### Setup PostgreSQL (Arch)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs and starts the PostgreSQL service on Arch-based systems. Includes steps for manual data directory initialization if needed.

```bash
sudo pacman -S postgresql
sudo systemctl start postgresql
# If the systemctl command errors, then run the following
sudo mkdir /var/lib/postgres/data
sudo chown postgres:postgres /var/lib/postgres/data
sudo -u postgres initdb -D /var/lib/postgres/data
sudo systemctl start postgresql
```

--------------------------------

### Setup PostgreSQL (Debian)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs and starts the PostgreSQL service on Debian-based systems.

```bash
sudo apt install postgresql
sudo systemctl start postgresql
```

--------------------------------

### Setup PostgreSQL (macOS)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs PostgreSQL using Homebrew and starts the service. Also creates a superuser role.

```bash
brew install postgresql
brew services start postgresql
$(brew --prefix postgresql)/bin/createuser -s postgres
```

--------------------------------

### Install Frontend Dependencies and Run Dev Server

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs frontend dependencies using pnpm and starts the lemmy-ui development server. The UI connects to the backend on localhost:8536 and is accessible at localhost:1234.

```bash
pnpm i
pnpm dev
```

--------------------------------

### Copy and Edit Environment File

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/on_aws.md

Copy the example environment file and edit it with your site settings before proceeding with the installation.

```shell
cp example.env.local .env.local
# edit .env.local
```

--------------------------------

### Install Docker and Clone Lemmy Repository (Arch)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/03-docker-development.md

Installs necessary packages like git and docker-compose, and starts the Docker service on Arch-based systems. Cloning the repository is a separate step.

```bash
sudo pacman -S git docker-compose
sudo systemctl start docker
```

--------------------------------

### Install Docker and Clone Lemmy Repository (Debian)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/03-docker-development.md

Installs necessary packages like git and docker-compose, starts the Docker service, and clones the Lemmy repository with submodules on Debian-based systems.

```bash
sudo apt install git docker-compose
sudo systemctl start docker
git clone https://github.com/LemmyNet/lemmy --recursive
```

--------------------------------

### Enable and Start Tor Daemon

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Enables the Tor service to start on boot and starts it immediately.

```bash
systemctl enable --now tor
```

--------------------------------

### Enable and Start Lemmy UI Service

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Reloads the systemd daemon, enables the Lemmy UI service to start on boot, and then starts the service.

```bash
sudo systemctl daemon-reload
sudo systemctl enable lemmy-ui
sudo systemctl start lemmy-ui
```

--------------------------------

### Install AWS CDK and Deploy Lemmy

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/on_aws.md

Install the AWS CDK globally, install project dependencies, bootstrap the CDK, and deploy the stack to your AWS account.

```shell
npm install -g aws-cdk
npm install
cdk bootstrap
cdk deploy
```

--------------------------------

### Enable and Start Lemmy Service

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Reloads the systemd daemon, enables the Lemmy service to start on boot, and then starts the service immediately.

```bash
sudo systemctl daemon-reload
sudo systemctl enable lemmy
sudo systemctl start lemmy
```

--------------------------------

### Install Prerequisite Packages

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Installs necessary packages for adding external APT repositories.

```bash
apt install -y apt-transport-https ca-certificates gpg lsb-release wget
```

--------------------------------

### Install pgFormatter (Arch)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs the pgFormatter tool on Arch-based systems.

```bash
sudo pacman -S pgformatter
```

--------------------------------

### Community List Example

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/04-api.md

Example of how to list communities using the API with a GET request.

```APIDOC
## GET /api/{version}/community/list

### Description
Retrieves a list of communities, sortable by various criteria.

### Method
GET

### Endpoint
`/api/{version}/community/list`

### Parameters
#### Query Parameters
- **sort** (string) - Optional - The sorting criteria for the community list (e.g., 'Hot').

### Request Example
```bash
curl "https://lemmy.ml/api/{version}/community/list?sort=Hot"
```
```

--------------------------------

### Install Node.js (macOS)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs Node.js using Homebrew on macOS.

```bash
brew install node
```

