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Diffstat (limited to 'src/content/en/slide/2020')
| -rw-r--r-- | src/content/en/slide/2020/10/19/feature-flags.adoc | 230 | ||||
| -rw-r--r-- | src/content/en/slide/2020/11/14/local-first-hype.adoc | 204 |
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diff --git a/src/content/en/slide/2020/10/19/feature-flags.adoc b/src/content/en/slide/2020/10/19/feature-flags.adoc new file mode 100644 index 0000000..553cf4c --- /dev/null +++ b/src/content/en/slide/2020/10/19/feature-flags.adoc @@ -0,0 +1,230 @@ +--- +# Rollout, feature flag, experiment, operational toggle + +@Different use cases for backend, frontend and mobile + +--- +. +. +. +# "Feature flags" tend to come up when talking about continuous deployment + +--- +. +. +. +. +@CI: continuous integration +. +@CD: continuous delivery +. +@CD: continuous deployment + +--- +## Types +. +. +. +1. rollout +2. feature flag +3. experiment +4. operational toggle + +% {favicon.svg} +--- +## Rollout + +# For *rolling out* a new version of software + +Short-lived using percentages + +% FIXME: links +- a new deployment of kubernetes +- new APK released to the Play Store + +--- +## Feature flag + +# For turning a feature *on* or *off* + +Medium-lived using allow list, A/B test, percentage, app version, etc. + +- :new-chargeback-flow +- :new-debit-card-activation-screen + +--- +## Experiment + +# For analysing behaviour + +Medium-lived using allow list and A/B test + +- :debit-withdrawal-test + +--- +## Operational toggle + +# For disabling features in #crash-like situations + +Long-lived using percentage + +- :bank-barcode-payment +- :savings-bank-barcode-query-provider + +--- +. +. +@We know know about the types +# But they have different relevance for backend, frontend and mobile + +--- +## backend +. +. +1. rollout: k8s blue/green, canary and ~common-rollout~ common-xp +2. feature flag: ~common-rollout~ common-xp and datasets +3. experiment: common-xp +4. operational toggle: ~common-rollout~ common-xp + +--- +## frontend +. +. +1. rollout: CDN and page refreshes +2. feature flag: percentages and maybe IPs (no :customer/id on the website) +3. experiment: via dynamic backend control +4. operational toggle: via dynamic backend control + +--- +## backend +. +. +1. rollout: app stores +2. feature flag: via dynamic backend control +3. experiment: via dynamic backend control +4. operational toggle: via dynamic backend control + +--- +. +. +@Key differentiator is +# how much *control* we have over the environment + +--- +## backend +# full control +% FIXME: emoji +% 🎉 + +--- +## frontend +# partial control +We choose when to make a new version available + +--- +## mobile +# very limited control +- app stores can restrict updates (worse for iOS) +- customers still have to download new versions + +--- +# Costs +- more complex code +- compatibility with old app versions +- nesting is exponential + +--- +# Benefits +- dynamicity + +--- +## weighting costs × benefits +# The less control we have, the more we value dynamicity + +--- +## weighting costs × benefits +. +. +. +- backend: sometimes worth the cost +- frontend: almost always worth the cost +- mobile: *always* worth the cost + +--- +. +. +. +# Best practices + +--- +# dynamic content > feature flag +Always true for mobile, almost always for frontend + +--- +# Use :include-list for named groups +Always true for backend, frontend and mobile + + {:rules + #{{:types :include-list + :content {:filename "debit-team-members.txt"}}}} + +--- +# Always use :app-version +Only for mobile + + {:rules + #{{:types :app-version + :content {:min-version #{{:platform :android + :code 1000000} + {:platform :ios + :code 2000000}}}}}} + +--- +# Extend ~common-rollout~ common-xp if required + +That's how :include-list, :app-version, etc. were born + +--- +# Beware of many nested feature flags +True for backend, frontend and mobile + +--- +# Don't delete app-facing feature flags +True for mobile + +--- +. +. +. +# Include a feature flag on the whiteboarding phase + +--- +. +. +. +# Include deleting/retiring the feature flag at the end + +--- +# Avoid renaming a feature flag +Use :app-version with :min-version instead + +--- +. +. +. +# And most importantly... + +--- +# *Always* rely on a feature flag on the app +Never do a hotfix, avoid expedited releases at all costs + +--- +## References +. +% FIXME: links +1. "Feature Toggles (aka Feature Flags)", by