diff --git a/src/pl/desuonline/AndroidManifest.xml b/src/pl/desuonline/AndroidManifest.xml
new file mode 100644
index 000000000..0978de1ae
--- /dev/null
+++ b/src/pl/desuonline/AndroidManifest.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="eu.kanade.tachiyomi.animeextension">
+</manifest>
diff --git a/src/pl/desuonline/build.gradle b/src/pl/desuonline/build.gradle
new file mode 100644
index 000000000..21169db53
--- /dev/null
+++ b/src/pl/desuonline/build.gradle
@@ -0,0 +1,12 @@
+apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+
+ext {
+    extName = 'desu-online'
+    pkgNameSuffix = 'pl.desuonline'
+    extClass = '.DesuOnline'
+    extVersionCode = 1
+    libVersion = '13'
+}
+
+apply from: "$rootDir/common.gradle"
diff --git a/src/pl/desuonline/res/mipmap-hdpi/ic_launcher.png b/src/pl/desuonline/res/mipmap-hdpi/ic_launcher.png
new file mode 100644
index 000000000..53298291e
Binary files /dev/null and b/src/pl/desuonline/res/mipmap-hdpi/ic_launcher.png differ
diff --git a/src/pl/desuonline/res/mipmap-mdpi/ic_launcher.png b/src/pl/desuonline/res/mipmap-mdpi/ic_launcher.png
new file mode 100644
index 000000000..38c510159
Binary files /dev/null and b/src/pl/desuonline/res/mipmap-mdpi/ic_launcher.png differ
diff --git a/src/pl/desuonline/res/mipmap-xhdpi/ic_launcher.png b/src/pl/desuonline/res/mipmap-xhdpi/ic_launcher.png
new file mode 100644
index 000000000..5e9ffea12
Binary files /dev/null and b/src/pl/desuonline/res/mipmap-xhdpi/ic_launcher.png differ
diff --git a/src/pl/desuonline/res/mipmap-xxhdpi/ic_launcher.png b/src/pl/desuonline/res/mipmap-xxhdpi/ic_launcher.png
new file mode 100644
index 000000000..987160c05
Binary files /dev/null and b/src/pl/desuonline/res/mipmap-xxhdpi/ic_launcher.png differ
diff --git a/src/pl/desuonline/res/mipmap-xxxhdpi/ic_launcher.png b/src/pl/desuonline/res/mipmap-xxxhdpi/ic_launcher.png
new file mode 100644
index 000000000..f3a06cc82
Binary files /dev/null and b/src/pl/desuonline/res/mipmap-xxxhdpi/ic_launcher.png differ
diff --git a/src/pl/desuonline/res/web_hi_res_512.png b/src/pl/desuonline/res/web_hi_res_512.png
new file mode 100644
index 000000000..641868dd6
Binary files /dev/null and b/src/pl/desuonline/res/web_hi_res_512.png differ
diff --git a/src/pl/desuonline/src/eu/kanade/tachiyomi/animeextension/pl/desuonline/DesuOnline.kt b/src/pl/desuonline/src/eu/kanade/tachiyomi/animeextension/pl/desuonline/DesuOnline.kt
new file mode 100644
index 000000000..b52c3eda6
--- /dev/null
+++ b/src/pl/desuonline/src/eu/kanade/tachiyomi/animeextension/pl/desuonline/DesuOnline.kt
@@ -0,0 +1,238 @@
+package eu.kanade.tachiyomi.animeextension.pl.desuonline
+
+import android.app.Application
+import android.content.SharedPreferences
+import android.util.Base64
+import androidx.preference.ListPreference
+import androidx.preference.PreferenceScreen
+import eu.kanade.tachiyomi.animesource.ConfigurableAnimeSource
+import eu.kanade.tachiyomi.animesource.model.AnimeFilterList
+import eu.kanade.tachiyomi.animesource.model.SAnime
+import eu.kanade.tachiyomi.animesource.model.SEpisode
+import eu.kanade.tachiyomi.animesource.model.Video
+import eu.kanade.tachiyomi.animesource.online.ParsedAnimeHttpSource
+import eu.kanade.tachiyomi.network.GET
+import eu.kanade.tachiyomi.network.POST
+import eu.kanade.tachiyomi.util.asJsoup
+import kotlinx.serialization.decodeFromString
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.jsonObject
+import kotlinx.serialization.json.jsonPrimitive
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import okhttp3.MediaType.Companion.toMediaType
+import okhttp3.RequestBody
+import okhttp3.RequestBody.Companion.toRequestBody
+import okhttp3.Response
+import org.jsoup.nodes.Document
+import org.jsoup.nodes.Element
+import uy.kohesive.injekt.Injekt
+import uy.kohesive.injekt.api.get
+import java.text.SimpleDateFormat
+import java.util.Locale
+
+class DesuOnline : ConfigurableAnimeSource, ParsedAnimeHttpSource() {
+
+    override val name = "desu-online"
+
+    override val baseUrl = "https://desu-online.pl"
+
+    override val lang = "pl"
+
+    override val supportsLatest = true
+
+    override val client = network.cloudflareClient