--------------------------------

### Start Local Federation Instances

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/03-docker-development.md

Starts multiple local Lemmy instances for testing federation functionality. Navigate to the 'docker/federation' directory before running.

```bash
cd docker/federation
./start-local-instances.bash
```

--------------------------------

### Install Taplo CLI

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs the Taplo TOML toolkit command-line interface using Cargo.

```bash
cargo install taplo-cli --locked
```

--------------------------------

### Install pgFormatter (Debian)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs the pgFormatter tool on Debian-based systems.

```bash
sudo apt install pgformatter
```

--------------------------------

### Install PostgreSQL Dependencies

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Installs necessary packages for PostgreSQL and adds the official PostgreSQL repository. Ensure you have wget and GPG keys configured.

```bash
sudo apt install -y wget ca-certificates pkg-config
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ $(lsb_release -cs)-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'
sudo apt update
sudo apt install libssl-dev libpq-dev postgresql
```

--------------------------------

### Install pgFormatter (macOS)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs the pgFormatter tool on macOS using Homebrew.

```bash
brew install pgformatter
```

--------------------------------

### Install Build Requirements (Arch)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs necessary build tools and libraries for Arch-based systems.

```bash
sudo pacman -S git cargo pkg-config postgresql-libs curl jq
```

--------------------------------

### Install Tor

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Updates package lists and installs the Tor daemon.

```bash
apt update && apt install -y tor
```

--------------------------------

### Install Build Requirements (Fedora)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs necessary build tools and libraries for Fedora-based systems.

```bash
sudo dnf install git cargo pkg-config libpq-devel curl postgresql-server postgresql-contrib jq
```

--------------------------------

### Setup Lemmy PostgreSQL Database

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Creates a dedicated user and database for Lemmy in PostgreSQL. Remember to replace 'db-passwd' with a strong, unique password.

```bash
sudo -iu postgres psql -c "CREATE USER lemmy WITH PASSWORD 'db-passwd';"
sudo -iu postgres psql -c "CREATE DATABASE lemmy WITH OWNER lemmy;"
```

--------------------------------

### Starting Lemmy_server HTTP servers

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/horizontal_scaling.md

These commands start Lemmy_server processes configured to handle HTTP requests, disabling activity sending and scheduled tasks for each instance.

```bash
# 3 http servers
lemmy_server --disable-activity-sending --disable-scheduled-tasks
lemmy_server --disable-activity-sending --disable-scheduled-tasks
lemmy_server --disable-activity-sending --disable-scheduled-tasks
```

--------------------------------

### Install Build Requirements (Debian)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs necessary build tools and libraries for Debian-based systems.

```bash
sudo apt install git cargo pkg-config libpq-dev curl jq
```

--------------------------------

### Install pnpm Globally

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Installs the pnpm package manager globally using npm.

```bash
npm install -g pnpm
```

--------------------------------

### Install Node.js 20 and pnpm

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Installs Node.js version 20 and the pnpm package manager on Ubuntu systems, as repository versions are often outdated.

```bash
# nodejs
sudo apt install -y ca-certificates curl gnupg
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg
echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_20.x nodistro main" | sudo tee /etc/apt/sources.list.d/nodesource.list

sudo apt update
sudo apt install nodejs

# pnpm
npm i -g pnpm
```

--------------------------------

### Install Nginx and Certbot

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Installs Nginx and Certbot for managing web server and TLS certificates.

```bash
sudo apt install nginx certbot python3-certbot-nginx
```

--------------------------------

### Comment Like Example

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/04-api.md

Example of how to like a comment using the API with a POST request.

```APIDOC
## POST /api/{version}/comment/like

### Description
Allows a user to like or unlike a comment.

### Method
POST

### Endpoint
`/api/{version}/comment/like`

### Parameters
#### Request Body
- **comment_id** (integer) - Required - The ID of the comment to like.
- **score** (integer) - Required - The score to apply (1 for like, -1 for dislike).
- **auth** (string) - Required - Authentication token.

### Request Example
```json
{
  "comment_id": 374,
  "score": 1,
  "auth": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpZCI6MiwiaXNzIjoidGVzdC5sZW1teS5tbCJ9.P77RX_kpz1a_geY5eCp29sl_5mAm-k27Cwnk8JcIZJk"
}
```
```

