A very simple attempt at an (in-memory, at least so far) database that has support for algebraic datatypes.
More information here and here.
In one terminal, start the server:
cargo run -- --port 8080
In another, start the client:
$ cargo run --bin pdbcli -- -d localhost:8080
Welcome to pdbcli!
Connected to localhost:8080!
>> create table user Int
Created
>> insert let x = 4 in x end into user
Inserted 1
>> select from user
[4]
>> insert let f = lambda x -> lambda y -> x in f 42 43 end into user
Inserted 1
>> select from user
[4, 42]