#duckdb #entity

bin+lib ayb

ayb makes it easy to create, host, and share embedded databases like SQLite and DuckDB

4 releases

0.1.4 Jun 4, 2023
0.1.3 Apr 28, 2023
0.1.2 Apr 23, 2023
0.1.1 Apr 17, 2023

#383 in Database interfaces

24 downloads per month


912 lines


With ayb, all your base can finally belong to you. Move SQL for great justice.

Build status


ayb makes it easy to create databases, share them with collaborators, and query them from a web application or the command line. An ayb server allows users or organizations to create SQLite databases (other databases to come), and then exposes those databases through an HTTP API. In database terms, ayb is a multi-tenant RDBMS that relies on embedded databases like SQLite for persistence and query processing while exposing those databases over HTTP.

alpha warning: ayb is neither feature complete nor production-ready. Functionality like authentication, permissions, isolation, high availability, transaction support, collaboration, or DuckDB hosting are on the Roadmap but not available today. I work on ayb as a hobbyist side project.

Getting started


ayb is written in Rust, and is available as the ayb crate. Assuming you have installed Rust on your machine, installing ayb takes a single command:

cargo install ayb

Running the server

An ayb server stores its metadata in SQLite or PostgreSQL, and its embedded databases on a local disk. First, create an ayb.toml configuration file to tell the server what host/port to listen for connections on, how to connect to the database, and the data path for the embedded databases:

cat <<EOF > ayb.toml
host = ""
port = 5433
database_url = "sqlite://ayb_data/ayb.sqlite"
# Or, for Postgres:
# database_url = "postgresql://postgres_user:test@localhost:5432/test_db"
data_path = "./ayb_data"

Running the server then requires one command

$ ayb server

Running the client

Once the server is running, you can set its URL as an environment variable called AYB_SERVER_URL, register a user (in this case, marcua), create a database marcua/test.sqlite, and issue SQL as your heart pleases. Here's how to do that at the command line:

$ export AYB_SERVER_URL=

$ ayb client register marcua
Successfully registered marcua

$ ayb client create_database marcua/test.sqlite
Successfully created marcua/test.sqlite

$ ayb client query marcua/test.sqlite "CREATE TABLE favorite_databases(name varchar, score integer);"

Rows: 0

$ ayb client query marcua/test.sqlite "INSERT INTO favorite_databases (name, score) VALUES (\"PostgreSQL\", 10);"

Rows: 0

$ ayb client query marcua/test.sqlite "INSERT INTO favorite_databases (name, score) VALUES (\"SQLite\", 9);"

Rows: 0

$ ayb client query marcua/test.sqlite "INSERT INTO favorite_databases (name, score) VALUES (\"DuckDB\", 9);"

Rows: 0

$ ayb client query marcua/test.sqlite "SELECT * FROM favorite_databases;"
 name       | score 
 PostgreSQL | 10 
 SQLite     | 9 
 DuckDB     | 9 

Rows: 3

The command line invocations above are a thin wrapper around ayb's HTTP API. Here are the same commands as above, but with curl:

$ curl -w "\n" -X POST -H "entity-type: user"


$ curl -w "\n" -X POST -H "db-type: sqlite"


$ curl -w "\n" -X POST -d 'CREATE TABLE favorite_databases(name varchar, score integer);'


$ curl -w "\n" -X POST -d "INSERT INTO favorite_databases (name, score) VALUES (\"PostgreSQL\", 10);"


$ curl -w "\n" -X POST -d "INSERT INTO favorite_databases (name, score) VALUES (\"SQLite\", 9);"


$ curl -w "\n" -X POST -d "INSERT INTO favorite_databases (name, score) VALUES (\"DuckDB\", 9);"


$ curl -w "\n" -X POST -d "SELECT * FROM favorite_databases;"


What's with the name?

Thank you for asking. I hope the answer elicits some nostalgia! Shout out to Meelap Shah and Eugene Wu for convincing me to not call this project stacks, to Andrew Lange-Abramowitz for making the connection to the storied meme, and to Meredith Blumenstock for listening to me fret over it all.