--------------------------------

### Install ImageMagick for pict-rs (AppImage)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Installs ImageMagick version 7 using an AppImage, which is required for pict-rs image hosting. Note that AppImage installations may not work in standard LXC containers due to FUSE limitations.

```bash
sudo apt install ffmpeg exiftool libgexiv2-dev --no-install-recommends
# save the file to a working folder it can be verified before copying to /usr/bin/
wget https://download.imagemagick.org/ImageMagick/download/binaries/magick
# compare hash with the "message digest" on the official page linked above
sha256sum magick
sudo mv magick /usr/bin/
sudo chmod 755 /usr/bin/magick
```

--------------------------------

### Clone and Build Lemmy UI

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Clones the lemmy-ui repository, checks out a specific version, installs dependencies using pnpm, and builds the production version.

```bash
# dont compile as admin
cd /opt/lemmy
sudo -u lemmy bash
git clone https://github.com/LemmyNet/lemmy-ui.git --recursive
cd lemmy-ui
git checkout 0.18.5 # replace with the version you want to install
pnpm i
pnpm build:prod
exit
```

--------------------------------

### Download Default Configuration Files

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/install_docker.md

Download the default Docker Compose file, configuration template, and Nginx configuration files. These files serve as the base for your Lemmy installation.

```bash
wget https://raw.githubusercontent.com/LemmyNet/lemmy-docs/main/assets/docker-compose.yml
wget https://raw.githubusercontent.com/LemmyNet/lemmy-ansible/main/examples/config.hjson -O lemmy.hjson
wget https://raw.githubusercontent.com/LemmyNet/lemmy-ansible/main/templates/nginx_internal.conf
wget https://raw.githubusercontent.com/LemmyNet/lemmy-ansible/main/files/proxy_params
```

--------------------------------

### Install Rust Build Dependencies

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Installs essential build tools for Rust compilation, including protobuf-compiler and GCC. This is necessary for compiling Lemmy and its dependencies.

```bash
sudo apt install protobuf-compiler gcc
```

--------------------------------

### Add ruby annotations

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/users/02-media.md

Use curly brace syntax or ruby tags to add pronunciation or translation guides.

```markdown
{Ruby|text}
```

```html
<ruby>Ruby<rt>text</rt></ruby>
```

--------------------------------

### Start Lemmy Docker Containers

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/install_docker.md

Start all the Docker containers defined in the docker-compose.yml file in detached mode. This command brings up the Lemmy instance and its associated services.

```bash
docker compose up -d
```

--------------------------------

### Compile and Install Lemmy Server

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Updates Rust toolchain, pulls the latest Lemmy code, checks out a specific version, builds the release binary, and replaces the running server binary.

```bash
rustup update
cd lemmy
git checkout main
git pull --tags
git checkout 0.18.5 # replace with version you are updating to
git submodule update
cargo build --release
# copy compiled binary to destination
# the old file will be locked by the already running application, so this sequence is recommended:
sudo -- sh -c 'systemctl stop lemmy && cp target/release/lemmy_server /opt/lemmy/lemmy-server/lemmy_server && systemctl start lemmy'
```

--------------------------------

### Starting Lemmy_server scheduled tasks process

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/horizontal_scaling.md

This command starts a Lemmy_server process dedicated to scheduled tasks, disabling its HTTP server and activity sending capabilities.

```bash
# scheduled tasks
lemmy_server --disable-http-server --disable-activity-sending
```

--------------------------------

### List Communities (GET)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/04-api.md

Use this endpoint to list communities. The `sort` parameter can be used to order the results.

```bash
curl "https://lemmy.ml/api/{version}/community/list?sort=Hot"
```

--------------------------------

### Image Proxy

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/09-api-v4.md

Image proxying is now handled by `GET /api/v4/image/proxy`.

```APIDOC
## Image Proxy

### Description
Proxies an image request.

### Method
GET

### Endpoint
/api/v4/image/proxy
```

