# \#reltool **URL:** https://erlangforums.com/tag/reltool/544.md [Latest](https://erlangforums.com/latest.md) · [Categories](https://erlangforums.com/categories.md) · [Tags](https://erlangforums.com/tags.md) --- ## [Do we need both bin/erl and bin/dyn\_erl in Erlang/OTP?](https://erlangforums.com/t/do-we-need-both-bin-erl-and-bin-dyn-erl-in-erlang-otp/2066)
**Author:** [@josevalim](https://erlangforums.com/u/josevalim)\ **Replies:** 2\ **Last updated:** [December 18, 2022, 1:14pm UTC](https://erlangforums.com/t/do-we-need-both-bin-erl-and-bin-dyn-erl-in-erlang-otp/2066 "2022-12-18T13:14:27Z")
Erlang/OTP 25 makes it so Erlang releases are relocatable by default. It does so by calling bin/dyn\_erl --realpath. bin/dyn\_erl is a version of bin/erl implemented in C. When using reltool, you can also mark a release a…