diff --git a/backend/src/main/kotlin/com/lightswitch/infrastructure/database/entity/SdkClient.kt b/backend/src/main/kotlin/com/lightswitch/infrastructure/database/entity/SdkClient.kt
index 44b597b..c3c8c4f 100644
--- a/backend/src/main/kotlin/com/lightswitch/infrastructure/database/entity/SdkClient.kt
+++ b/backend/src/main/kotlin/com/lightswitch/infrastructure/database/entity/SdkClient.kt
@@ -2,9 +2,12 @@ package com.lightswitch.infrastructure.database.entity
 
 import jakarta.persistence.Column
 import jakarta.persistence.Entity
+import jakarta.persistence.FetchType
 import jakarta.persistence.GeneratedValue
 import jakarta.persistence.GenerationType
 import jakarta.persistence.Id
+import jakarta.persistence.JoinColumn
+import jakarta.persistence.ManyToOne
 import java.time.Instant
 
 @Entity
@@ -17,4 +20,7 @@ class SdkClient(
     @Column(nullable = false)
     val sdkType: String,
     var connectedAt: Instant,
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "user_id", nullable = false)
+    val user: User,
 ) : BaseEntity()
diff --git a/backend/src/main/kotlin/com/lightswitch/infrastructure/database/model/SdkType.kt b/backend/src/main/kotlin/com/lightswitch/infrastructure/database/model/SdkType.kt
new file mode 100644
index 0000000..20a134a
--- /dev/null
+++ b/backend/src/main/kotlin/com/lightswitch/infrastructure/database/model/SdkType.kt
@@ -0,0 +1,17 @@
+package com.lightswitch.infrastructure.database.model
+
+enum class SdkType {
+    JAVA,
+    PYTHON,
+    ;
+
+    companion object {
+        fun from(type: String): SdkType {
+            return when (type.uppercase()) {
+                "JAVA" -> JAVA
+                "PYTHON" -> PYTHON
+                else -> throw IllegalArgumentException("Unsupported type: $type")
+            }
+        }
+    }
+}
diff --git a/backend/src/main/kotlin/com/lightswitch/presentation/controller/SdkController.kt b/backend/src/main/kotlin/com/lightswitch/presentation/controller/SdkController.kt
new file mode 100644
index 0000000..52ef00f
--- /dev/null
+++ b/backend/src/main/kotlin/com/lightswitch/presentation/controller/SdkController.kt
@@ -0,0 +1,67 @@
+package com.lightswitch.presentation.controller
+
+import com.lightswitch.infrastructure.database.model.SdkType
+import com.lightswitch.presentation.model.PayloadResponse
+import com.lightswitch.presentation.model.StatusResponse
+import com.lightswitch.presentation.model.sdk.CreateSdkKeyRequest
+import com.lightswitch.presentation.model.sdk.SdkKeyResponse
+import io.swagger.v3.oas.annotations.Operation
+import org.springframework.http.HttpStatus
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.RequestBody
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RequestParam
+import org.springframework.web.bind.annotation.ResponseStatus
+import org.springframework.web.bind.annotation.RestController
+
+@RestController
+@RequestMapping("/api/v1/sdks")
+class SdkController {
+    @Operation(
+        summary = "Create SDK key",
+    )
+    @PostMapping
+    @ResponseStatus(HttpStatus.CREATED)
+    fun createKey(
+        @RequestBody request: CreateSdkKeyRequest,
+    ): PayloadResponse<SdkKeyResponse> {
+        return PayloadResponse<SdkKeyResponse>(
+            status = "status",
+            message = "message",
+            data = null,
+        )
+    }
+
+    @Operation(
+        summary = "Get SDK key",
+    )
+    @GetMapping
+    fun getKey(
+        @RequestParam sdkType: String,
+    ): PayloadResponse<SdkKeyResponse> {
+        checkSdkType(sdkType)
+        return PayloadResponse<SdkKeyResponse>(
+            status = "status",
+            message = "message",
+            data = null,
+        )
+    }
+
+    @Operation(
+        summary = "Connect to SSE",
+    )
+    @GetMapping("/sse-connect")
+    fun connectSse(
+        @RequestParam sdkKey: String,
+    ): StatusResponse {
+        return StatusResponse(
+            status = "status",
+            message = "message",
+        )
+    }
+
+    fun checkSdkType(sdkType: String) {
+        SdkType.from(sdkType)
+    }
+}
diff --git a/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/CreateSdkKeyRequest.kt b/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/CreateSdkKeyRequest.kt
new file mode 100644
index 0000000..c21ba46
--- /dev/null
+++ b/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/CreateSdkKeyRequest.kt
@@ -0,0 +1,8 @@
+package com.lightswitch.presentation.model.sdk
+
+import jakarta.validation.constraints.Pattern
+
+data class CreateSdkKeyRequest(
+    @field:Pattern(regexp = "(?i)^(java|python)$", message = "Type must be one of: java, python")
+    val type: String,
+)
diff --git a/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/SdkKeyResponse.kt b/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/SdkKeyResponse.kt
new file mode 100644
index 0000000..fe8f240
--- /dev/null
+++ b/backend/src/main/kotlin/com/lightswitch/presentation/model/sdk/SdkKeyResponse.kt
@@ -0,0 +1,20 @@
+package com.lightswitch.presentation.model.sdk
+
+import com.lightswitch.infrastructure.database.entity.SdkClient
+import java.time.Instant
+
+class SdkKeyResponse(
+    val key: String,
+    val type: String,
+    val connectedAt: Instant,
+) {
+    companion object {
+        fun from(sdk: SdkClient): SdkKeyResponse {
+            return SdkKeyResponse(
+                key = sdk.sdkKey,
+                type = sdk.sdkType,
+                connectedAt = sdk.connectedAt,
+            )
+        }
+    }
+}