--------------------------------

### Upgrade Lemmy UI

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Updates Lemmy UI to the latest version by pulling changes, installing dependencies, and rebuilding the production assets. Assumes running as the `lemmy` user.

```bash
cd /opt/lemmy/lemmy-ui
sudo -u lemmy bash
git checkout main
git pull --tags
git checkout 0.18.5 # replace with the version you are updating to
git submodule update
pnpm install
pnpm build:prod
exit
sudo systemctl restart lemmy-ui
```

--------------------------------

### Initialize PostgreSQL Database

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Creates a 'lemmy' user and database with specified password and sets the database URL environment variable.

```bash
psql -c "create user lemmy with password 'password' superuser;" -U postgres
psql -c 'create database lemmy with owner lemmy;' -U postgres
export LEMMY_DATABASE_URL=postgres://lemmy:password@localhost:5432/lemmy
```

--------------------------------

### Create Lemmy Directories

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Sets up the required directory structure in `/opt/lemmy` for the Lemmy server and its associated files, including directories for pict-rs.

```bash
sudo mkdir /opt/lemmy
sudo mkdir /opt/lemmy/lemmy-server
sudo mkdir /opt/lemmy/pictrs
sudo mkdir /opt/lemmy/pictrs/files
sudo mkdir /opt/lemmy/pictrs/sled-repo
sudo mkdir /opt/lemmy/pictrs/old
sudo chown -R lemmy:lemmy /opt/lemmy
```

--------------------------------

### Create Lemmy Directory

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/install_docker.md

Create a directory for Lemmy files and navigate into it. This is the first step in setting up the Docker environment.

```bash
mkdir lemmy
cd lemmy
```

--------------------------------

### Run Federation and API Tests

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Navigates to the `api_tests` directory and runs the federation test script.

```bash
cd api_tests
./run-federation-test.sh
```

--------------------------------

### Download Database Optimization Tool

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/install_docker.md

Download a configuration file for optimizing the PostgreSQL database. This file can be used with tuning tools to adjust database parameters based on system specifications.

```bash
wget https://raw.githubusercontent.com/LemmyNet/lemmy-ansible/main/examples/customPostgresql.conf
```

--------------------------------

### Configure Hosts for Federation Tests

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Adds entries to the `/etc/hosts` file to map hostnames to localhost for federation and API testing.

```bash
127.0.0.1       lemmy-alpha
127.0.0.1       lemmy-beta
127.0.0.1       lemmy-gamma
127.0.0.1       lemmy-delta
127.0.0.1       lemmy-epsilon
```

--------------------------------

### Get My User Information

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/09-api-v4.md

The `my_user` field has been removed from the `/api/v4/site` endpoint. User-specific information is now available via the `GET /api/v4/account` endpoint.

```APIDOC
## Get My User Information

### Description
Retrieves the current authenticated user's information.

### Method
GET

### Endpoint
/api/v4/account
```

--------------------------------

### Enable Tor Repository

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Configures APT to use the official deb.torproject.org repository for Tor packages.

```bash
bash -c 'dist=$(lsb_release -s -c); /bin/echo -e "deb [signed-by=/usr/share/keyrings/tor-archive-keyring.gpg] \
https://deb.torproject.org/torproject.org $dist main\n\ndeb-src [signed-by=/usr/share/keyrings/tor-archive-keyring.gpg] https://deb.torproject.org/torproject.org $dist main" > /etc/apt/sources.list.d/tor.list'
```

--------------------------------

### Sample Backup Script

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/backup_and_restore.md

A script to perform both database backup via SSH and volume folder backup using rsync. Ensure `MY_USER`, `MY_IP`, `LEMMY_LOCATION`, `BACKUP_LOCATION`, and `INSTANCE_NAME` are correctly configured.

```bash
#!/bin/sh
# DB Backup
ssh MY_USER@MY_IP "docker compose exec postgres pg_dumpall -c -U lemmy" | gzip > ~/BACKUP_LOCATION/INSTANCE_NAME_dump_`date +%Y-%m-%d"_"%H_%M_%S`.sql.gz

# Volumes folder Backup
rsync -avP -zz --rsync-path="sudo rsync" MY_USER@MY_IP:/LEMMY_LOCATION/volumes ~/BACKUP_LOCATION/FOLDERNAME
```

