mailutils had this note to build it with sql. I picked mariadb, the attached patch builds alright. But: Why do we want this? mariadb adds *very much* to the size of the package and its dependencies. size before adding mariadb: store item total self /gnu/store/vz3zfmphvv4w4y7nffwr4jkk7k4s0rfs-guile-2.2.3 116.4 44.3 27.9% /gnu/store/2ifmksc425qcysl5rkxkbv6yrgc1w9cs-gcc-5.5.0-lib 60.4 30.1 18.9% /gnu/store/4sqaib7c2dfjv62ivrg9b8wa7bh226la-glibc-2.26.105-g0890d5379c 30.3 28.8 18.1% /gnu/store/xahax73vcsfnslqrb2s10szffn1f8zvv-mailutils-3.4 158.8 12.6 8.0% /gnu/store/dkdlrdkfi5n8w0xilf63nnz1jkcz0lxr-guile-2.0.14 84.6 12.5 7.9% /gnu/store/cfw4w2a30macx4lly4978298frdmaghl-ncurses-6.0-20170930 66.2 5.8 3.7% /gnu/store/1n59wjm6dbvc38b320iiwrxra3dg7yv8-libunistring-0.9.8 65.0 4.6 2.9% /gnu/store/i397mqhpihsx45c0cbqfsnlvp4q4fkm1-gnutls-3.5.13 124.0 4.4 2.8% /gnu/store/xh4k91vl0i8nlyrmvsh01x0mz629w5a9-gmp-6.1.2 63.1 2.7 1.7% /gnu/store/gwyb3679v49ljisgkvzay2xa3njgq4ii-linux-pam-1.3.0 63.3 1.9 1.2% /gnu/store/90vz0r78bww7dxhpa7vsiynr1rcqhyh4-nettle-3.4 64.9 1.8 1.2% /gnu/store/05dvazr5wfh7lxx4zi54zfqnx6ha8vxr-bash-static-4.4.12 1.5 1.5 0.9% /gnu/store/8bnpvbd1f926wy63kna8gr347nq04340-readline-7.0.3 67.5 1.3 0.8% /gnu/store/vgmln3b639r68vvy75xhcbi7d2w31mx1-pkg-config-0.29.2 61.7 1.3 0.8% /gnu/store/c4jrwbv7qckvnqa7f3h7bd1hh8rbg72y-libgc-7.6.0 62.2 1.2 0.8% /gnu/store/mm0zclrzj3y7rj74hzyd0f224xly04fh-bash-minimal-4.4.12 31.3 1.0 0.6% /gnu/store/p2iv444q6mpqsfaqwmzzhfcsxd81bqz5-gdbm-1.13 61.0 0.6 0.4% /gnu/store/zksh1n0p9x903kqbvswgwy2vsk2b7255-libatomic-ops-7.4.8 0.6 0.6 0.4% /gnu/store/ksyja5lbwy0mpskvn4rfi5klc00c092d-libidn2-2.0.4 65.5 0.5 0.3% /gnu/store/2fg01r58vv9w41kw6drl1wnvqg7rkv9d-libtasn1-4.12 60.8 0.4 0.3% /gnu/store/8hxm8am4ll05sa8wlwgdq2lj4ddag464-zlib-1.2.11 60.8 0.4 0.2% /gnu/store/0jawbsyafm93nxf4rcmkf1rsk7z03qfa-libltdl-2.4.6 60.5 0.2 0.1% /gnu/store/l15mx9lrwdflyvmb4a05va05v5yqizg5-libffi-3.2.1 60.5 0.1 0.1% total: 158.8 MiB size after adding mariadb: store item total self /gnu/store/1iqwxsj5k87av9pq1vvdls31i3gsavv4-mariadb-10.1.29 604.5 302.3 43.4% /gnu/store/x9x6vmspwx3d47m742ampja44pcs8ys9-gcc-5.5.0 182.7 93.2 13.4% /gnu/store/4paq5m3wnb6p8ch8jy9d0xdgh5fy19s6-perl-5.26.1 132.3 52.5 7.5% /gnu/store/vz3zfmphvv4w4y7nffwr4jkk7k4s0rfs-guile-2.2.3 116.4 44.3 6.4% /gnu/store/2ifmksc425qcysl5rkxkbv6yrgc1w9cs-gcc-5.5.0-lib 60.4 30.1 