# Modifying & extending LAMMPS

LAMMPS has a modular design, so that it is easy to modify or extend with
new functionality. In fact, about 95% of its source code is optional.
The following pages give basic instructions on adding new features to
LAMMPS. More in-depth explanations and documentation of individual
functions and classes are given in [Developer]{.title-ref}.

If you add a new feature to LAMMPS and think it will be of general
interest to other users, we encourage you to submit it for inclusion in
LAMMPS. This process is explained in the following three pages:

-   [how to prepare and submit your code](Modify_contribute)
-   [requirements for submissions](Modify_requirements)
-   [style guidelines](Modify_style)

A summary description of various types of styles in LAMMPS follows. A
discussion of implementing specific styles from scratch is given in
[writing new styles](Developer_write).

::: {.toctree maxdepth="1"}
Modify_overview Modify_contribute Modify_requirements Modify_style
:::

::: {.toctree maxdepth="1"}
Modify_atom Modify_pair Modify_bond Modify_compute Modify_fix
Modify_command Modify_dump Modify_kspace Modify_min Modify_region
Modify_body Modify_gran_sub_mod Modify_thermo Modify_variable
:::