Pete Hodgson +2. "Continuous integration vs. delivery vs. deployment", by Sten Pittet +3. Accelerate, by N. Forsgren, J. Humble and G. Kim +4. these slides: euandre.org/slide/ +5. prose version of this presentation +6. view source diff --git a/src/content/en/slide/2020/11/14/local-first-hype.adoc b/src/content/en/slide/2020/11/14/local-first-hype.adoc new file mode 100644 index 0000000..fd83115 --- /dev/null +++ b/src/content/en/slide/2020/11/14/local-first-hype.adoc @@ -0,0 +1,204 @@ +# On "local-first" + +@Beyond the CRDT silver bullet + +--- +## Part 1 +# Exposition + +--- +## Target +... +- documents +- files +- personal data repositories +.. +Not: banking services, e-commerce, social networking, ride-sharing, etc. + +--- +... +# 7 ideals for local-first software + +--- +... +# 1 - no spinners: your work at your fingertips + +--- +... +# 2 - your work is not trapped on one device + +--- +... +# 3 - the network is optional + +--- +... +# 4 - seamless collaboration with your colleagues + +--- +... +# 5 - the long now + +--- +... +# 6 - security and privacy by default + +--- +... +# 7 - you retain ultimate ownership and control + +--- +## Towards a better future +.... +@ CRDTs (Conflict-free Replicated Data Types) as a Foundational Technology + +--- +## Use case +. + # in node A and node B + s = "Hello, World" + + # in node A + s = "Hello, Alice" + + # in node B + s = "Hello, Bob" + +How to reconcile those? +- Hello, ABloibce +- Hello, AliceBob +- Hello, BobAlice +- Hello, Alice +\... + +--- +# Existing CRDTs differ +- performance +- storage +- compression +- metadata overhead + +--- +... +# Hint towards the "automerge" CRDT + +--- +...... +@@show comparison table, page 9 + +--- +## Part 2 +# Critique + +--- +## Software license +... +@@"In our opinion, maintaining control and ownership of data does not mean that the software must necessarily be open source." + +--- +## Example 1 - intentional restriction +. + #!/bin/sh + TODAY="$(date +%s)" + LICENSE_EXPIRATION="$(date -d 2020-10-27 +%s)" + if [ "$TODAY" -ge "$LICENSE_EXPIRATION" ]; then + echo 'License expired!' + exit 1 + fi + echo $((2 + 2)) +. + # today + $ ./useful-adder.sh + 4 + + # tomorrow + $ ./useful-adder.sh + License expired! +--- +## Example 2 - unintentional restriction +. + # today + $ useful-program + # ... useful output ... + + # tomorrow, with more data + $ useful-program + ERROR: Panic! Stack overflow! + +--- +.. +# local-first *requires* free software + +Otherwise "The Long Now" (ideal nº5) is lost + +--- +## Denial of existing solutions +.. +@@"In principle it is possible to collaborate without a repository service, e.g. by sending patch files by email, but the majority of Git users rely on GitHub." +. +Solution: either GitHub+CRDTs or git send-email + +--- +## Plain-text formats +. +@@"Git is highly optimized for code and similar line-based text file" +. +It even pulls software to the plain text directtion, e.g.: +- delivery-templates +- common-core.protocols.config +. +Why not exploit that more? + +--- +## Ditching of web applications +.. +@@"The architecture of web apps remains fundamentally server-centric +. +% FIXME: links +Disagree. Contrast PouchDB with Android Instant Apps + +--- +## Costs are underrated +. +- storage +- backups +- maintenance +. +Example: blog vs vlog + +--- +## Real-time collaboration a bit overrated +. +It is only possible on the presence of reliable, medium-quality network connection +.. +@@"X also works when inside an elevator, subway or plane!" + +--- +## On CRDTs and developer experience +. +@@"For an app developer, how does the use of a CRDT-based data layer compare to existing storage layers like a SQL database, a filesystem, or CoreData? Is a distributed system harder to write software for? +. +@YES. +. +% FIXME: link +See "A Note on Distributed Computing" + +--- +## Conclusion +. +Why this is a "paper I love": it took offline-first and ran with it. +. +But a pinch of CRDT won't make the world local-first. +. +The tricky part is the end of the sentence: "in spite of the Cloud". + +--- +## References +. +% FIXME: links +1. "Local-First Software: You Own Your Data, in spite of the Cloud", by M. Kleppmann, A. Wiggins, P. Van Hardenberg and M. F. McGranaghan +2. The Morning Paper article +3. "A Note on Distributed Compiting", by J. Waldo, G. Wyant, A. Wollrath and S. Kendall +4. these slides: euandre.org/slide/ +5. prose version of this presentation +6. view source |