diff --git a/source/core/audio/jail_audio.hpp b/source/core/audio/jail_audio.hpp
index 509b4c6..57858b4 100644
--- a/source/core/audio/jail_audio.hpp
+++ b/source/core/audio/jail_audio.hpp
@@ -260,7 +260,7 @@ inline void JA_Update() {
 
 inline void JA_Init(const int freq, const SDL_AudioFormat format, const int num_channels) {
     JA_audioSpec = {.format = format, .channels = num_channels, .freq = freq};
-    if (sdlAudioDevice != 0u) {
+    if (sdlAudioDevice != 0U) {
         SDL_CloseAudioDevice(sdlAudioDevice);
     }
     sdlAudioDevice = SDL_OpenAudioDevice(SDL_AUDIO_DEVICE_DEFAULT_PLAYBACK, &JA_audioSpec);
@@ -280,7 +280,7 @@ inline void JA_Quit() {
         SDL_DestroyAudioStream(outgoing_music.stream);
         outgoing_music.stream = nullptr;
     }
-    if (sdlAudioDevice != 0u) {
+    if (sdlAudioDevice != 0U) {
         SDL_CloseAudioDevice(sdlAudioDevice);
     }
     sdlAudioDevice = 0;
@@ -586,7 +586,7 @@ inline void JA_EnableMusic(const bool value) {
 inline auto JA_LoadSound(uint8_t* buffer, uint32_t size) -> JA_Sound_t* {
     auto sound = std::make_unique<JA_Sound_t>();
     Uint8* raw = nullptr;
-    if (!SDL_LoadWAV_IO(SDL_IOFromMem(buffer, size), 1, &sound->spec, &raw, &sound->length)) {
+    if (!SDL_LoadWAV_IO(SDL_IOFromMem(buffer, size), true, &sound->spec, &raw, &sound->length)) {
         std::cout << "Failed to load WAV from memory: " << SDL_GetError() << '\n';
         return nullptr;
     }
diff --git a/source/core/jail/jdraw8.cpp b/source/core/jail/jdraw8.cpp
index 905a014..cd7d70f 100644
--- a/source/core/jail/jdraw8.cpp
+++ b/source/core/jail/jdraw8.cpp
@@ -87,7 +87,7 @@ auto JD8_LoadPalette(const char* file) -> JD8_Palette {
     // Sempre retorna un buffer de 256 colors reservat amb `new Color[256]`
     // — el caller és responsable d'alliberar-lo amb `delete[]` (o lliurar-ne
     // l'ownership a `JD8_SetScreenPalette`).
-    auto palette = new Color[256];
+    auto* palette = new Color[256];
 
     if (Resource::Cache::get() != nullptr) {
         try {
@@ -167,7 +167,7 @@ void JD8_BlitToSurface(int x, int y, JD8_Surface surface, int sx, int sy, int sw
     }
 }
 
-void JD8_BlitCK(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, Uint8 colorkey) {
+void JD8_BlitCK(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, Uint8 colorkey) {
     int src_pointer = sx + (sy * 320);
     int dst_pointer = x + (y * 320);
     for (int j = 0; j < sh; j++) {
@@ -181,7 +181,7 @@ void JD8_BlitCK(int x, int y, const JD8_Surface surface, int sx, int sy, int sw,
     }
 }
 
-void JD8_BlitCKCut(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, Uint8 colorkey) {
+void JD8_BlitCKCut(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, Uint8 colorkey) {
     int src_pointer = sx + (sy * 320);
     int dst_pointer = x + (y * 320);
     for (int j = 0; j < sh; j++) {
@@ -195,7 +195,7 @@ void JD8_BlitCKCut(int x, int y, const JD8_Surface surface, int sx, int sy, int
     }
 }
 
-void JD8_BlitCKScroll(int y, const JD8_Surface surface, int sx, int sy, int sh, Uint8 colorkey) {
+void JD8_BlitCKScroll(int y, const Uint8* surface, int sx, int sy, int sh, Uint8 colorkey) {
     int dst_pointer = y * 320;
     for (int j = sy; j < sy + sh; j++) {
         for (int i = 0; i < 320; i++) {
@@ -208,7 +208,7 @@ void JD8_BlitCKScroll(int y, const JD8_Surface surface, int sx, int sy, int sh,
     }
 }
 
