This is my code for running Screeps - an open-source sandbox MMO RTS game for programmers.

Code is written in TypeScript and was based on Screeps Typescript Starter.

To upload the code onto Screeps account you should:

1. Copy screeps.sample.json file and rename it to screeps.json.
2. Replace value of token property inside the file to the value of your Screeps token.
3. Execute npm run push-main or npm run push-test to upload code into Screeps main or test branch respectively.
4. Switch to the branch in Screeps.

Main code loop consists of executing 4 modules:

• Tower commanding

  Detects enemy creeps in occupied room and commands towers to attack them. If no enemies detected, repairs damaged structures

• Creep commanding

  Issues creeps commands based on their role and active task.

• Creep spawning

  Decides creeps of which roles should be spawned based on set targets and current creep counts.

• Memory cleanup

  Removes data from memory that is not needed any more.

Creeps are organized in roles and tasks.

Role is assigned to a creep upon spawning. Role is used to decide on what task the creep should work on.

Task is used to decide what creep should do. When task is assigned to a creep it finds its target and saves it to the creep memory. Each tick it works on the task and checks finish condition. If tasks is finished, new one will be assigned by the role.

The existing roles are:

Starter role. Will harvest energy from source and fill spawn, build, fill extensions and upgrade controller.

Used to build and maintain constructions. Will pick up energy from storage, build new constructions and then repair existing ones. Requires: storage or containers

Will pick up energy from from storage and distribute it to spawns, extensions, towers and upgraders. Requires: storage or containers

Will move resources from containers, tombstones and dropped to storage. Requires: storage and containers

Does nothing. Fallback role used in case of errors.

Will find mine flag without miner creep occupying the position and move to it. Then it will mine adjacent source and drop the energy into a container.

Requires mine flag (containing mine keyword) on a position adjacent to the source. Flag should have saved in memory the source id in source property. A container should be present in the position.

Will look for empty position with upgrade flag and move to it. Then it will upgrade the controller. The role relies on Energy Distributor to be given energy.

Requires: upgrade flag (containing upg keyword) on a position in range of controller upgrading.

Will occupy remote mine flag location, build a container and mine nearby source

Requires flag with remote-mine prefix in range 1 of source

Will transfer energy from remote mine container to storage

Requires: storage and container in remote mine location

Creep spawning mechanism is based on the value of spawn-order parameter defined in spawn memory. The value should be an array of single key-value pair objects, where key is the role name and value is the target creep count.

E.g. [{ harvester: 1 }, { builder: 1 }, { harvester: 3 }]

• if there is no harvesters it will spawn one
• if there is at least one harvester but no builders will spawn a builder
• if there is at least one builder but less then 3 harvesters will spawn a harvester