--------------------------------

### Image Retrieval

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/09-api-v4.md

Image retrieval is now handled by `GET /api/v4/image/{filename}`.

```APIDOC
## Image Retrieval

### Description
Retrieves an image file.

### Method
GET

### Endpoint
/api/v4/image/{filename}
```

--------------------------------

### Get Hidden Service Hostname

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Retrieves the `.onion` address assigned to the Tor hidden service.

```bash
cat /var/lib/tor/hidden_lemmy_service/hostname
```

--------------------------------

### Restore Database from .sql.gz Backup

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/backup_and_restore.md

Commands to restore a PostgreSQL database from a compressed SQL dump. Ensure the postgres container is running and then use `gunzip` and `psql` to import the data. Adjust permissions if necessary.

```bash
docker compose up -d postgres

# Restore from the .sql.gz backup
gunzip < db_dump.sql  |  docker compose exec -T postgres psql -U lemmy

# Note: You may need to change the permissions on the postgres directory, depending on your system.
chown -R $USER volumes
docker compose restart postgres

# Continue with the startup
docker compose up -d
```

--------------------------------

### Pictrs Image Deletion Token

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/04-api.md

This is an example of a delete token returned after an image upload, used for subsequent deletion requests.

```json
{
  "files": [
    {
      "delete_token": "{token}",
      "file": "{file}.jpg"
    }
  ],
  "msg": "ok"
}
```

--------------------------------

### Full Lemmy Configuration with Defaults

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/configuration.md

This snippet displays the complete configuration structure for Lemmy, including all default values. It serves as a reference for available settings.

```hjson
{{#include ../../lemmy/config/defaults.hjson}}
```

--------------------------------

### Become Root User

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Commands to switch to the root user for administrative tasks. Use `exit` to return to your account.

```bash
sudo -i
Password: [authenticate with current user password]
```

```bash
su -
Password: [authenticate with root's password]
```

--------------------------------

### Query Federation Queue State

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/troubleshooting.md

Execute this SQL query to get detailed information about the federation queue state for each instance. This helps identify instances that are not up to date.

```sql
select domain,currval('sent_activity_id_seq') as latest_id, last_successful_id,fail_count,last_retry from federation_queue_state
join instance on instance_id = instance.id order by last_successful_id asc;
```

--------------------------------

### Configure Plugins in lemmy.hjson

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/08-plugins.md

Specify plugins to be loaded by Lemmy in the configuration file. Includes plugin file URL, hash for verification, and allowed hosts.

```json
plugins: [{
  file: "https://github.com/LemmyNet/lemmy-plugins/releases/download/0.1.3/rust_lingua.wasm",
  hash: "e1f58029f2ecca5127a4584609494120683b691fc63a543979ea071f32cf690f",
  allowed_hosts: ["0.0.0.0"]
}]
```

--------------------------------

### Example Prometheus Metrics Output

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/prometheus.md

Sample output from the /metrics endpoint, illustrating HTTP request duration histograms and connection pool metrics. Note that each endpoint/method/status combination generates a histogram.

```text
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.005"} 0
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.01"} 0
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.025"} 5
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.05"} 10
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.1"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.25"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="0.5"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="1"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="2.5"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="5"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="10"} 12
lemmy_api_http_requests_duration_seconds_bucket{endpoint="/api/v3/post/list",method="GET",status="200",le="+Inf"} 12
lemmy_api_http_requests_duration_seconds_sum{endpoint="/api/v3/post/list",method="GET",status="200"} 0.3834808429999999
lemmy_api_http_requests_duration_seconds_count{endpoint="/api/v3/post/list",method="GET",status="200"} 12

lemmy_api_http_requests_total{endpoint="/api/v3/post/list",method="GET",status="200"} 12

# HELP lemmy_db_pool_available_connections Number of available connections in the pool
# TYPE lemmy_db_pool_available_connections gauge
lemmy_db_pool_available_connections 2
# HELP lemmy_db_pool_connections Current number of connections in the pool
# TYPE lemmy_db_pool_connections gauge
lemmy_db_pool_connections 2
# HELP lemmy_db_pool_max_connections Maximum number of connections in the pool
# TYPE lemmy_db_pool_max_connections gauge
lemmy_db_pool_max_connections 5

# HELP process_cpu_seconds_total Total user and system CPU time spent in seconds.
# TYPE process_cpu_seconds_total counter
process_cpu_seconds_total 14
# HELP process_max_fds Maximum number of open file descriptors.
# TYPE process_max_fds gauge
process_max_fds 1073741816
# HELP process_open_fds Number of open file descriptors.
# TYPE process_open_fds gauge
process_open_fds 91
```

