gopglite

gopglite ALPHA ALPHA WIP EXPERIMENT

A Go database/sql/driver for PGlite, an embedded PostgreSQL compiled to WebAssembly.

DO NOT USE -- this is largely an AI-generated experiment.

Features

• Pure Go - Uses wazero as the WebAssembly runtime (no cgo required)
• Embedded PostgreSQL - Full PostgreSQL 16 running in-process
• Standard database/sql interface - Works with existing Go database code
• PL/pgSQL support - Full procedural language support
• Extensions - Includes encoding converters, snowball text search, etc.

Installation

go get github.com/bradfitz/gopglite

Usage

package main

import (
    "database/sql"
    "fmt"
    _ "github.com/bradfitz/gopglite"
)

func main() {
    db, err := sql.Open("pglite", ":memory:")
    if err != nil {
        panic(err)
    }
    defer db.Close()

    // Create a table
    _, err = db.Exec(`CREATE TABLE users (
        id SERIAL PRIMARY KEY,
        name TEXT NOT NULL
    );`)
    if err != nil {
        panic(err)
    }

    // Insert data
    _, err = db.Exec(`INSERT INTO users (name) VALUES ('Alice');`)
    if err != nil {
        panic(err)
    }

    // Query data back
    rows, err := db.Query(`SELECT id, name FROM users;`)
    if err != nil {
        panic(err)
    }
    defer rows.Close()

    for rows.Next() {
        var id int64
        var name string
        if err := rows.Scan(&id, &name); err != nil {
            panic(err)
        }
        fmt.Printf("id=%d, name=%s\n", id, name)
    }
    // Output: id=1, name=Alice
}

Status

Working:

• Opening databases
• Executing DDL (CREATE TABLE, etc.)
• Executing DML (INSERT, UPDATE, DELETE)
• Reading query results (via PostgreSQL wire protocol)
• Transactions (BEGIN, COMMIT, ROLLBACK)
• PL/pgSQL functions
• PostgreSQL extensions

Future:

• Prepared statements with parameter binding (currently uses query string formatting)

How it Works

This library embeds a WASI build of PGlite (PostgreSQL compiled to WebAssembly) and runs it using the wazero runtime. The WASI build includes:

• The PostgreSQL server binary (postgres.wasi)
• A pre-initialized data directory with system catalogs
• Extension libraries (encoding converters, text search, etc.)

When you open a database, the library:

1. Extracts the embedded PGlite environment to a temp directory
2. Creates a wazero runtime with WASI support
3. Mounts the filesystem directories
4. Calls pg_initdb to initialize/resume the database
5. Executes queries via the interactive_one function

Credits

• PGlite - The PostgreSQL WASM build by ElectricSQL
• pglite-bindings - Language bindings for PGlite
• pglite-go - Initial Go proof-of-concept
• wazero - Pure Go WebAssembly runtime

License

MIT License - see LICENSE