What's Changed Migrate to Pydantic v2 by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/964 Make Interchange.topology a required field by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/995 Collection ergonomics by @Yoshanuikabundi in https://github.com/openforcefield/openff-interchange/pull/990 Improve documentation of from_openmm and related features by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1008 [pre-commit.ci] pre-commit autoupdate by @pre-commit-ci in https://github.com/openforcefield/openff-interchange/pull/1025 Simplify access to Pydantic v1 API by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1026 Migrate formatting to ruff by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1032 Convenience methods for producing run input files by @Yoshanuikabundi in https://github.com/openforcefield/openff-interchange/pull/1027 Do not write vacuum simulations to GROMACS files by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1034 API cleanup by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1043 Add amber example by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1046 Add to_amber convenience method by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1041 Fix default .charges by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1066 Use update instead of assignment to set _charges by @ntBre in https://github.com/openforcefield/openff-interchange/pull/1069 Log packing failures by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1067 Error if HMR results in negative particle mass by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1065 Clarify to_openmm_simulation docstring and rename to_lammps(file_path) arg to prefix by @Yoshanuikabundi in https://github.com/openforcefield/openff-interchange/pull/1042 Fix regression tests by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1073 Add high-level positions getter, exclude virtual sites by default by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1074 Export positions with virtual sites by default by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1078 Decrease default density in Packmol wrappers by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1068 Update topology/system particle bookkeeping in OpenMM by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1051 Document that topology charges are ignored by @mattwthompson in https://github.com/openforcefield/openff-interchange/pull/1064 New Contributors @ntBre made their first contribution in https://github.com/openforcefield/openff-interchange/pull/1069 Full Changelog: https://github.com/openforcefield/openff-interchange/compare/v0.3.29...v0.4.0rc1

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