diff --git a/build/pkgs/eclib/checksums.ini b/build/pkgs/eclib/checksums.ini
index ff0ea83451a..14061199f9f 100644
--- a/build/pkgs/eclib/checksums.ini
+++ b/build/pkgs/eclib/checksums.ini
@@ -1,4 +1,4 @@
 tarball=eclib-VERSION.tar.bz2
-sha1=ec8dd87df46ac5a54b548354681085d1da6e7e13
-sha256=9f8c2b32e24a4f20d7cc2d336ea30c8ea03b5b0953c2d32adda0c496e7616899
+sha1=5593348fef3ee35918815fbc6444c3003bdb4fa4
+sha256=b88d4b52612e491c5415946d9e35f2062ca1015ee7fbbe0b61f158fa74cb4bc9
 upstream_url=https://github.com/JohnCremona/eclib/releases/download/VERSION/eclib-VERSION.tar.bz2
diff --git a/build/pkgs/eclib/package-version.txt b/build/pkgs/eclib/package-version.txt
index b0aec664e8d..b128998250b 100644
--- a/build/pkgs/eclib/package-version.txt
+++ b/build/pkgs/eclib/package-version.txt
@@ -1 +1 @@
-20250122
+20250627
diff --git a/build/pkgs/eclib/spkg-configure.m4 b/build/pkgs/eclib/spkg-configure.m4
index 23771dad1bd..ea1e28a8823 100644
--- a/build/pkgs/eclib/spkg-configure.m4
+++ b/build/pkgs/eclib/spkg-configure.m4
@@ -1,7 +1,7 @@
 SAGE_SPKG_CONFIGURE([eclib], [
   SAGE_SPKG_DEPCHECK([ntl pari flint], [
     dnl use existing eclib only if the version reported by pkg-config is recent enough
-    m4_pushdef([SAGE_ECLIB_VER],["20241112"])
+    m4_pushdef([SAGE_ECLIB_VER],["20250627"])
     PKG_CHECK_MODULES([ECLIB], [eclib >= SAGE_ECLIB_VER], [
       AC_CACHE_CHECK([for mwrank version == SAGE_ECLIB_VER], [ac_cv_path_MWRANK], [
         AC_PATH_PROGS_FEATURE_CHECK([MWRANK], [mwrank], [
diff --git a/build/pkgs/flint/checksums.ini b/build/pkgs/flint/checksums.ini
index b7ccee17ce3..53a1842d271 100644
--- a/build/pkgs/flint/checksums.ini
+++ b/build/pkgs/flint/checksums.ini
@@ -1,4 +1,4 @@
 tarball=flint-VERSION.tar.gz
-sha1=ebca3a55e48373c2eeee6c172051f3177845e121
-sha256=577d7729e4c2e79ca1e894ad2ce34bc73516a92f623d42562694817f888a17eb
+sha1=dae6d32b25e46a6ab92514b4dfa64b06fdf247ec
+sha256=64d70e513076cfa971e0410b58c1da5d35112913e9a56b44e2c681b459d3eafb
 upstream_url=https://github.com/flintlib/flint/releases/download/vVERSION/flint-VERSION.tar.gz
diff --git a/build/pkgs/flint/package-version.txt b/build/pkgs/flint/package-version.txt
index be94e6f53db..bea438e9ade 100644
--- a/build/pkgs/flint/package-version.txt
+++ b/build/pkgs/flint/package-version.txt
@@ -1 +1 @@
-3.2.2
+3.3.1
diff --git a/build/pkgs/flint/spkg-build.in b/build/pkgs/flint/spkg-build.in
index ffb822c8a97..30f370e2d10 100644
--- a/build/pkgs/flint/spkg-build.in
+++ b/build/pkgs/flint/spkg-build.in
@@ -1,3 +1,7 @@
 cd src
+
+# See https://github.com/flintlib/flint/issues/2340
+export CFLAGS="$CFLAGS -fno-strict-aliasing"
+
 sdh_configure
 sdh_make
diff --git a/build/pkgs/singular/patches/flint-3.3.0-compatibility.patch b/build/pkgs/singular/patches/flint-3.3.0-compatibility.patch
new file mode 100644
index 00000000000..588e130c837
--- /dev/null
+++ b/build/pkgs/singular/patches/flint-3.3.0-compatibility.patch
@@ -0,0 +1,26 @@
+diff --git a/factory/FLINTconvert.cc b/factory/FLINTconvert.cc
+index c36f6022d..67c271c5a 100644
+--- a/factory/FLINTconvert.cc
++++ b/factory/FLINTconvert.cc
+@@ -652,7 +652,7 @@ convertFacCFMatrix2Fq_nmod_mat_t (fq_nmod_mat_t M,
+   {
+     for(j=m.columns();j>0;j--)
+     {
+-      convertFacCF2nmod_poly_t (M->rows[i-1]+j-1, m (i,j));
++      convertFacCF2nmod_poly_t (fq_nmod_mat_entry (M, i-1, j-1), m (i,j));
+     }
+   }
+ }
+diff --git a/libpolys/polys/flintconv.cc b/libpolys/polys/flintconv.cc
+index 89152f5e4..56d527c16 100644
+--- a/libpolys/polys/flintconv.cc
++++ b/libpolys/polys/flintconv.cc
+@@ -331,7 +331,7 @@ void convSingMFlintFq_nmod_mat(matrix m, fq_nmod_mat_t M, const fq_nmod_ctx_t fq
+   {
+     for(j=MATCOLS(m);j>0;j--)
+     {
+-      convSingPFlintnmod_poly_t (M->rows[i-1]+j-1, MATELEM(m,i,j),r);
++      convSingPFlintnmod_poly_t (fq_nmod_mat_entry (M, i-1, j-1), MATELEM(m,i,j),r);
+     }
+   }
+ }