-void JD8_BlitCKToSurface(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, JD8_Surface dest, Uint8 colorkey) {
+void JD8_BlitCKToSurface(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, JD8_Surface dest, Uint8 colorkey) {
     int src_pointer = sx + (sy * 320);
     int dst_pointer = x + (y * 320);
     for (int j = 0; j < sh; j++) {
@@ -239,11 +239,11 @@ auto JD8_GetFramebuffer() -> Uint32* {
     return pixel_data;
 }
 
-void JD8_FreeSurface(const JD8_Surface surface) {
+void JD8_FreeSurface(JD8_Surface surface) {  // NOLINT(readability-non-const-parameter): allibera memòria, no pot ser const
     delete[] surface;
 }
 
-auto JD8_GetPixel(JD8_Surface surface, int x, int y) -> Uint8 {
+auto JD8_GetPixel(const Uint8* surface, int x, int y) -> Uint8 {
     return surface[x + (y * 320)];
 }
 
diff --git a/source/core/jail/jdraw8.hpp b/source/core/jail/jdraw8.hpp
index e379a1e..ccfe647 100644
--- a/source/core/jail/jdraw8.hpp
+++ b/source/core/jail/jdraw8.hpp
@@ -36,13 +36,13 @@ void JD8_Blit(int x, int y, JD8_Surface surface, int sx, int sy, int sw, int sh)
 
 void JD8_BlitToSurface(int x, int y, JD8_Surface surface, int sx, int sy, int sw, int sh, JD8_Surface dest);
 
-void JD8_BlitCK(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, Uint8 colorkey);
+void JD8_BlitCK(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, Uint8 colorkey);
 
-void JD8_BlitCKCut(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, Uint8 colorkey);
+void JD8_BlitCKCut(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, Uint8 colorkey);
 
-void JD8_BlitCKScroll(int y, const JD8_Surface surface, int sx, int sy, int sh, Uint8 colorkey);
+void JD8_BlitCKScroll(int y, const Uint8* surface, int sx, int sy, int sh, Uint8 colorkey);
 
-void JD8_BlitCKToSurface(int x, int y, const JD8_Surface surface, int sx, int sy, int sw, int sh, JD8_Surface dest, Uint8 colorkey);
+void JD8_BlitCKToSurface(int x, int y, const Uint8* surface, int sx, int sy, int sw, int sh, JD8_Surface dest, Uint8 colorkey);
 
 // Converteix la pantalla indexada a ARGB. El Director crida aquesta
 // funció al final de cada tick i després llegeix el framebuffer via
@@ -53,9 +53,9 @@ void JD8_Flip();
 // JD8_Flip(). Propietat de jdraw8 — el caller no ha de lliberar-lo.
 auto JD8_GetFramebuffer() -> Uint32*;
 
-void JD8_FreeSurface(const JD8_Surface surface);
+void JD8_FreeSurface(JD8_Surface surface);
 
-auto JD8_GetPixel(JD8_Surface surface, int x, int y) -> Uint8;
+auto JD8_GetPixel(const Uint8* surface, int x, int y) -> Uint8;
 
 void JD8_PutPixel(JD8_Surface surface, int x, int y, Uint8 pixel);
 
diff --git a/source/core/jail/jinput.cpp b/source/core/jail/jinput.cpp
index beaec68..a30cc11 100644
--- a/source/core/jail/jinput.cpp
+++ b/source/core/jail/jinput.cpp
@@ -81,7 +81,7 @@ void JI_Update() {
 
     if (wait_ms > 0.0F) {
         wait_ms -= delta_ms;
-        wait_ms = std::max(wait_ms, 0.0f);
+        wait_ms = std::max(wait_ms, 0.0F);
     }
 
     // Consumim el flag de "alguna tecla no-GUI polsada" del director
diff --git a/source/core/rendering/menu.cpp b/source/core/rendering/menu.cpp
index 482740d..0da7b74 100644
--- a/source/core/rendering/menu.cpp
+++ b/source/core/rendering/menu.cpp
@@ -228,7 +228,7 @@ namespace Menu {
         pct = std::min(pct, 100);
         char buf[8];
         std::snprintf(buf, sizeof(buf), "%d%%", pct);
-        return std::string(buf);
+        return {buf};
     }
 