4.3% /gnu/store/xfjba1kww8ngdc6nxldd8ly93nh13ayy-gcc-5.5.0-lib 60.4 30.1 4.3% /gnu/store/4sqaib7c2dfjv62ivrg9b8wa7bh226la-glibc-2.26.105-g0890d5379c 30.3 28.8 4.1% /gnu/store/n6acaivs0jwiwpidjr551dhdni5kgpcr-glibc-2.26.105-g0890d5379c 30.3 28.8 4.1% /gnu/store/as7vb5xx7vqdwmmqj9543470r49b4c0c-coreutils-8.28 78.9 15.0 2.2% /gnu/store/2p0pwla1qg0ramf1ymi0jr43wq9hs82v-mailutils-3.4 695.8 12.7 1.8% /gnu/store/dkdlrdkfi5n8w0xilf63nnz1jkcz0lxr-guile-2.0.14 84.6 12.5 1.8% /gnu/store/4r565cg1pn2hfky0hb94mxyiqaygrlss-libxml2-2.9.7 72.9 10.0 1.4% /gnu/store/cfw4w2a30macx4lly4978298frdmaghl-ncurses-6.0-20170930 66.2 5.8 0.8% /gnu/store/1n59wjm6dbvc38b320iiwrxra3dg7yv8-libunistring-0.9.8 65.0 4.6 0.7% /gnu/store/i397mqhpihsx45c0cbqfsnlvp4q4fkm1-gnutls-3.5.13 124.0 4.4 0.6% /gnu/store/xh4k91vl0i8nlyrmvsh01x0mz629w5a9-gmp-6.1.2 63.1 2.7 0.4% /gnu/store/0rikh0izxyz1gq6s5x2kljid4zx6hqb9-gmp-6.1.2 63.1 2.7 0.4% /gnu/store/gwyb3679v49ljisgkvzay2xa3njgq4ii-linux-pam-1.3.0 63.3 1.9 0.3% /gnu/store/90vz0r78bww7dxhpa7vsiynr1rcqhyh4-nettle-3.4 64.9 1.8 0.3% /gnu/store/05dvazr5wfh7lxx4zi54zfqnx6ha8vxr-bash-static-4.4.12 1.5 1.5 0.2% /gnu/store/8bnpvbd1f926wy63kna8gr347nq04340-readline-7.0.3 67.5 1.3 0.2% /gnu/store/vgmln3b639r68vvy75xhcbi7d2w31mx1-pkg-config-0.29.2 61.7 1.3 0.2% /gnu/store/c4jrwbv7qckvnqa7f3h7bd1hh8rbg72y-libgc-7.6.0 62.2 1.2 0.2% /gnu/store/pj8xqlnkwgjia87jy6i8slglip9k8x6a-xz-5.2.3 62.6 1.2 0.2% /gnu/store/mm0zclrzj3y7rj74hzyd0f224xly04fh-bash-minimal-4.4.12 31.3 1.0 0.1% /gnu/store/p2iv444q6mpqsfaqwmzzhfcsxd81bqz5-gdbm-1.13 61.0 0.6 0.1% /gnu/store/zksh1n0p9x903kqbvswgwy2vsk2b7255-libatomic-ops-7.4.8 0.6 0.6 0.1% /gnu/store/ksyja5lbwy0mpskvn4rfi5klc00c092d-libidn2-2.0.4 65.5 0.5 0.1% /gnu/store/i6qikcw1ilhsw4nngv8y2sz1z1z8my2d-acl-2.2.52 61.1 0.4 0.1% /gnu/store/2fg01r58vv9w41kw6drl1wnvqg7rkv9d-libtasn1-4.12 60.8 0.4 0.1% /gnu/store/08ajhq8c53k26rc8jhq904ply8j90ggw-zlib-1.2.11 30.7 0.4 0.1% /gnu/store/8hxm8am4ll05sa8wlwgdq2lj4ddag464-zlib-1.2.11 60.8 0.4 0.1% /gnu/store/8cg3lnnkmrbw5fj96pcgj23fmb5blxyi-attr-2.4.47 60.6 0.2 0.0% /gnu/store/0jawbsyafm93nxf4rcmkf1rsk7z03qfa-libltdl-2.4.6 60.5 0.2 0.0% /gnu/store/9n8rg8kaggy6vwv2gc7ckprr7x9w8v7i-libcap-2.25 60.5 0.2 0.0% /gnu/store/l15mx9lrwdflyvmb4a05va05v5yqizg5-libffi-3.2.1 60.5 0.1 0.0% /gnu/store/iwmvm96lgd2bp0lrk2i8kz5714d90wz3-libaio-0.3.110 0.1 0.1 0.0% total: 695.8 MiB -- A88C8ADD129828D7EAC02E52E22F9BBFEE348588 https://n0.is