--------------------------------

### Build Lemmy Backend

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Compiles the Lemmy backend in release mode using Cargo. This command should be run from the root of the cloned Lemmy repository.

```bash
cargo build --release
```

--------------------------------

### Download Traefik Docker Compose File

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/separate_subdomains.md

Use this command to download the Traefik Docker Compose file for setting up Lemmy on separate subdomains.

```bash
wget https://raw.githubusercontent.com/LemmyNet/lemmy-docs/main/assets/separate_subdomains/traefik/compose.yml
```

--------------------------------

### Configure Lemmy UI Backend URL

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/1.0_upgrade.md

Adjust Lemmy UI environment variables to point to the correct backend service. Ensure LEMMY_UI_BACKEND_INTERNAL points to the internal service address and LEMMY_UI_BACKEND to the public-facing URL.

```sh
- LEMMY_UI_BACKEND_INTERNAL=http://lemmy:8536
- LEMMY_UI_BACKEND=https://voyager.lemmy.ml
```

--------------------------------

### Full Database Backup

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/backup_and_restore.md

Use this command to create a compressed SQL dump of the entire PostgreSQL database. The backup file is named with a timestamp.

```bash
docker compose exec postgres pg_dumpall -c -U lemmy | gzip > lemmy_dump_`date +%Y-%m-%d"_"%H_%M_%S`.sql.gz
```

--------------------------------

### Run Multiple Lemmy Servers for Federation

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/horizontal_scaling.md

Configure multiple lemmy_server instances to distribute federation processing. Each instance should have a unique federate-process-index and the same federate-process-count.

```bash
lemmy_server --disable-http-server --disable-scheduled-tasks --federate-process-index=1 --federate-process-count=3
lemmy_server --disable-http-server --disable-scheduled-tasks --federate-process-index=2 --federate-process-count=3
lemmy_server --disable-http-server --disable-scheduled-tasks --federate-process-index=3 --federate-process-count=3
```

--------------------------------

### Create Lemmy System User

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Creates a dedicated system user account for the lemmy_server application. This user will run the Lemmy backend process.

```bash
sudo adduser lemmy --system --disabled-login --no-create-home --group
```

--------------------------------

### Instance Object Structure (ActivityPub)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/05-federation.md

Defines the structure of an Instance object in ActivityPub format, used for representing Lemmy instances in federated communication. Includes fields like name, summary, content, icon, inbox, and publicKey.

```json
{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "@language": "en"
    }
  ],
  "type": "Application",
  "name": "string",
  "summary": "string",
  "content": "string",
  "icon": {
    "type": "Image",
    "url": "string"
  },
  "image": {
    "type": "Image",
    "url": "string"
  },
  "inbox": "string",
  "endpoints": {
    "sharedInbox": "string"
  },
  "published": "string",
  "updated": "string",
  "publicKey": {
    "id": "string",
    "owner": "string",
    "publicKeyPem": "string"
  }
}
```

--------------------------------

### Verify Architecture Support

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/tor_hidden_service.md

Check if your system's architecture is supported by the Tor package repository.

```bash
dpkg --print-architecture
```

--------------------------------

### Automate Let's Encrypt Certificate Renewal

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Adds a daily cron job to renew Let's Encrypt certificates and reload Nginx. Replace `example.com` with your domain.

```bash
@daily certbot certonly --nginx --cert-name example.com -d example.com --deploy-hook 'nginx -s reload'
```