     // Canvi +/- d'un volum en steps de 0.05 (5%) amb clamping
diff --git a/source/core/rendering/overlay.cpp b/source/core/rendering/overlay.cpp
index 04fd6ab..a884042 100644
--- a/source/core/rendering/overlay.cpp
+++ b/source/core/rendering/overlay.cpp
@@ -418,7 +418,7 @@ namespace Overlay {
     void setRenderInfoSegments(const char* s0, const char* s1, const char* s2, const char* s3, unsigned int mono_mask) {
         const char* segs[INFO_SEGMENT_COUNT] = {s0, s1, s2, s3};
         for (int i = 0; i < INFO_SEGMENT_COUNT; i++) {
-            info_segments_[i].mono_digits = (((mono_mask >> i) & 1U) != 0u);
+            info_segments_[i].mono_digits = (((mono_mask >> i) & 1U) != 0U);
             if (segs[i] != nullptr && *segs[i] != '\0') {
                 info_segments_[i].text = segs[i];
                 info_segments_[i].visible = true;
diff --git a/source/core/system/director.hpp b/source/core/system/director.hpp
index 94ef26f..5f8a1e2 100644
--- a/source/core/system/director.hpp
+++ b/source/core/system/director.hpp
@@ -66,7 +66,7 @@ class Director {
     static void initGameContext();
     // Construeix l'escena apropiada segons game_state_ i info::ctx.
     // Retorna nullptr si l'state actual no té escena registrada (bug).
-    auto createNextScene() const -> std::unique_ptr<scenes::Scene>;
+    [[nodiscard]] auto createNextScene() const -> std::unique_ptr<scenes::Scene>;
 
     // Buffers persistents entre iteracions. Abans eren locals a run(),
     // ara són membres perquè iterate() els pot reutilitzar sense tornar-los
diff --git a/source/game/mapa.cpp b/source/game/mapa.cpp
index 85b59a4..0c8a73b 100644
--- a/source/game/mapa.cpp
+++ b/source/game/mapa.cpp
@@ -40,6 +40,8 @@ void Mapa::draw() {
             case 3:  // Left
                 JD8_BlitCKToSurface(sam->x + 8, sam->y, this->gfx, 45 + (14 - sam->frame_pejades), 125, 1, 15, this->fondo, 255);
                 break;
+            default:
+                break;
         }
     }
 
@@ -124,6 +126,8 @@ void Mapa::preparaFondoEstatic() {
                 case 6:
                     JD8_BlitToSurface(20 + (x * 15), 30 + (y * 15), this->gfx, 145, 80, 15, 15, this->fondo);
                     break;
+                default:
+                    break;
             }
         }
     }
@@ -284,6 +288,8 @@ void Mapa::comprovaCaixa(Uint8 num) {
                 this->farao = this->clau = true;
             }
             break;
+        default:
+            break;
     }
 
     this->comprovaPorta();
diff --git a/source/game/marcador.cpp b/source/game/marcador.cpp
index 33c6a4e..8b7936c 100644
--- a/source/game/marcador.cpp
+++ b/source/game/marcador.cpp
@@ -59,5 +59,7 @@ void Marcador::pintaNumero(Uint16 x, Uint16 y, Uint8 num) {
         case 9:
             JD8_BlitCK(x, y, this->gfx, 131, 193, 10, 7, 255);
             break;
+        default:
+            break;
     }
 }
diff --git a/source/game/momia.cpp b/source/game/momia.cpp
index c2b9860..a7e0396 100644
--- a/source/game/momia.cpp
+++ b/source/game/momia.cpp
@@ -143,6 +143,8 @@ auto Momia::update() -> bool {
                     this->x--;
                 }
                 break;
+            default:
+                break;
         }
 
         if (JG_GetCycleCounter() % this->cycles_per_frame == 0) {
diff --git a/source/game/prota.cpp b/source/game/prota.cpp
index 8a2d915..38a942c 100644
--- a/source/game/prota.cpp
+++ b/source/game/prota.cpp
@@ -150,6 +150,8 @@ auto Prota::update() -> Uint8 {
                     this->x--;
                 }
                 break;
+            default:
+                break;
         }
 
