diff --git a/library/src/commonMain/kotlin/ink/literate/pawnote/api/assignment-upload-file.kt b/library/src/commonMain/kotlin/ink/literate/pawnote/api/assignment-upload-file.kt
new file mode 100644
index 0000000..9722b74
--- /dev/null
+++ b/library/src/commonMain/kotlin/ink/literate/pawnote/api/assignment-upload-file.kt
@@ -0,0 +1,55 @@
+package ink.literate.pawnote.api
+
+import ink.literate.pawnote.api.helpers.createEntityID
+import ink.literate.pawnote.core.RequestFN
+import ink.literate.pawnote.core.RequestUpload
+import ink.literate.pawnote.models.DocumentKind
+import ink.literate.pawnote.models.EntityState
+import ink.literate.pawnote.models.SessionHandle
+import ink.literate.pawnote.models.TabLocation
+import ink.literate.pawnote.models.errors.UploadSizeError
+import io.ktor.http.content.*
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.*
+import java.io.File
+import java.nio.channels.FileChannel
+
+suspend fun assignmentUploadFile (session: SessionHandle, assignmentID: String, file: File, fileName: String) {
+    // Check if the file can be uploaded.
+    // Otherwise we'll get an error during the upload.
+
+    val fileSize = file.length()
+    val maxFileSize = session.user.authorizations.maxAssignmentFileUploadSize
+
+    if (fileSize > maxFileSize)
+        throw UploadSizeError(maxFileSize)
+
+    // Ask to the server to store the file for us.
+    val fileUpload = RequestUpload(session, "SaisieTAFARendreEleve", file, fileName)
+    fileUpload.send()
+
+    val request = RequestFN(session.information, "SaisieTAFARendreEleve", Json.encodeToString(
+        buildJsonObject {
+            putJsonObject("_Signature_") {
+                put("onglet", TabLocation.Assignments.code)
+            }
+
+            putJsonObject("donnees") {
+                putJsonArray("listeFichiers") {
+                    addJsonObject {
+                        put("E", EntityState.CREATION.code)
+                        put("G", DocumentKind.FILE.code)
+                        put("L", fileName)
+                        put("N", createEntityID())
+                        put("idFichier", fileUpload.id)
+                        putJsonObject("TAF") {
+                            put("N", assignmentID)
+                        }
+                    }
+                }
+            }
+        }
+    ))
+
+    request.send()
+}
\ No newline at end of file
diff --git a/library/src/commonMain/kotlin/ink/literate/pawnote/api/helpers/entity-id.kt b/library/src/commonMain/kotlin/ink/literate/pawnote/api/helpers/entity-id.kt
new file mode 100644
index 0000000..2dd46c6
--- /dev/null
+++ b/library/src/commonMain/kotlin/ink/literate/pawnote/api/helpers/entity-id.kt
@@ -0,0 +1,12 @@
+package ink.literate.pawnote.api.helpers
+
+/**
+ * Defaults to `-1000`, used to generate IDs for newly created objects.
+ * Whenever an object is created using this ID, it should be decremented by `1`.
+ */
+var id = -1000
+
+fun createEntityID(): Int {
+    id -= 1
+    return id
+}
\ No newline at end of file
diff --git a/library/src/commonMain/kotlin/ink/literate/pawnote/core/request-upload.kt b/library/src/commonMain/kotlin/ink/literate/pawnote/core/request-upload.kt
new file mode 100644
index 0000000..e76372d
--- /dev/null
+++ b/library/src/commonMain/kotlin/ink/literate/pawnote/core/request-upload.kt
@@ -0,0 +1,75 @@
+package ink.literate.pawnote.core
+
+import ink.literate.pawnote.api.private.AES
+import ink.literate.pawnote.api.private.aesKeys
+import ink.literate.pawnote.models.SessionHandle
+import ink.literate.pawnote.models.errors.UploadFailedError
+import io.ktor.client.request.*
+import io.ktor.client.request.forms.*
+import io.ktor.http.*
+import io.ktor.http.content.*
+import io.ktor.util.*
+import io.ktor.utils.io.*
+import kotlinx.datetime.Clock
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.int
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonPrimitive
+import java.io.File
+import java.nio.file.Files
+
+@OptIn(InternalAPI::class)
+class RequestUpload(private val session: SessionHandle, functionName: String, file: File, private val fileName: String) {
+    val id = "selecfile_1_${Clock.System.now().toEpochMilliseconds()}"
+    var order: String = ""
+
+    private var url = ""
+    private var form: List<PartData>? = null
+
+
+    init {
+        session.information.order++
+
+        val keys = aesKeys(session.information)
+
+        order = AES.encrypt(session.information.order.toString().toByteArray(), keys.key, keys.iv)
+
+        val form = formData {
+            append("\"numeroOrdre\"", order)
+            append("\"numeroSession\"", session.information.id.toString())
+            append("\"nomRequete\"", functionName)
+            append("\"idFichier\"", id)
+            append("\"md5\"", "")
+            append("\"files[]\"", file.readBytes(), Headers.build {
+                append(HttpHeaders.ContentDisposition, "filename=\"${fileName}\"")
+                append(HttpHeaders.ContentType, Files.probeContentType(file.toPath()))
+            })
+        }
+
+        this.form = form
+        this.url = session.information.url + "/uploadfilesession/${session.information.accountKind.code}/${session.information.id}"
+    }
+
+    suspend fun send() {
+        var state = 3
+
+        val url = this.url
+
+        while (state == 3) {
+            val response = this.session.client.submitFormWithBinaryData(url = url,form!!) {
+                headers {
+                    append(HttpHeaders.ContentDisposition, "attachment; filename=\"${fileName}\"")
+                }
+            }
+
+            val json = Json.parseToJsonElement(response.content.readUTF8Line()!!)
+            state = json.jsonObject["etat"]!!.jsonPrimitive.int
+        }
+
+        // Even if there's an error, it bumped.
+        this.session.information.order++
+
+        if (state == 0 || state == 2)
+            throw UploadFailedError()
+    }
+}
\ No newline at end of file
diff --git a/library/src/commonMain/kotlin/ink/literate/pawnote/models/DocumentKind.kt b/library/src/commonMain/kotlin/ink/literate/pawnote/models/DocumentKind.kt
new file mode 100644
index 0000000..bc35e98
--- /dev/null
+++ b/library/src/commonMain/kotlin/ink/literate/pawnote/models/DocumentKind.kt
@@ -0,0 +1,9 @@
+package ink.literate.pawnote.models
+
+enum class DocumentKind (val code: Int) {
+    URL(0),
+    FILE(1),
+    CLOUD(2),
+    KIOSK_LINK(3),
+    CONFERENCE_LINK(4)
+}
\ No newline at end of file
diff --git a/library/src/commonMain/kotlin/ink/literate/pawnote/models/errors/upload.kt b/library/src/commonMain/kotlin/ink/literate/pawnote/models/errors/upload.kt
new file mode 100644
index 0000000..39b2e7e
--- /dev/null
+++ b/library/src/commonMain/kotlin/ink/literate/pawnote/models/errors/upload.kt
@@ -0,0 +1,5 @@
+package ink.literate.pawnote.models.errors
+
+class UploadSizeError (maxSizeInBytes: Double) : Error("The file you are trying to upload is too large, maximum allowed is $maxSizeInBytes bytes")
+
+class UploadFailedError : Error("The file upload failed")
\ No newline at end of file