Here's a rough roadmap for the project, with items near the top of the list more likely to be completed first. The nitty-gritty list of prioritized issues can be found on this project board, with the most-likely-to-be-completed issues near the top of the to-do list.

  • Make the single-user ayb experience excellent
    • Reduce reliance on PostgreSQL (SQLite metadata storage). Given that the goal of ayb is to make it easier to create, share, and query databases, it's frustrating that running ayb requires you to pay the nontrivial cost of operationalizing PostgreSQL. While Postgres will be helpful for eventually coordinating between multiple ayb nodes, a single-node version should be able to store its metadata in SQLite with little setup costs.
    • Authentication and permissions. Add authentication/the ability to log in, and add permissions to endpoints so that you can't just issue queries against any database.
    • Clustering. Support for multiple ayb nodes to serve databases and requests. Whereas a single database will not span multiple machines, parallelism/distribution will happen across users and databases.
    • Persistence beyond the node. Using projects like LiteFS, stream updates to databases to persistent storage, and allow failover if an ayb node disappears.
    • Isolation. Since an ayb instance can have multiple tenants/databases, we want to use one of the many container/isolate/microVM projects to ensure that one tenant isn't able to access another tenant's data.
    • Sessions/transactions. ayb's query API is a stateless request/response API, making it impossible to start a database transaction or issue multiple queries in a session. Exposing sessions in the API will allow multiple statements per session, and by extension, transactions.
    • Import/export of databases. ayb already uses existing well-established file formats (e.g., SQLite). There should be endpoints to import existing databases into ayb in those formats or export the underlying files so you're not locked in.
  • Extend ayb to more people and software
    • Collaboration. In addition to making it easy to create and query databases, it should be easy to share databases with others. Two use cases include adding private collaborators and allowing public read-only access.
    • Forking. Allowing a user to fork their own copy of a database will enable collaborators to remix and build on each others' work.
    • Versioning. To both make it less scary to execute sensitive operations and to make it possible for scientists to reference and publish checkpoints of their work, a user should be able to snapshot and revert to a database at a point in time.
    • DuckDB. Allowing users to create a DuckDB database in addition to a SQLite database would allow you to create a data warehouse with a single command. This effort is dependent on the DuckDB project. First, the DuckDB file format is rapidly changing ahead of the project's 1.0 release. Additionally, I don't know of an equivalent streaming replication project to LiteFS for DuckDB that handles persistence beyond the node.
    • PostgreSQL wire protocol. While an HTTP API makes it easy to build new web apps, exposing ayb over the PostgreSQL wire protocol will allow existing tools and libraries to connect to and query an ayb database.
  • Increase discoverability with a web frontend
    • Provide a web interface analogous to the command line interface. Much like GitHub/Gitea/Forgejo make git more approachable, you shouldn't have to pay a command line knowledge tax in order to create, share, and query an ayb database.
    • Explore people's public datasets. Beyond simplifying the command line, platforms like GitHub also make it easier to find a user's publicly shared repositories, follow along in their work, and fork a copy for your own exploration. That same experience should be possible for ayb-hosted databases.


(This section is inspired by the LiteFS project, and is just one of the many things to love about that project.)

ayb contributions work a little different than most GitHub projects:

  • If you have a small bug fix or typo fix, please PR directly to this repository.
  • If you want to contribute documentation, please PR directly to this repository.
  • If you would like to contribute a feature, create and discuss the feature in an issue on this GitHub repository first. Once the feature and some of its finer details are hashed out in the issue and potentially a design document, submit a pull request. I might politely decline pull requests that haven't first been discussed/designed.

This project has a roadmap and features are added and tested in a certain order. I'm adding a little friction in requiring a discussion/design document for features before submitting a pull request to ensure that I can focus my attention on well-motivated, well-sequenced, and well-understood functionality.


~1M SLoC