+
+    private val json = Json {
+        ignoreUnknownKeys = true
+    }
+
+    private val preferences: SharedPreferences by lazy {
+        Injekt.get<Application>().getSharedPreferences("source_$id", 0x0000)
+    }
+
+    // ============================== Popular ===============================
+
+    override fun popularAnimeRequest(page: Int) = GET("$baseUrl/anime/?page=$page&order=popular")
+
+    override fun popularAnimeSelector() = "div.listupd div.bsx > a"
+
+    override fun popularAnimeNextPageSelector() = "div.pagination > a.next, div.hpage > a.r"
+
+    override fun popularAnimeFromElement(element: Element): SAnime {
+        val animeTitle = element.select("div.tt > h2").text().trim()
+        val img = element.select("div.limit > img")
+        return SAnime.create().apply {
+            setUrlWithoutDomain(element.attr("href"))
+            title = animeTitle
+            thumbnail_url = img.attr("data-src")
+        }
+    }
+
+    // =========================== Anime Details ============================
+
+    override fun animeDetailsParse(document: Document): SAnime {
+        val img = document.select("div.thumb > img").ifEmpty { null }
+        val studio = document.select("div.info-content > div.spe > span:contains(Studio:)").ifEmpty { null }
+        val statusSpan = document.select("div.info-content > div.spe > span:contains(Status:)").ifEmpty { null }
+        val desc = document.select("div[itemprop=description] > p:last-child").ifEmpty { null }
+        val director = document.select("div.info-content > div.spe > span:contains(Reżyser:)").ifEmpty { null }
+        val genres = document.select("div.genxed > a")
+        return SAnime.create().apply {
+            title = document.select("h1.entry-title").text()
+            thumbnail_url = img?.attr("data-src")
+            author = studio?.text()?.substringAfter("Studio: ")
+            status = parseStatus(statusSpan?.text()?.substringAfter("Status: "))
+            description = desc?.text()?.trim()
+            artist = director?.text()?.substringAfter("Reżyser: ")
+            genre = genres.joinToString { it.text() }
+        }
+    }
+
+    // ============================== Episodes ==============================
+
+    override fun episodeListSelector() = "div.eplister > ul > li"
+
+    override fun episodeFromElement(element: Element): SEpisode {
+        val a = element.select("a")
+        val epNum = a.select("div.epl-num").text()
+        val epTitle = a.select("div.epl-title").text()
+        val date = a.select("div.epl-date").text()
+        return SEpisode.create().apply {
+            setUrlWithoutDomain(a.attr("href"))
+            name = "Odcinek $epNum: $epTitle"
+            date_upload = parseDate(date)
+            episode_number = epNum.substringBefore(" ").toFloatOrNull() ?: 0F
+        }
+    }
+
+    // ============================ Video Links =============================
+
+    override fun videoListParse(response: Response): List<Video> {
+        val videoList = mutableListOf<Video>()
+        val document = response.asJsoup()
+        document.select("select.mirror > option").filter {
+            it.text().contains("CDA")
+        }.map {
+            val mirror = it.text().trim()
+
+            val iframe = String(Base64.decode(it.attr("value"), Base64.DEFAULT))
+            val src = iframe.substringAfter("src=\"").substringBefore("\"")
+
+            val videoId = src.toHttpUrl().encodedPathSegments.last()
+
+            val playerDataHtml = client.newCall(GET(src)).execute()
+                .asJsoup().select("div[id=mediaplayer$videoId]")
+                .attr("player_data")
+            val playerData = json.decodeFromString<JsonObject>(playerDataHtml)
+
+            val timeStamp = playerData["api"]!!.jsonObject["ts"]!!.jsonPrimitive.content
+                .substringBefore("_")
+            val videoData = playerData["video"]!!.jsonObject
+            val hash = videoData["hash2"]!!.jsonPrimitive.content
+
+            val qualities = videoData["qualities"]!!.jsonObject
+
+            qualities.keys.reversed().map { quality ->
