Hi guys! Here is yet another some-level library to work with PostgreSQL DB. http://hackage.haskell.org/package/postgresql-query This library uses `postgresql-query` and is a list of helpers/workarounds to generate complex queries more safely and parse result. What it contains: 1. interplating quasiquote `sqlExp` which uses instances of `ToField` typeclass to paste values inside query. It looks like this: let val = "'hello'" :: Text q = [sqlExp|SELECT field1 FROM tbl WHERE field2 = #{val}|] where `val` is an arbitrary Haskell expression which type has instance of `ToField` Resulting query will be like: "SELECT field1 FROM tbl WHERE field2 = '''hello'''" Yes, proper string escaping is performed authomatically like using this '?'-like queries with parameters. Resulting type of quasiquote is `SqlBuilder` which uses bytestring builders inside and can be concatenated efficiently. There is also posibility to paste one query inside another like: let q2 = [sqlExp|SELECT field1 f FROM (^{q}) WHERE field1 is not null|] so `q2` will generate nested query. sqlExp also removes SQL comments and removes long sequences of space characters. It also properly handles string literals and quoted identifiers inside quasiquotes. 2. Typeclass `HasPostgres`, simple connection reader `PgMonadT` and functions like `pgQuery` to perform queries. http://hackage.haskell.org/package/postgresql-query-1.0.1/docs/Database-Post... 3. TH functions to authomatically derive `FromRow` and `ToRow` instances (from postgresql-simple) http://hackage.haskell.org/package/postgresql-query-1.0.1/docs/Database-Post... 4. Some kind of primitive pre-ORM which generates queries for CRUD-ing simple record types. It looks like: data User = User { userName :: !Text , userPasswordEncrypted :: !Text } deriving (Show, Eq, Ord, Typeable) type UserId = EntityId User $(deriveFromRow ''User) $(deriveToRow ''User) instance Entity User where newtype EntityId User = UserId { unUserId :: UUID } -- Note that you can use any type for id deriving (Show, Read, Ord, Eq, FromField, ToField, PathPiece) -- To use with Yesod tableName _ = "users" fieldNames _ = [ "name" , "password_encrypted" ] runPgMonadT con $ do uid <- pgInsertEntity $ User "name" "j27dna74ja784ha7" pgUpdateEntity uid $ MR [("name", mkValue "John")] pgDeleteEntity uid There is also package http://hackage.haskell.org/package/postgresql-config which contains trivial code to make your postgresql-simple connection pool easily configurable.