         if (dir == 4) {
@@ -166,7 +168,7 @@ auto Prota::update() -> Uint8 {
                 }
             }
         }
-        eixir = 0u;
+        eixir = 0U;
     } else {
         if (JG_GetCycleCounter() % this->cycles_per_frame == 0) {
             this->cur_frame++;
diff --git a/source/game/scenes/credits_scene.cpp b/source/game/scenes/credits_scene.cpp
index 73f18ec..83a460b 100644
--- a/source/game/scenes/credits_scene.cpp
+++ b/source/game/scenes/credits_scene.cpp
@@ -36,9 +36,8 @@ namespace {
 
 namespace scenes {
 
-    CreditsScene::~CreditsScene() {
-        // No toquem la paleta activa: SetScreenPalette n'ha pres ownership.
-    }
+    // No toquem la paleta activa: SetScreenPalette n'ha pres ownership.
+    CreditsScene::~CreditsScene() = default;
 
     void CreditsScene::onEnter() {
         // El vell doCredits no tocava música — heretava la del doSlides
diff --git a/source/game/scenes/intro_new_logo_scene.cpp b/source/game/scenes/intro_new_logo_scene.cpp
index 320b6e3..8853695 100644
--- a/source/game/scenes/intro_new_logo_scene.cpp
+++ b/source/game/scenes/intro_new_logo_scene.cpp
@@ -41,11 +41,10 @@ namespace scenes {
 
     IntroNewLogoScene::IntroNewLogoScene() = default;
 
-    IntroNewLogoScene::~IntroNewLogoScene() {
-        // No alliberem `pal_`: JD8_SetScreenPalette n'ha pres ownership i
-        // el proper SetScreenPalette / FadeToPal el lliurarà. Alliberar-lo
-        // ací provocaria double free.
-    }
+    // No alliberem `pal_`: JD8_SetScreenPalette n'ha pres ownership i el
+    // proper SetScreenPalette / FadeToPal el lliurarà. Alliberar-lo ací
+    // provocaria double free.
+    IntroNewLogoScene::~IntroNewLogoScene() = default;
 
     void IntroNewLogoScene::onEnter() {
         playMusic("music/menu.ogg");
diff --git a/source/game/scenes/intro_scene.cpp b/source/game/scenes/intro_scene.cpp
index e66fd3a..425c467 100644
--- a/source/game/scenes/intro_scene.cpp
+++ b/source/game/scenes/intro_scene.cpp
@@ -59,11 +59,10 @@ namespace scenes {
 
     IntroScene::IntroScene() = default;
 
-    IntroScene::~IntroScene() {
-        // No alliberem `pal_`: JD8_SetScreenPalette n'ha pres ownership i el
-        // proper SetScreenPalette / FadeToPal la lliurarà. Alliberar-la ací
-        // provocaria double free.
-    }
+    // No alliberem `pal_`: JD8_SetScreenPalette n'ha pres ownership i el
+    // proper SetScreenPalette / FadeToPal la lliurarà. Alliberar-la ací
+    // provocaria double free.
+    IntroScene::~IntroScene() = default;
 
     void IntroScene::onEnter() {
         playMusic("music/menu.ogg");
diff --git a/source/game/scenes/intro_sprites_scene.cpp b/source/game/scenes/intro_sprites_scene.cpp
index 92ce657..682e474 100644
--- a/source/game/scenes/intro_sprites_scene.cpp
+++ b/source/game/scenes/intro_sprites_scene.cpp
@@ -286,8 +286,9 @@ namespace {
                 return variant_1;
             case 2:
                 return variant_2;
+            default:
+                return variant_0;
         }
-        return variant_0;
     }
 
     auto variant_length(int variant) -> int {
@@ -298,8 +299,9 @@ namespace {
                 return sizeof(variant_1) / sizeof(variant_1[0]);
             case 2:
                 return sizeof(variant_2) / sizeof(variant_2[0]);
+            default:
+                return 0;
         }
-        return 0;
     }
 
     auto phase_step_count(const SpritePhase& p) -> int {