--------------------------------

### Download NGINX Internal Configuration

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/separate_subdomains.md

Use this command to download the NGINX internal configuration file. Remember to edit it to replace the resolver placeholder.

```bash
wget https://raw.githubusercontent.com/LemmyNet/lemmy-docs/main/assets/separate_subdomains/nginx/nginx_internal.conf
```

--------------------------------

### ActivityPub Context for Lemmy

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/05-federation.md

The ActivityPub context is identical for all activities and objects in Lemmy.

```json
"@context": [
    "https://join-lemmy.org/context.json",
    "https://www.w3.org/ns/activitystreams"
],
```

--------------------------------

### Run Prometheus Server (Local)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/prometheus.md

Command to run a Prometheus server locally, mounting a configuration file.

```shell
docker run -p 9090:9090 -v prometheus.yml:/etc/prometheus/prometheus.yml prom/prometheus
```

--------------------------------

### Test Lemmy Federation with Curl

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/first_steps.md

Use this command to verify that your instance's federation is working correctly. It should return JSON data, not an HTML file.

```bash
curl -H 'Accept: application/activity+json' https://your-instance.com/u/your-username
```

```bash
curl -H 'Accept: application/activity+json' https://lemmy.ml/u/nutomic
```

--------------------------------

### Useful CDK Commands

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/on_aws.md

A list of common AWS CDK commands for managing the Lemmy deployment, including building, watching, testing, deploying, diffing, and synthesizing.

```shell
npm run build
npm run watch
npm run test
cdk deploy
cdk diff
cdk synth
```

--------------------------------

### Nginx Configuration for ActivityPub Federation

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/troubleshooting.md

Set up your Nginx reverse proxy to correctly route ActivityPub requests, specifically those with 'application/activity+json' or 'application/ld+json' accept headers, to the appropriate Lemmy backend port.

```nginx
set $proxpass "http://0.0.0.0:{{ lemmy_ui_port }}";
if ($http_accept = "application/activity+json") {
set $proxpass "http://0.0.0.0:{{ lemmy_port }}";
}
if ($http_accept = "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"") {
set $proxpass "http://0.0.0.0:{{ lemmy_port }}";
}
proxy_pass $proxpass;
```

--------------------------------

### Clone Lemmy Repositories

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Clones the backend and frontend repositories, ensuring submodules are initialized.

```bash
git clone https://github.com/LemmyNet/lemmy.git --recursive
git clone https://github.com/LemmyNet/lemmy-ui.git --recursive
```

--------------------------------

### Build Custom Docker Image for Lemmy

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/03-docker-development.md

Builds a custom Docker image from the local Lemmy source code, tagging it with the current branch name. Use this to test modifications to the source code.

```bash
sudo docker build . -f docker/Dockerfile --build-arg RUST_RELEASE_MODE=release -t "lemmy:${git rev-parse --abbrev-ref HEAD}"
```

--------------------------------

### Minimal Lemmy Configuration

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Provides a basic configuration file for the Lemmy server. Ensure to replace placeholder values like database password and hostname.

```hjson
{
  database: {
    # put your db-passwd from above
    password: "db-passwd"
  }
  # replace with your domain
  hostname: example.com
  bind: "127.0.0.1"
  federation: {
    enabled: true
  }
  # remove this block if you don't require image hosting
  pictrs: {
    url: "http://localhost:8080/"
  }
}
```

--------------------------------

### Format and Lint Lemmy Backend

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Formats the Rust code using `cargo fmt` and runs the linter script.

```bash
cargo +nightly fmt --all
./scripts/lint.sh
```

--------------------------------

### Prometheus Configuration for Lemmy (Local)

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/prometheus.md

Minimal Prometheus server configuration to scrape metrics from a locally running Lemmy instance.

```yaml
global:
scrape_configs:
  - job_name: lemmy
    scrape_interval: 1m
    static_configs:
      - targets:
          - localhost:10002
```

--------------------------------

### Testing ActivityPub Endpoint

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/troubleshooting.md

Verify that your reverse proxy is correctly serving ActivityPub content by using curl to fetch local objects. Ensure these commands return valid JSON.

```bash
curl -H "Accept: application/activity+json" https://your-instance.com/u/some-local-user
curl -H "Accept: application/activity+json" https://your-instance.com/c/some-local-community
curl -H "Accept: application/activity+json" https://your-instance.com/post/123 # the id of a local post
curl -H "Accept: application/activity+json" https://your-instance.com/comment/123 # the id of a local comment
```

