Redowan's Reflections

Archive

2026  26

May  5

If you won't carry the pager, maybe don't push to mainline · article
Testing Go CLIs with testscript · article
A tour of txtar · article
Type-safe slogging · article
Hoisting wire plumbing out of your Go handlers · article

April  6

Go quirks: function closures capturing mutable references · article
Accepted proposal: UUID in the Go standard library · shard
Peeking into Go struct tags · article
Error translation in Go services · article
Dynamo: Amazon's highly available key-value store · paper
Stacked log lines considered harmful · shard

March  12

What's the ideal dispatch mechanism? · shard
Background jobs and inherited file descriptors · shard
Testing unary gRPC services in Go · article
Repositories, transactions, and unit of work in Go · article
How do you handle transactions with the repository pattern? · shard
Is passing user ID through context an antipattern? · shard
What belongs in Go's context values? · shard
Do you need a repository layer on top of sqlc? · shard
Wrapping a gRPC client in Go · article
In praise of the etcd codebase · shard
Go errors: to wrap or not to wrap? · article
Mutate your locked state inside a closure · article

February  2

What canceled my Go context? · article
Structured concurrency & Go · article

January  1

Your Go tests probably don't need a mocking library · article

2025  27

December  1

Tap compare testing for service migration · article

November  3

Splintered failure modes in Go · article
Re-exec testing Go subprocesses · article
Revisiting interface segregation in Go · article

October  3

Avoiding collisions in Go context keys · article
Organizing Go tests · article
Subtest grouping in Go · article

September  3

Let the domain guide your application structure · article
Test state, not interactions · article
Early return and goroutine leak · article

August  2

Lifecycle management in Go tests · article
Gateway pattern for external service calls · article

June  1

Flags for discoverable test config in Go · article

May  1

You probably don't need a DI framework · article

April  3

Preventing accidental struct copies in Go · article
Go 1.24's "tool" directive · article
Capturing console output in Go tests · article

March  4

Deferred teardown closure in Go testing · article
Three flavors of sorting Go slices · article
Nil comparisons and Go interface · article
Stacked middleware vs embedded delegation in Go · article

February  2

Why does Go's io.Reader have such a weird signature? · article
Go slice gotchas · article

January  4

The domain knowledge dilemma · article
Hierarchical rate limiting with Redis sorted sets · article
Dynamic shell variables · article
Link blog in a static site · article

2024  40

December  4

Running only a single instance of a process · article
Function types and single-method interfaces in Go · article
SSH saga · article
Injecting Pytest fixtures without cluttering test signatures · article

November  2

Explicit method overriding with @typing.override · article
Quicker startup with module-level __getattr__ · article

October  4

Docker mount revisited · article
Topological sort · article
Writing a circuit breaker in Go · article
Discovering direnv · article

September  5

Notes on building event-driven systems · article
Bash namerefs for dynamic variable referencing · article
Behind the blog · article
Shell redirection syntax soup · article
Shades of testing HTTP requests in Python · article

August  4

Taming parametrize with pytest.param · article
HTTP requests via /dev/tcp · article
Log context propagation in Python ASGI apps · article
Please don't hijack my Python root logger · article

July  3

The *nix install command · article
Here-doc headache · article
The sane pull request · article

June  1

I kind of like rebasing · article

May  1

Protobuffed contracts · article

April  2

TypeIs does what I thought TypeGuard would do in Python · article
ETag and HTTP caching · article

March  2

Crossing the CORS crossroad · article
Dysfunctional options pattern in Go · article

February  4

Einstellung effect · article
Strategy pattern in Go · article
Anemic stack traces in Go · article
Retry function in Go · article

January  8

Type assertion vs type switches in Go · article
Patching pydantic settings in pytest · article
Omitting dev dependencies in Go binaries · article
Eschewing black box API calls · article
Annotating args and kwargs in Python · article
Rate limiting via Nginx · article
Statically enforcing frozen data classes in Python · article
Planning palooza · article

2023  48

December  3

Reminiscing CGI scripts · article
Debugging dockerized Python apps in VSCode · article
Banish state-mutating methods from data classes · article

November  3

Finding flow amid chaos · article
The diminishing half-life of knowledge · article
Oh my poor business logic · article

October  2

Pesky little scripts · article
Footnotes for the win · article

September  4

Dotfile stewardship for the indolent · article
An ode to the neo-grotesque web · article
Self-hosted Google Fonts in Hugo · article
Configuring options in Go · article

August  7

Dummy load balancer in a single Go script · article
Limit goroutines with buffered channels · article
Writing a TOTP client in Go · article
Interface guards in Go · article
Writing on well-trodden topics · article
Go structured logging with slog · article
Notes on exit interviews · article

July  7

Taming conditionals with bitmasks · article
Using DNS record to share text data · article
Memory leakage in Python descriptors · article
Unix-style pipelining with Python's subprocess module · article
Enabling repeatable lazy iterations in Python · article
Descending into the aether · article
Escaping the template pattern hellscape in Python · article

June  2

Python dependency management redux · article
Implementing a simple traceroute clone in Python · article

