
diff --git a/server/server.go b/server/server.go
index 580ced2..56299bd 100644
--- a/server/server.go
+++ b/server/server.go
@@ -14,6 +14,7 @@ import (
 	"github.com/elmasy-com/columbus/server/config"
 	"github.com/elmasy-com/columbus/server/route/api"
 	"github.com/elmasy-com/columbus/server/route/api/history"
+	"github.com/elmasy-com/columbus/server/route/api/insert"
 	"github.com/elmasy-com/columbus/server/route/api/lookup"
 	"github.com/elmasy-com/columbus/server/route/api/starts"
 	"github.com/elmasy-com/columbus/server/route/api/statistics"
@@ -91,6 +92,8 @@ func ServerRun() error {
 	router.GET("/api/tools/subdomain/:fqdn", tools.ToolsSubdomainGet)
 	router.GET("/api/tools/isvalid/:fqdn", tools.ToolsIsValidGet)
 
+	router.PUT("/api/insert/:domain", insert.PutApiInsert)
+
 	// Redirect to /search/:domain
 	router.GET("/lookup/:domain", lookup.RedirectLookup)