+                val qualityId = qualities[quality]!!.jsonPrimitive.content
+                val body = cdaBody(videoId, qualityId, timeStamp, hash)
+                val videoResponse = json.decodeFromString<JsonObject>(
+                    client.newCall(POST("https://www.cda.pl/", body = body))
+                        .execute().body!!.string()
+                )
+                val videoUrl = videoResponse["result"]!!.jsonObject["resp"]!!.jsonPrimitive.content
+                videoList.add(Video(videoUrl, "$mirror: $quality", videoUrl))
+            }
+        }
+        return videoList
+    }
+
+    override fun videoFromElement(element: Element): Video = throw Exception("not used")
+    override fun videoListSelector(): String = throw Exception("not used")
+    override fun videoUrlParse(document: Document): String = throw Exception("not used")
+
+    // =============================== Search ===============================
+
+    override fun searchAnimeRequest(page: Int, query: String, filters: AnimeFilterList) =
+        GET("$baseUrl/anime/?page=$page&s=$query")
+
+    override fun searchAnimeSelector() = popularAnimeSelector()
+    override fun searchAnimeNextPageSelector() = popularAnimeNextPageSelector()
+    override fun searchAnimeFromElement(element: Element) = popularAnimeFromElement(element)
+
+    // =============================== Latest ===============================
+
+    override fun latestUpdatesRequest(page: Int) = GET("$baseUrl/anime/?page=$page&order=latest")
+
+    override fun latestUpdatesSelector() = popularAnimeSelector()
+    override fun latestUpdatesNextPageSelector() = popularAnimeNextPageSelector()
+    override fun latestUpdatesFromElement(element: Element) = popularAnimeFromElement(element)
+
+    // =============================== Preferences ===============================
+
+    override fun setupPreferenceScreen(screen: PreferenceScreen) {
+        val videoQualityPref = ListPreference(screen.context).apply {
+            key = "preferred_quality"
+            title = "Preferred quality"
+            entries = arrayOf("1080p", "720p", "480p", "360p")
+            entryValues = arrayOf("1080", "720", "480", "360")
+            setDefaultValue("1080")
+            summary = "%s"
+
+            setOnPreferenceChangeListener { _, newValue ->
+                val selected = newValue as String
+                val index = findIndexOfValue(selected)
+                val entry = entryValues[index] as String
+                preferences.edit().putString(key, entry).commit()
+            }
+        }
+        screen.addPreference(videoQualityPref)
+    }
+
+    override fun List<Video>.sort(): List<Video> {
+        val quality = preferences.getString("preferred_quality", "1080")
+        if (quality != null) {
+            val newList = mutableListOf<Video>()
+            var preferred = 0
+            for (video in this) {
+                if (video.quality.contains(quality)) {
+                    newList.add(preferred, video)
+                    preferred++
+                } else {
+                    newList.add(video)
+                }
+            }
+            return newList
+        }
+        return this
+    }
+
+    // ============================= Utilities ==============================
+
+    private fun parseStatus(statusString: String?): Int {
+        return when (statusString?.trim()) {
+            "Zakończony" -> SAnime.COMPLETED
+            "Emitowany" -> SAnime.ONGOING
+            else -> SAnime.UNKNOWN
+        }
+    }
+
+    private fun parseDate(dateStr: String): Long {
+        return runCatching { DATE_FORMATTER.parse(dateStr)?.time }
+            .getOrNull() ?: 0L
+    }
+
+    private fun cdaBody(
+        videoId: String,
+        qualityId: String,
+        timeStamp: String,
+        hash: String,
+    ): RequestBody {
+        return "{\"jsonrpc\":\"2.0\",\"method\":\"videoGetLink\",\"params\":[\"$videoId\",\"$qualityId\",$timeStamp,\"$hash\",{}],\"id\":4}"
+            .toRequestBody("application/json".toMediaType())
+    }
+}
+
+private val DATE_FORMATTER by lazy {
+    SimpleDateFormat("d MMM, yyyy", Locale("pl"))
+}