# Rel8 1.8 released! > Source: > Published: 2026-09-22 00:34:18+00:00 [TeofilC](https://discourse.haskell.org/u/TeofilC) 1 Hi folks! We’re happy to announce the release of [Rel8 1.8](https://hackage.haskell.org/package/rel8-1.8.0.0) ! Rel8 is a Haskell library for interacting with PostgreSQL databases, built on top of the fantastic Opaleye library. The main objectives of Rel8 are: - Conciseness: Users using Rel8 should not need to write boiler-plate code. By using expressive types, we can provide sufficient information for the compiler to infer code whenever possible. - Inferrable: Despite using a lot of type level magic, Rel8 aims to have excellent and predictable type inference. - Familiar: writing Rel8 queries should feel like normal Haskell programming. I would like to highlight the new TH deriving functionality. This has been a long time coming, and can give very significant compile-time improvements. In the wild, I have seen it reduce the time taken to compile a module by 80%. It doesn’t yet support all of the use-cases of `Generics` deriving and is somewhat experimental, so feedback is greatly appreciated! If you encounter any issues please [let us know](https://github.com/circuithub/rel8/issues). Here’s the full changelog for this release: ## - Added `Rel8.TH.deriveRel8able` and`Rel8.TH.deriveRel8ables` for deriving`Rel8able` instances using`TemplateHaskell` . This can be significantly faster than using`Generics` . In testing, we have seen 80% reductions in build time! - Expose all `rel8` internal modules from the`rel8-internal` package. - Added new `Conflict` and`Index` types.`Conflict` represents a[`conflict_target`](https://www.postgresql.org/docs/current/sql-insert.html#SQL-ON-CONFLICT) in an`ON CONFLICT` . It can be either a named constraint (`ON CONSTRAINT` ) or a an`Index` . - Added `Index` .`Index` is a description of a unique index which PostgreSQL can use for*unique index inference* . This is an alternative to specifying an explicit named constraint in a`conflict_target` . - Add `notElem` and`notElem1` to`Rel8.Array` - Added preliminary support for PostgreSQL ranges. - Support GHC-9.14 and `semialign >= 1.4` . - Added `notElem` and`notElem1` to`Rel8.Array` . - Added `DBType Aeson.Object` instance. - Bumped a variety of bounds. ## - The `Upsert` type was changed. Previously it had the columns (`index` ,`predicate` ) of what is now the`Index` type baked into its record. It now instead has a single`conflict` column (of type`Conflict` , which can be either an`Index` or a named constraint). - The `DoNothing` constructor of`OnConflict` was changed to also take an optional`Conflict` value. Even though`ON CONFLICT DO NOTHING` does not generally require a`conflict_target` , there are cases where it can be necessary, e.g., if you have table that has both deferrable and non-deferrable constraints. - `rel8` now requires at least version`0.10.8.0` of`opaleye` ## - `elem` and`elem1` now use`IS NOT DISTINCT FROM` semantics (matching`(==.)` ) when the element type is nullable, so`null` is found in an array containing`null` . Previously they were implemented with the array containment operator`<@` , which never matches`null` . - Fixed some issues around the truncation of long column names. - Improved documentation. 21 Likes [jackdk](https://discourse.haskell.org/u/jackdk) 2 `rel8` is my favourite Haskell DB library because it’s managed to avoid becoming a type labyrinth most of the time, but you still get a lot of power and safety. Congrats on the new release.