May  7

Bulk request Google search indexing with API · article
Building a CORS proxy with Cloudflare Workers · article
Fixed-time job scheduling with UNIX 'at' command · article
Sorting a Django queryset by a custom sequence of an attribute · article
Periodic readme updates with GitHub Actions · article
Associative arrays in Bash · article
Deduplicating iterables while preserving order in Python · article

April  5

Process substitution in Bash · article
Dynamic menu with select statement in Bash · article
Simple terminal text formatting with tput · article
Building a web app to display CSV file stats with ChatGPT & Observable · article
Pushing real-time updates to clients with Server-Sent Events (SSEs) · article

March  1

Tinkering with Unix domain sockets · article

February  4

Signal handling in a multithreaded socket server · article
Switching between multiple data streams in a single thread · article
Skipping the first part of an iterable in Python · article
Pausing and resuming a socket server in Python · article

January  3

Debugging a containerized Django application in Jupyter Notebook · article
Manipulating text with query expressions in Django · article
Using tqdm with concurrent.fututes in Python · article

2022  61

December  1

Colon command in shell scripts · article

November  3

Faster bulk_update in Django · article
Installing Python on macOS with asdf · article
Save models with update_fields for better performance in Django · article

October  4

Python logging quirks in AWS Lambda environment · article
Dissecting an outage caused by eager-loading file content · article
Auditing commit messages on GitHub · article
To quote or not to quote · article

September  5

Returning values from a shell function · article
Verifying webhook origin via payload hash signing · article
Recipes from Python SQLite docs · article
Prefer urlsplit over urlparse to destructure URLs · article
Pick random values from an array in SQL(ite) · article

August  1

ExitStack in Python · article

July  7

Compose multiple levels of fixtures in pytest · article
Patch where the object is used · article
Partially assert callable arguments with 'unittest.mock.ANY' · article
When to use 'git pull --rebase' · article
Apply constraints with 'assert' in Python · article
Automerge Dependabot PRs on GitHub · article
Stream process a CSV file in Python · article

June  4

Bulk operations in Django with process pool · article
Read a CSV file from s3 without saving it to the disk · article
Distil git logs attached to a single file · article
Safer 'operator.itemgetter' in Python · article

May  1

Guard clause and exhaustiveness checking · article

April  3

Health check a server with 'nohup $(cmd) &' · article
Return JSON error payload instead of HTML text in DRF · article
Decoupling producers and consumers of iterables with generators in Python · article

March  11

Pre-allocated lists in Python · article
In favor of sentence case · article
Disallow large file download from URLs in Python · article
Declaratively transform data class fields in Python · article
Caching connection objects in Python · article
How not to run a script in Python · article
Mocking chained methods of datetime objects in Python · article
Declarative payloads with TypedDict in Python · article
Parametrized fixtures in pytest · article
Modify iterables while iterating in Python · article
Github action template for Python based projects · article

February  9

Self type in Python · article
Patching test dependencies via pytest fixture & unittest mock · article
Narrowing types with TypeGuard in Python · article
Why 'NoReturn' type exists in Python · article
Add extra attributes to enum members in Python · article
Peeking into the internals of Python's 'functools.wraps' decorator · article
Limit concurrency with semaphore in Python asyncio · article
Amphibian decorators in Python · article
Go Rusty with exception handling in Python · article

January  12

Variance of generic types in Python · article
Create a sub dictionary with O(K) complexity in Python · article
Gotchas of early-bound function argument defaults in Python · article
Use 'assertIs' to check literal booleans in Python unittest · article
Static typing Python decorators · article
Inspect docstrings with Pydoc · article
Check whether an integer is a power of two in Python · article
Uniform error response in Django Rest Framework · article
Difference between constrained 'TypeVar' and 'Union' in Python · article
Don't wrap instance methods with 'functools.lru_cache' decorator in Python · article
Cropping texts in Python with 'textwrap.shorten' · article
String interning in Python · article

2021  12

December  1

Structural subtyping in Python · article

November  11

Automatic attribute delegation in Python composition · article
Access 'classmethod's like 'property' methods in Python · article
Don't add extensions to shell executables · article
Use __init_subclass__ hook to validate subclasses in Python · article
Running tqdm with Python multiprocessing · article
Use daemon threads to test infinite while loops in Python · article
Use 'command -v' over 'which' to find a program's executable · article
Write git commit messages properly · article
Python's 'functools.partial' flattens nestings Automatically · article
Use curly braces while pasting shell commands · article
Use strict mode while running bash scripts · article

2020  12

July  2

Pedantic configuration management with Pydantic · article
Interfaces, mixins and building powerful custom data structures in Python · article

June  2

Deciphering Python's metaclasses · article
Implementing proxy pattern in Python · article

May  2

Effortless API response caching with Python & Redis · article
Untangling Python decorators · article

April  4

Effortless concurrency with Python's concurrent.futures · article
No really, Python's pathlib is great · article
Running Python linters with pre-commit hooks · article
Generic functions with Python's singledispatch · article

March  2

The curious case of Python's context manager · article
Reduce boilerplate code with Python's dataclasses · article