ElixirDrops

Welcome to ElixirDrops!

Hello there and welcome to the ultimate hub for the Elixir community! Whether you're a seasoned developer or just starting your journey, ElixirDrops is the perfect place to discover, share, and discuss the best tips and tricks for mastering Elixir. Sign in to explore, learn and become a contributor on this platform.

Admit when you’re wrong

People in the Elixir community shouldn't be butthurt about DHH's Campfire benchmarks. We should use them as an opportunity to look at the state of the...

almirsarajcic

8 hours ago

Trapping exits so terminate/2 actually runs

A GenServer that flushes buffered work in terminate/2 loses it when its supervisor shuts it down, unless the process traps exits:...

almirsarajcic

7 days ago

Keeping compile_env values out of runtime.exs

Application.compile_env/3 bakes a value into the module when it compiles. If config/runtime.exs sets the same key, the two can disagree without anyone...

almirsarajcic

11 days ago

Sorting DateTime lists with Enum.sort/2

Enum.sort/1 puts January 31 after February 1:...

almirsarajcic

12 days ago

Setting updated_at yourself in Repo.update_all/3

Repo.update_all/3 writes the columns you give it and nothing else, so updated_at keeps its old value:...

almirsarajcic

13 days ago

How we use ETS as a live code-graph database in Synapse MCP

We have built/building Synapse MCP — a tool that gives AI agents a persistent map of your codebase — and one design question came up early: where does...

spasm-myelixlabs

13 days ago

Running doctests against the database

Doctests are straightforward until an example calls Repo. A plain ExUnit case doesn't check out an Ecto sandbox connection, so run database-backed doc...

almirsarajcic

14 days ago

Keeping Oban's time units explicit

Oban's Lifeline and Pruner accept raw integers in different units: rescue_after is milliseconds, while max_age is seconds. On current Oban releases, ...

almirsarajcic

15 days ago

Catching GenServer.call/3 timeout exits

GenServer.call/3 does not return {:error, :timeout} when the server misses its deadline. It exits the caller instead....

almirsarajcic

16 days ago

Keeping self() straight in on_exit callbacks

An on_exit callback looks like it belongs to the test that registered it, but self() inside the callback is not the test PID:...

almirsarajcic

17 days ago

Clearing inherited variables in System.cmd

Passing env: [] to System.cmd/3 does not clear the child environment....

almirsarajcic

18 days ago

Running Task.async_stream/3 for side effects

Calling Task.async_stream/3 does not start any tasks:...

almirsarajcic

19 days ago

Keeping timeouts active while tracing tests

A test can stop timing out when you rerun it with --trace:...

almirsarajcic

20 days ago

Starting only what a FLAME runner needs

When FLAME boots a remote runner, it starts your application there, so your application has to decide which supervision children belong on that runner...

almirsarajcic

21 days ago

Keeping stale gzip assets out of Phoenix tests

I spent too long debugging a LiveView hook in ElixirDrops because the browser kept running old JavaScript. The source and freshly built app.js were co...

almirsarajcic

22 days ago