chore(core): adjust hardcoded paths to use xtask build

diff --git a/core/emu.py b/core/emu.py
index a754bdc6..5e512600 100755
--- a/core/emu.py
+++ b/core/emu.py
@@ -24,7 +24,7 @@ except Exception:
 
 
 HERE = Path(__file__).resolve().parent
-MICROPYTHON = HERE / "build" / "unix" / "trezor-emu-core"
+MICROPYTHON = HERE / "build-xtask" / "artifacts" / "latest" / "firmware-emu"
 SRC_DIR = HERE / "src"
 
 PROFILE_BASE = Path.home() / ".trezoremu"
diff --git a/core/tests/run_tests.sh b/core/tests/run_tests.sh
index de858fce..21df685c 100755
--- a/core/tests/run_tests.sh
+++ b/core/tests/run_tests.sh
@@ -3,7 +3,7 @@
 declare -a results
 declare -i passed=0 failed=0 exit_code=0
 declare COLOR_GREEN='\e[32m' COLOR_RED='\e[91m' COLOR_RESET='\e[39m'
-MICROPYTHON="${MICROPYTHON:-../build/unix/trezor-emu-core -X heapsize=2M}"
+declare MICROPYTHON="${MICROPYTHON:-../build-xtask/artifacts/latest/firmware-emu -X heapsize=2M}"
 export SDL_VIDEODRIVER=dummy
 
 print_summary() {
diff --git a/core/tools/coverage-collect.py b/core/tools/coverage-collect.py
index 56370578..850edf89 100755
--- a/core/tools/coverage-collect.py
+++ b/core/tools/coverage-collect.py
@@ -12,8 +12,8 @@ data = coverage.CoverageData(result_filename)
 
 
 def to_preprocessed_path(py_path: Path) -> Path:
-    # Remap <prefix>/src/<rel>.py → <prefix>/build/unix/src/<rel>.i so coverage
-    # reports against the preprocessed source actually compiled into the frozen
+    # Remap <prefix>/src/<rel>.py → <prefix>/build-xtask/artifacts/latest/mpy-files/<rel>.i
+    # so coverage reports against the preprocessed source actually compiled into the frozen
     # build (dead feature-flag branches already rewritten to `if False:`).
     # Fall back to the original .py path when no .i exists (e.g. unfrozen
     # debug-only modules loaded directly from src/).
@@ -23,7 +23,11 @@ def to_preprocessed_path(py_path: Path) -> Path:
     src_index = path_parts.index("src")
     prefix = path_parts[:src_index]
     rest = path_parts[src_index + 1 :]
-    i_path = Path(*prefix) / "build/unix/src" / Path(*rest).with_suffix(".i")
+    i_path = (
+        Path(*prefix)
+        / "build-xtask/artifacts/latest/mpy-files"
+        / Path(*rest).with_suffix(".i")
+    )
     return i_path if os.path.exists(i_path) else py_path
 
 
diff --git a/tests/emulators.py b/tests/emulators.py
index c309bebe..b604d8eb 100644
--- a/tests/emulators.py
+++ b/tests/emulators.py
@@ -35,7 +35,7 @@ BINDIR = ROOT / "tests" / "emulators"
 _SHARED_TROPIC_MODELS: Dict[str, TropicModel] = {}
 
 LOCAL_BUILD_PATHS = {
-    "core": ROOT / "core" / "build" / "unix" / "trezor-emu-core",
+    "core": ROOT / "core" / "build-xtask" / "artifacts" / "latest" / "firmware-emu",
     "legacy": ROOT / "legacy" / "firmware" / "trezor.elf",
 }
 
diff --git a/tools/print-rust-stack-sizes.py b/tools/print-rust-stack-sizes.py
index 35f6eef0..cdd99008 100755
--- a/tools/print-rust-stack-sizes.py
+++ b/tools/print-rust-stack-sizes.py
@@ -13,7 +13,7 @@ SYMBOL_TYPES = ("t", "w")  # text, weak
 
 ROOT = Path(__file__).parent.parent.resolve()
 
-FIRMWARE_ELF = ROOT / "core" / "build" / "firmware" / "firmware.elf"
+FIRMWARE_ELF = ROOT / "core" / "build-xtask" / "artifacts" / "latest" / "firmware.elf"
 elf = ELFFile(FIRMWARE_ELF.open("rb"))