--------------------------------

### Configure Cargo for Faster Compilation

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/02-local-development.md

Adds configuration to `~/.cargo/config.toml` to use sccache and mold for faster Rust compilation. Note: `-Zthreads` requires nightly Rust.

```toml
[build]
rustc-wrapper = "/usr/bin/sccache"

[target.x86_64-unknown-linux-gnu]
linker = "clang"
rustflags = ["-C", "link-arg=-fuse-ld=/usr/bin/mold", "-Z", "threads=16"]
```

--------------------------------

### Initialize and Update Git Submodules

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/03-docker-development.md

Initializes and updates git submodules, which can resolve 'translations missing' errors during the Docker build process.

```bash
git submodule init && git submodule update
```

--------------------------------

### Obtain Let's Encrypt TLS Certificate

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/from_scratch.md

Requests a TLS certificate from Let's Encrypt. Follow the interactive prompts.

```bash
sudo certbot certonly --nginx
```

--------------------------------

### Apply subscript formatting

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/users/02-media.md

Use tilde syntax or sub tags for subscript text.

```markdown
Some ~subscript~ text
```

```html
Some <sub>subscript</sub> text
```

--------------------------------

### Run SQL Migration Down Script

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/troubleshooting.md

Execute a specific SQL migration script to reverse database changes during a downgrade. Ensure the path to the migrations directory is correct.

```bash
downfolder=2024-02-28-144211_hide_posts
psql -d lemmy -a -f /path/to/migrations/${downfolder}/down.sql
```

--------------------------------

### Announce Create Post Activity

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/contributors/05-federation.md

Forwards a 'Create' activity (like a new post) to a community's followers. The community acts as the 'actor' in this announcement.

```json
{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Announce",
  "actor": "https://sh.itjust.works/c/community_name",
  "to": [
    "https://sh.itjust.works/u/user_name/followers"
  ],
  "object": {
    "@context": [
      "https://www.w3.org/ns/activitystreams",
      {
        "lemmy": "https://joinlemmy.org/ns"
      }
    ],
    "type": "Create",
    "actor": "https://sh.itjust.works/u/post_author",
    "to": [
      "https://sh.itjust.works/c/community_name"
    ],
    "cc": [
      "https://sh.itjust.works/u/post_author/followers"
    ],
    "object": {
      "type": "Note",
      "content": "This is a new post.",
      "id": "https://sh.itjust.works/c/community_name/@post_author/post_id",
      "url": "https://sh.itjust.works/c/community_name/@post_author/post_id",
      "attributedTo": "https://sh.itjust.works/u/post_author",
      "to": [
        "https://sh.itjust.works/c/community_name"
      ],
      "cc": [
        "https://sh.itjust.works/u/post_author/followers"
      ],
      "published": "2023-01-01T12:00:00Z",
      "inbox": "https://sh.itjust.works/u/post_author/inbox"
    }
  }
}
```

--------------------------------

### Set Pictrs Folder Permissions

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/install_docker.md

Create the directory for pictrs uploads and set the correct ownership and permissions. This ensures that the Lemmy instance can properly handle image uploads.

```bash
mkdir -p volumes/pictrs
sudo chown -R 991:991 volumes/pictrs
```

--------------------------------

### Clear Existing Database

Source: https://github.com/lemmynet/lemmy-docs/blob/main/src/administration/backup_and_restore.md

Commands to drop the public schema and recreate it, or to change the user password. These are useful if you encounter issues during restoration or when importing with a different password.

```bash
# Drop the existing DB
docker exec -i FOLDERNAME_postgres_1 psql -U lemmy -c "DROP SCHEMA public CASCADE; CREATE SCHEMA public;"

# This also might be necessary when doing a db import with a different password.
docker exec -i FOLDERNAME_postgres_1 psql -U lemmy -c "alter user lemmy with password 'bleh'"
```